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Question 1
Correct
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A 45 year old male is brought into the emergency department by a family member with a 2 day history of nausea and vomiting. On initial assessment the patient appears disoriented. Observations reveal the patient to have a heart rate of 140 beats per minute and blood pressure of 90/60 mmHg. You contemplate the possibility of Addison's disease. What is the primary cause of Addison's disease in the United Kingdom?
Your Answer: Autoimmune adrenalitis
Explanation:Addison’s disease is primarily caused by tuberculosis, making it the most prevalent factor worldwide.
Further Reading:
Addison’s disease, also known as primary adrenal insufficiency or hypoadrenalism, is a rare disorder caused by the destruction of the adrenal cortex. This leads to reduced production of glucocorticoids, mineralocorticoids, and adrenal androgens. The deficiency of cortisol results in increased production of adrenocorticotropic hormone (ACTH) due to reduced negative feedback to the pituitary gland. This condition can cause metabolic disturbances such as hyperkalemia, hyponatremia, hypercalcemia, and hypoglycemia.
The symptoms of Addison’s disease can vary but commonly include fatigue, weight loss, muscle weakness, and low blood pressure. It is more common in women and typically affects individuals between the ages of 30-50. The most common cause of primary hypoadrenalism in developed countries is autoimmune destruction of the adrenal glands. Other causes include tuberculosis, adrenal metastases, meningococcal septicaemia, HIV, and genetic disorders.
The diagnosis of Addison’s disease is often suspected based on low cortisol levels and electrolyte abnormalities. The adrenocorticotropic hormone stimulation test is commonly used for confirmation. Other investigations may include adrenal autoantibodies, imaging scans, and genetic screening.
Addisonian crisis is a potentially life-threatening condition that occurs when there is an acute deficiency of cortisol and aldosterone. It can be the first presentation of undiagnosed Addison’s disease. Precipitating factors of an Addisonian crisis include infection, dehydration, surgery, trauma, physiological stress, pregnancy, hypoglycemia, and acute withdrawal of long-term steroids. Symptoms of an Addisonian crisis include malaise, fatigue, nausea or vomiting, abdominal pain, fever, muscle pains, dehydration, confusion, and loss of consciousness.
There is no fixed consensus on diagnostic criteria for an Addisonian crisis, as symptoms are non-specific. Investigations may include blood tests, blood gas analysis, and septic screens if infection is suspected. Management involves administering hydrocortisone and fluids. Hydrocortisone is given parenterally, and the dosage varies depending on the age of the patient. Fluid resuscitation with saline is necessary to correct any electrolyte disturbances and maintain blood pressure. The underlying cause of the crisis should also be identified and treated. Close monitoring of sodium levels is important to prevent complications such as osmotic demyelination syndrome.
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This question is part of the following fields:
- Endocrinology
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Question 2
Correct
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You are managing a 32-year-old type 1 diabetic patient who presented feeling generally unwell with a blood glucose of 27 mmol/l. The patient is currently being treated for diabetic ketoacidosis. The patient weighs 70kg and is currently receiving the following:
0.9% sodium chloride 1L with 40 mmol/l potassium chloride over 4 hours
3 units Actrapid® insulin / hour.
Monitoring bloods are taken and the results are shown below:
glucose 12.8 mmol/l
potassium 3.7 mmol/l
sodium 145 mmol/l
pH 7.2
What is the most appropriate action to take for this patient?Your Answer: Start 10% glucose infusion at a rate of 125 mL/hour in addition to existing treatment
Explanation:The healthcare provider should also assess the insulin infusion rate. It is important to note that the recommended minimum rate is 0.05 units per kilogram per hour. In this case, the patient weighs 60 kilograms and is currently receiving 3 units of Actrapid® insulin per hour, which is equivalent to 0.05 units per kilogram per hour. Therefore, the patient is already on the lowest possible dose. However, if the patient was on a higher dose of 0.1 units per kilogram per hour, it can be reduced once the glucose level falls below 14 mmol/l.
Further Reading:
Diabetic ketoacidosis (DKA) is a serious complication of diabetes that occurs due to a lack of insulin in the body. It is most commonly seen in individuals with type 1 diabetes but can also occur in type 2 diabetes. DKA is characterized by hyperglycemia, acidosis, and ketonaemia.
The pathophysiology of DKA involves insulin deficiency, which leads to increased glucose production and decreased glucose uptake by cells. This results in hyperglycemia and osmotic diuresis, leading to dehydration. Insulin deficiency also leads to increased lipolysis and the production of ketone bodies, which are acidic. The body attempts to buffer the pH change through metabolic and respiratory compensation, resulting in metabolic acidosis.
DKA can be precipitated by factors such as infection, physiological stress, non-compliance with insulin therapy, acute medical conditions, and certain medications. The clinical features of DKA include polydipsia, polyuria, signs of dehydration, ketotic breath smell, tachypnea, confusion, headache, nausea, vomiting, lethargy, and abdominal pain.
The diagnosis of DKA is based on the presence of ketonaemia or ketonuria, blood glucose levels above 11 mmol/L or known diabetes mellitus, and a blood pH below 7.3 or bicarbonate levels below 15 mmol/L. Initial investigations include blood gas analysis, urine dipstick for glucose and ketones, blood glucose measurement, and electrolyte levels.
Management of DKA involves fluid replacement, electrolyte correction, insulin therapy, and treatment of any underlying cause. Fluid replacement is typically done with isotonic saline, and potassium may need to be added depending on the patient’s levels. Insulin therapy is initiated with an intravenous infusion, and the rate is adjusted based on blood glucose levels. Monitoring of blood glucose, ketones, bicarbonate, and electrolytes is essential, and the insulin infusion is discontinued once ketones are below 0.3 mmol/L, pH is above 7.3, and bicarbonate is above 18 mmol/L.
Complications of DKA and its treatment include gastric stasis, thromboembolism, electrolyte disturbances, cerebral edema, hypoglycemia, acute respiratory distress syndrome, and acute kidney injury. Prompt medical intervention is crucial in managing DKA to prevent potentially fatal outcomes.
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This question is part of the following fields:
- Endocrinology
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Question 3
Correct
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A patient arrives at the emergency department with confusion and abdominal pain. They have a previous diagnosis of Addison's disease but have recently run out of their steroid medication. You suspect the patient is experiencing an Addisonian crisis.
Which ONE clinical feature is NOT typically associated with an Addisonian crisis?Your Answer: Hyperglycaemia
Explanation:An Addisonian crisis is characterized by several distinct features. These include experiencing pain in the legs and abdomen, as well as symptoms of vomiting and dehydration. Hypotension, or low blood pressure, is also commonly observed during an Addisonian crisis. Confusion and psychosis may also occur, along with the presence of a fever. In some cases, convulsions may be present as well. Additionally, individuals experiencing an Addisonian crisis may also exhibit hypoglycemia, hyponatremia, hyperkalemia, hypercalcemia, eosinophilia, and metabolic acidosis.
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This question is part of the following fields:
- Endocrinology
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Question 4
Incorrect
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A 32 year old male attends the emergency department following a fall in which he sustained a minor head injury. You observe that the patient is a Ukrainian refugee and has recently arrived in the UK. During the assessment, you notice a significant goitre. Upon checking his thyroid function, it confirms hypothyroidism. What is the most probable reason for his hypothyroidism?
Your Answer: Hashimoto's thyroiditis
Correct Answer: Iodine deficiency
Explanation:Iodine deficiency is a widespread issue globally and is the leading cause of hypothyroidism worldwide. It is particularly prevalent in numerous African countries, as well as in developed nations such as Norway, Germany, Russia, and Ukraine. In the UK, however, autoimmune thyroiditis is the most common cause of hypothyroidism.
Further Reading:
The thyroid gland is an endocrine organ located in the anterior neck. It consists of two lobes connected by an isthmus. The gland produces hormones called thyroxine (T4) and triiodothyronine (T3), which regulate energy use, protein synthesis, and the body’s sensitivity to other hormones. The production of T4 and T3 is stimulated by thyroid-stimulating hormone (TSH) secreted by the pituitary gland, which is in turn stimulated by thyrotropin-releasing hormone (TRH) from the hypothalamus.
Thyroid disorders can occur when there is an imbalance in the production or regulation of thyroid hormones. Hypothyroidism is characterized by a deficiency of thyroid hormones, while hyperthyroidism is characterized by an excess. The most common cause of hypothyroidism is autoimmune thyroiditis, also known as Hashimoto’s thyroiditis. It is more common in women and is often associated with goiter. Other causes include subacute thyroiditis, atrophic thyroiditis, and iodine deficiency. On the other hand, the most common cause of hyperthyroidism is Graves’ disease, which is also an autoimmune disorder. Other causes include toxic multinodular goiter and subacute thyroiditis.
The symptoms and signs of thyroid disorders can vary depending on whether the thyroid gland is underactive or overactive. In hypothyroidism, common symptoms include weight gain, lethargy, cold intolerance, and dry skin. In hyperthyroidism, common symptoms include weight loss, restlessness, heat intolerance, and increased sweating. Both hypothyroidism and hyperthyroidism can also affect other systems in the body, such as the cardiovascular, gastrointestinal, and neurological systems.
Complications of thyroid disorders can include dyslipidemia, metabolic syndrome, coronary heart disease, heart failure, subfertility and infertility, impaired special senses, and myxedema coma in severe cases of hypothyroidism. In hyperthyroidism, complications can include Graves’ orbitopathy, compression of the esophagus or trachea by goiter, thyrotoxic periodic paralysis, arrhythmias, osteoporosis, mood disorders, and increased obstetric complications.
Myxedema coma is a rare and life-threatening complication of severe hypothyroidism. It can be triggered by factors such as infection or physiological insult and presents with lethargy, bradycardia, hypothermia, hypotension, hypoventilation, altered mental state, seizures and/or coma.
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This question is part of the following fields:
- Endocrinology
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Question 5
Correct
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A 42 year old male patient is brought into resus with a three day history of nausea and vomiting. He has decreased GCS, is hypotensive and tachycardic. His roommate informs you that he was diagnosed with Addison's disease approximately six months ago and frequently neglects to take his prescribed medication. What is the most accurate description of the underlying cause of Addison's disease?
Your Answer: Destruction of the adrenal cortex
Explanation:Addison’s disease occurs when the adrenal cortex is destroyed. The anterior pituitary gland produces and releases adrenocorticotropic hormone (ACTH), not the posterior pituitary gland. The adrenal cortex is responsible for producing cortisol, not the adrenal medulla.
Further Reading:
Addison’s disease, also known as primary adrenal insufficiency or hypoadrenalism, is a rare disorder caused by the destruction of the adrenal cortex. This leads to reduced production of glucocorticoids, mineralocorticoids, and adrenal androgens. The deficiency of cortisol results in increased production of adrenocorticotropic hormone (ACTH) due to reduced negative feedback to the pituitary gland. This condition can cause metabolic disturbances such as hyperkalemia, hyponatremia, hypercalcemia, and hypoglycemia.
The symptoms of Addison’s disease can vary but commonly include fatigue, weight loss, muscle weakness, and low blood pressure. It is more common in women and typically affects individuals between the ages of 30-50. The most common cause of primary hypoadrenalism in developed countries is autoimmune destruction of the adrenal glands. Other causes include tuberculosis, adrenal metastases, meningococcal septicaemia, HIV, and genetic disorders.
The diagnosis of Addison’s disease is often suspected based on low cortisol levels and electrolyte abnormalities. The adrenocorticotropic hormone stimulation test is commonly used for confirmation. Other investigations may include adrenal autoantibodies, imaging scans, and genetic screening.
Addisonian crisis is a potentially life-threatening condition that occurs when there is an acute deficiency of cortisol and aldosterone. It can be the first presentation of undiagnosed Addison’s disease. Precipitating factors of an Addisonian crisis include infection, dehydration, surgery, trauma, physiological stress, pregnancy, hypoglycemia, and acute withdrawal of long-term steroids. Symptoms of an Addisonian crisis include malaise, fatigue, nausea or vomiting, abdominal pain, fever, muscle pains, dehydration, confusion, and loss of consciousness.
There is no fixed consensus on diagnostic criteria for an Addisonian crisis, as symptoms are non-specific. Investigations may include blood tests, blood gas analysis, and septic screens if infection is suspected. Management involves administering hydrocortisone and fluids. Hydrocortisone is given parenterally, and the dosage varies depending on the age of the patient. Fluid resuscitation with saline is necessary to correct any electrolyte disturbances and maintain blood pressure. The underlying cause of the crisis should also be identified and treated. Close monitoring of sodium levels is important to prevent complications such as osmotic demyelination syndrome.
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This question is part of the following fields:
- Endocrinology
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Question 6
Correct
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A 45-year-old man with a long-standing history of type 2 diabetes mellitus complains of pain in his left buttock, hip, and thigh. The pain began abruptly a couple of months ago, and he cannot recall any previous injury. During the examination, you observe muscle wasting in his left quadriceps, struggles in standing up from a seated position, and an absent knee jerk on the left side. Additionally, you notice muscle fasciculations in his left thigh.
What is the SINGLE most probable diagnosis?Your Answer: Diabetic amyotrophy
Explanation:Diabetic amyotrophy, also referred to as proximal diabetic neuropathy, is the second most prevalent form of diabetic neuropathy. It typically begins with discomfort in the buttocks, hips, or thighs and is often initially experienced on one side. The pain may start off as mild and gradually progress or it can suddenly manifest, as seen in this case. Subsequently, weakness and wasting of the proximal muscles in the lower limbs occur, making it difficult for the patient to transition from sitting to standing without assistance. Reflexes in the affected areas can also be impacted. Good control of blood sugar levels, physiotherapy, and lifestyle adjustments can reverse diabetic amyotrophy.
Peripheral neuropathy is the most common type of diabetic neuropathy and typically manifests as pain or loss of sensation in the feet or hands.
Autonomic neuropathy leads to changes in digestion, bowel and bladder function, sexual response, and perspiration. It can also affect the cardiovascular system, resulting in rapid heart rates and orthostatic hypotension.
Focal neuropathy causes sudden weakness in a single nerve or group of nerves, resulting in pain, sensory loss, or muscle weakness. Any nerve in the body can be affected.
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This question is part of the following fields:
- Endocrinology
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Question 7
Correct
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A 62 year old male presents to the emergency department with complaints of fatigue, headache, and muscle spasms. Upon examination, the patient is found to have hypertension with a blood pressure reading of 198/96 mmHg. In order to screen for secondary causes of hypertension, which of the following tests would be the most suitable for detecting Conn's syndrome?
Your Answer: Aldosterone and renin levels
Explanation:The preferred diagnostic test for hyperaldosteronism is the plasma aldosterone-to-renin ratio (ARR). Hyperaldosteronism is also known as Conn’s syndrome and can be diagnosed by measuring aldosterone and renin levels. By calculating the aldosterone-to-renin ratio, an abnormal increase (>30 ng/dL per ng/mL/h) can indicate primary hyperaldosteronism. Adrenal insufficiency can be detected using the Synacthen test. To detect phaeochromocytoma, tests such as plasma metanephrines and urine vanillylmandelic acid are used. The dexamethasone suppression test is employed for diagnosing Cushing syndrome.
Further Reading:
Hyperaldosteronism is a condition characterized by excessive production of aldosterone by the adrenal glands. It can be classified into primary and secondary hyperaldosteronism. Primary hyperaldosteronism, also known as Conn’s syndrome, is typically caused by adrenal hyperplasia or adrenal tumors. Secondary hyperaldosteronism, on the other hand, is a result of high renin levels in response to reduced blood flow across the juxtaglomerular apparatus.
Aldosterone is the main mineralocorticoid steroid hormone produced by the adrenal cortex. It acts on the distal renal tubule and collecting duct of the nephron, promoting the reabsorption of sodium ions and water while secreting potassium ions.
The causes of hyperaldosteronism vary depending on whether it is primary or secondary. Primary hyperaldosteronism can be caused by adrenal adenoma, adrenal hyperplasia, adrenal carcinoma, or familial hyperaldosteronism. Secondary hyperaldosteronism can be caused by renal artery stenosis, reninoma, renal tubular acidosis, nutcracker syndrome, ectopic tumors, massive ascites, left ventricular failure, or cor pulmonale.
Clinical features of hyperaldosteronism include hypertension, hypokalemia, metabolic alkalosis, hypernatremia, polyuria, polydipsia, headaches, lethargy, muscle weakness and spasms, and numbness. It is estimated that hyperaldosteronism is present in 5-10% of patients with hypertension, and hypertension in primary hyperaldosteronism is often resistant to drug treatment.
Diagnosis of hyperaldosteronism involves various investigations, including U&Es to assess electrolyte disturbances, aldosterone-to-renin plasma ratio (ARR) as the gold standard diagnostic test, ECG to detect arrhythmia, CT/MRI scans to locate adenoma, fludrocortisone suppression test or oral salt testing to confirm primary hyperaldosteronism, genetic testing to identify familial hyperaldosteronism, and adrenal venous sampling to determine lateralization prior to surgery.
Treatment of primary hyperaldosteronism typically involves surgical adrenalectomy for patients with unilateral primary aldosteronism. Diet modification with sodium restriction and potassium supplementation may also be recommended.
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This question is part of the following fields:
- Endocrinology
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Question 8
Correct
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A 68-year-old diabetic man presents with a gradual decrease in consciousness and confusion over the past week. He normally controls his diabetes with metformin 500 mg twice a day. He recently received treatment for a urinary tract infection from his doctor, and his family reports that he has been excessively thirsty. He has vomited multiple times today. A urine dipstick test shows a small amount of white blood cells and moderate ketones. The results of his arterial blood gas test are as follows:
pH: 7.29
pO2: 11.1 kPa
pCO2: 4.6 kPa
HCO3-: 22 mmol/l
Na+: 154 mmol/l
K+: 3.2 mmol/l
Cl-: 100 mmol/l
Urea: 17.6 mmol/l
Glucose: 32 mmol/l
What is his serum osmolality?Your Answer: 364 mmol/l
Explanation:In an elderly patient with a history of gradual decline accompanied by high blood sugar levels, excessive thirst, and recent infection, the most likely diagnosis is hyperosmolar hyperglycemic state (HHS). This condition can be life-threatening, with a mortality rate of approximately 50%. Common symptoms include dehydration, elevated blood sugar levels, altered mental status, and electrolyte imbalances. About half of the patients with HHS also experience hypernatremia.
To calculate the serum osmolality, the formula is 2(K+ + Na+) + urea + glucose. In this case, the serum osmolality is 364 mmol/l, indicating a high level. It is important to discontinue the use of metformin in this patient due to the risk of metformin-associated lactic acidosis (MALA). Additionally, an intravenous infusion of insulin should be initiated.
The treatment goals for HHS are to address the underlying cause and gradually and safely:
– Normalize the osmolality
– Replace fluid and electrolyte losses
– Normalize blood glucose levelsIf significant ketonaemia is present (3β-hydroxybutyrate is more than 1 mmol/L), it indicates a relative lack of insulin, and insulin should be administered immediately. However, if significant ketonaemia is not present, insulin should not be started.
Patients with HHS are at a high risk of thromboembolism, and it is recommended to routinely administer low molecular weight heparin. In cases where the serum osmolality exceeds 350 mmol/l, full heparinization should be considered.
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This question is part of the following fields:
- Endocrinology
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Question 9
Incorrect
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A 75 year old man with a long-standing history of hypothyroidism presents to the emergency department due to worsening confusion and fatigue. On examination you note diffuse non-pitting edema and decreased deep tendon reflexes. Observations are shown below:
Blood pressure 98/66 mmHg
Pulse 42 bpm
Respiration rate 11 bpm
Temperature 34.6ºC
Bloods are sent for analysis. Which of the following laboratory abnormalities would you expect in a patient with this condition?Your Answer: Low TSH
Correct Answer: Hyponatremia
Explanation:Myxoedema coma is a condition characterized by severe hypothyroidism, leading to a state of metabolic decompensation and changes in mental status. Patients with myxoedema coma often experience electrolyte disturbances such as hypoglycemia and hyponatremia. In addition, laboratory findings typically show elevated levels of TSH, as well as low levels of T4 and T3. Other expected findings include hypoxemia and hypercapnia.
Further Reading:
The thyroid gland is an endocrine organ located in the anterior neck. It consists of two lobes connected by an isthmus. The gland produces hormones called thyroxine (T4) and triiodothyronine (T3), which regulate energy use, protein synthesis, and the body’s sensitivity to other hormones. The production of T4 and T3 is stimulated by thyroid-stimulating hormone (TSH) secreted by the pituitary gland, which is in turn stimulated by thyrotropin-releasing hormone (TRH) from the hypothalamus.
Thyroid disorders can occur when there is an imbalance in the production or regulation of thyroid hormones. Hypothyroidism is characterized by a deficiency of thyroid hormones, while hyperthyroidism is characterized by an excess. The most common cause of hypothyroidism is autoimmune thyroiditis, also known as Hashimoto’s thyroiditis. It is more common in women and is often associated with goiter. Other causes include subacute thyroiditis, atrophic thyroiditis, and iodine deficiency. On the other hand, the most common cause of hyperthyroidism is Graves’ disease, which is also an autoimmune disorder. Other causes include toxic multinodular goiter and subacute thyroiditis.
The symptoms and signs of thyroid disorders can vary depending on whether the thyroid gland is underactive or overactive. In hypothyroidism, common symptoms include weight gain, lethargy, cold intolerance, and dry skin. In hyperthyroidism, common symptoms include weight loss, restlessness, heat intolerance, and increased sweating. Both hypothyroidism and hyperthyroidism can also affect other systems in the body, such as the cardiovascular, gastrointestinal, and neurological systems.
Complications of thyroid disorders can include dyslipidemia, metabolic syndrome, coronary heart disease, heart failure, subfertility and infertility, impaired special senses, and myxedema coma in severe cases of hypothyroidism. In hyperthyroidism, complications can include Graves’ orbitopathy, compression of the esophagus or trachea by goiter, thyrotoxic periodic paralysis, arrhythmias, osteoporosis, mood disorders, and increased obstetric complications.
Myxedema coma is a rare and life-threatening complication of severe hypothyroidism. It can be triggered by factors such as infection or physiological insult and presents with lethargy, bradycardia, hypothermia, hypotension, hypoventilation, altered mental state, seizures and/or coma.
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This question is part of the following fields:
- Endocrinology
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Question 10
Incorrect
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A 7 year old girl is brought into the emergency department with a 24 hour history of vomiting and becoming increasingly tired. A capillary blood glucose is taken and the result is shown as 25 mmol/l. You suspect diabetic ketoacidosis (DKA). Which of the following is included in the diagnostic criteria for DKA?
Your Answer: Blood pH <7.3 or bicarbonate <15 mmol/L
Correct Answer:
Explanation:To diagnose diabetic ketoacidosis (DKA), all three of the following criteria must be present: ketonaemia (≥3 mmol/L) or ketonuria (> 2+ on urine dipstick), blood glucose > 11 mmol/L or known diabetes mellitus, and blood pH <7.3 or bicarbonate < 15 mmol/L. It is important to note that plasma osmolality and anion gap, although typically elevated in DKA, are not included in the diagnostic criteria. Further Reading: Diabetic ketoacidosis (DKA) is a serious complication of diabetes that occurs due to a lack of insulin in the body. It is most commonly seen in individuals with type 1 diabetes but can also occur in type 2 diabetes. DKA is characterized by hyperglycemia, acidosis, and ketonaemia. The pathophysiology of DKA involves insulin deficiency, which leads to increased glucose production and decreased glucose uptake by cells. This results in hyperglycemia and osmotic diuresis, leading to dehydration. Insulin deficiency also leads to increased lipolysis and the production of ketone bodies, which are acidic. The body attempts to buffer the pH change through metabolic and respiratory compensation, resulting in metabolic acidosis. DKA can be precipitated by factors such as infection, physiological stress, non-compliance with insulin therapy, acute medical conditions, and certain medications. The clinical features of DKA include polydipsia, polyuria, signs of dehydration, ketotic breath smell, tachypnea, confusion, headache, nausea, vomiting, lethargy, and abdominal pain. The diagnosis of DKA is based on the presence of ketonaemia or ketonuria, blood glucose levels above 11 mmol/L or known diabetes mellitus, and a blood pH below 7.3 or bicarbonate levels below 15 mmol/L. Initial investigations include blood gas analysis, urine dipstick for glucose and ketones, blood glucose measurement, and electrolyte levels. Management of DKA involves fluid replacement, electrolyte correction, insulin therapy, and treatment of any underlying cause. Fluid replacement is typically done with isotonic saline, and potassium may need to be added depending on the patient’s levels. Insulin therapy is initiated with an intravenous infusion, and the rate is adjusted based on blood glucose levels. Monitoring of blood glucose, ketones, bicarbonate, and electrolytes is essential, and the insulin infusion is discontinued once ketones are below 0.3 mmol/L, pH is above 7.3, and bicarbonate is above 18 mmol/L. Complications of DKA and its treatment include gastric stasis, thromboembolism, electrolyte disturbances, cerebral edema, hypoglycemia, acute respiratory distress syndrome, and acute kidney injury. Prompt medical intervention is crucial in managing DKA to prevent potentially fatal outcomes.
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This question is part of the following fields:
- Endocrinology
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Question 11
Correct
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A 20-year-old woman presents with frequent urination, excessive thirst, and stomach pain. The results of her arterial blood gas (ABG) on air are as follows:
pH: 7.21
pO2: 11.4 kPa
PCO2: 3.1 kPa
HCO3-: 17 mmol/l
Na+: 149 mmol/l
Cl–: 100 mmol/l
Lactate: 6 IU/l
Which SINGLE statement about this patient is correct?Your Answer: She is likely to have a type B lactic acidosis
Explanation:Arterial blood gas (ABG) interpretation is essential for evaluating a patient’s respiratory gas exchange and acid-base balance. While the normal values on an ABG may slightly vary between analyzers, they generally fall within the following ranges:
pH: 7.35 – 7.45
pO2: 10 – 14 kPa
PCO2: 4.5 – 6 kPa
HCO3-: 22 – 26 mmol/l
Base excess: -2 – 2 mmol/lIn this particular case, the patient’s medical history raises concerns about a possible diagnosis of diabetic ketoacidosis (DKA). The relevant ABG findings are as follows:
Normal PO2
Low pH (acidaemia)
Low PCO2
Low bicarbonate
Raised lactateThe anion gap refers to the concentration of unmeasured anions in the plasma. It is calculated by subtracting the primary measured cations from the primary measured anions in the serum. The reference range for anion gap varies depending on the measurement methodology but typically falls between 8 to 16 mmol/L.
To calculate her anion gap, we can use the formula:
Anion gap = [Na+] – [Cl-] – [HCO3-]
Using the provided values, her anion gap can be calculated as:
Anion gap = [149] – [100] – [17]
Anion gap = 32Therefore, it is evident that she has a raised anion gap metabolic acidosis.
It is likely that she is experiencing a type B lactic acidosis secondary to diabetic ketoacidosis. Some potential causes of type A and type B lactic acidosis are listed below:
Type A lactic acidosis:
– Shock (including septic shock)
– Left ventricular failure
– Severe anemia
– Asphyxia
– Cardiac arrest
– Carbon monoxide poisoning
– Respiratory failure
– Severe asthma and COPD
– Regional hypoperfusionType B lactic acidosis:
– Renal failure
– Liver failure
– Sepsis (non-hypoxic sepsis)
– Thiamine deficiency
– Alcoholic ketoacidosis
– Diabetic ketoacidosis
– Cyanide poisoning
– Methanol poisoning
– Biguanide poisoning -
This question is part of the following fields:
- Endocrinology
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Question 12
Correct
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A 45-year-old woman presents with overall fatigue and increased skin pigmentation. She has a history of bilateral adrenalectomy for Cushing's syndrome 10 years ago. During the examination of her visual fields, a bitemporal hemianopia is discovered.
What is the MOST LIKELY single biochemical finding in this scenario?Your Answer: Elevated ACTH levels
Explanation:Nelson’s syndrome is a rare condition that occurs many years after a bilateral adrenalectomy for Cushing’s syndrome. It is believed to develop due to the loss of the normal negative feedback control that suppresses high cortisol levels. As a result, the hypothalamus starts producing CRH again, which stimulates the growth of a pituitary adenoma that produces adrenocorticotropic hormone (ACTH).
Only 15-20% of patients who undergo bilateral adrenalectomy will develop this condition, and it is now rarely seen as the procedure is no longer commonly performed.
The symptoms and signs of Nelson’s syndrome are related to the growth of the pituitary adenoma and the increased production of ACTH and melanocyte-stimulating hormone (MSH) from the adenoma. These may include headaches, visual field defects (up to 50% of cases), increased skin pigmentation, and the possibility of hypopituitarism.
ACTH levels will be significantly elevated (usually >500 ng/L). Thyroxine, TSH, gonadotrophin, and sex hormone levels may be low. Prolactin levels may be high, but not as high as with a prolactin-producing tumor. MRI or CT scanning can be helpful in identifying the presence of an expanding pituitary mass.
The treatment of choice for Nelson’s syndrome is trans-sphenoidal surgery.
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This question is part of the following fields:
- Endocrinology
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Question 13
Correct
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A 5-year-old girl is brought into the Emergency Department with stomach pain and vomiting. Her mother informs you that she has been losing weight recently and has been drinking a lot of fluids and urinating frequently. During the examination, you observe that she is drowsy and visibly dehydrated. She is breathing deeply and rapidly. A blood glucose test reveals very high levels. The urine dipstick shows 3+ ketones, and a venous blood gas test indicates a pH of 7.14. The diagnosis is diabetic ketoacidosis.
How long should it take to correct this fluid deficit?Your Answer: 48 hours
Explanation:The most probable diagnosis in this case is diabetic ketoacidosis (DKA). To confirm the diagnosis, it is necessary to establish that his blood glucose levels are elevated, he has significant ketonuria or ketonaemia, and that he is acidotic.
DKA is a life-threatening condition that occurs when there is a lack of insulin, leading to an inability to metabolize glucose. This results in high blood sugar levels and an osmotic diuresis, causing excessive thirst and increased urine production. Dehydration becomes inevitable when the urine output exceeds the patient’s ability to drink. Additionally, without insulin, fat becomes the primary energy source, leading to the production of large amounts of ketones and metabolic acidosis.
The key features of DKA include hyperglycemia (blood glucose > 11 mmol/l), ketonaemia (> 3 mmol/l) or significant ketonuria (> 2+ on urine dipstick), and acidosis (bicarbonate < 15 mmol/l and/or venous pH < 7.3). Clinical symptoms of DKA include nausea, vomiting, excessive thirst, excessive urine production, abdominal pain, signs of dehydration, a smell of ketones on breath (similar to pear drops), deep and rapid respiration (Kussmaul breathing), confusion or reduced consciousness, and tachycardia, hypotension, and shock. Investigations that should be performed include blood glucose measurement, urine dipstick (which will show marked glycosuria and ketonuria), blood ketone assay (more sensitive and specific than urine dipstick), blood tests (full blood count and urea and electrolytes), and arterial or venous blood gas analysis to assess for metabolic acidosis. The main principles of managing DKA are as follows: – Fluid boluses should only be given to reverse signs of shock and should be administered slowly in 10 ml/kg aliquots. If there are no signs of shock, fluid boluses should not be given, and specialist advice should be sought if a second bolus is required.
– Rehydration should be done with replacement therapy over 48 hours after signs of shock have been reversed.
– The first 20 ml/kg of fluid resuscitation should be given in addition to replacement fluid calculations and should not be subtracted from the calculations for the 48-hour fluid replacement.
– If a child in DKA shows signs of hypotensive shock, the use of inotropes may be considered. -
This question is part of the following fields:
- Endocrinology
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Question 14
Correct
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A 48-year-old presents to the emergency department complaining of severe headache, excessive sweating, and episodes of blurred vision. The triage observations are as follows:
Blood pressure: 234/138 mmHg
Pulse rate: 106 bpm
Respiration rate: 18 bpm
Oxygen saturations: 97% on air
Temperature: 37.3ºC
The patient informs you that they have been referred for hypertension investigation and are awaiting the results of a 24-hour urine collection. You come across a letter from one of the cardiologists who requested a 24-hour urine collection for catecholamines, metanephrines, and normetanephrines due to suspicion of phaeochromocytoma.
Which of the following medications would be the most appropriate choice to lower the blood pressure in a patient with phaeochromocytoma?Your Answer: Phentolamine
Explanation:In this scenario, a 48-year-old patient presents to the emergency department with severe headache, excessive sweating, and episodes of blurred vision. The patient’s triage observations reveal a significantly elevated blood pressure of 234/138 mmHg. The patient also mentions that they are awaiting the results of a 24-hour urine collection for hypertension investigation, specifically for catecholamines, metanephrines, and normetanephrines, as there is suspicion of phaeochromocytoma.
Phaeochromocytoma is a rare tumor that arises from the adrenal glands and can cause excessive release of catecholamines, such as adrenaline and noradrenaline. This leads to symptoms like severe hypertension, headache, sweating, and palpitations.
Given the patient’s presentation and suspicion of phaeochromocytoma, the most appropriate medication choice to lower the blood pressure would be phentolamine. Phentolamine is an alpha-adrenergic antagonist that blocks the effects of catecholamines on blood vessels, resulting in vasodilation and a decrease in blood pressure.
Hydralazine, magnesium sulfate, and glyceryl trinitrate are not the most appropriate choices in this scenario. Hydralazine is a direct vasodilator that acts on smooth muscle to relax blood vessels, but it does not specifically target the effects of catecholamines. Magnesium sulfate is commonly used for conditions like preeclampsia and eclampsia, but it does not directly address the underlying cause of hypertension in phaeochromocytoma. Glyceryl trinitrate, also known as nitroglycerin, is primarily used for the management of angina and does not specifically target the effects of catecholamines.
Diazepam is a benzodiazepine that has sedative and anxiolytic properties but does not directly lower blood pressure or address the underlying cause of hypertension in phaeochromocytoma.
Further Reading:
A hypertensive emergency is characterized by a significant increase in blood pressure accompanied by acute or progressive damage to organs. While there is no specific blood pressure value that defines a hypertensive emergency, systolic blood pressure is typically above 180 mmHg and/or diastolic blood pressure is above 120 mmHg. The most common presentations of hypertensive emergencies include cerebral infarction, pulmonary edema, encephalopathy, and congestive cardiac failure. Less common presentations include intracranial hemorrhage, aortic dissection, and pre-eclampsia/eclampsia.
The signs and symptoms of hypertensive emergencies can vary widely due to the potential dysfunction of every physiological system. Some common signs and symptoms include headache, nausea and/or vomiting, chest pain, arrhythmia, proteinuria, signs of acute kidney failure, epistaxis, dyspnea, dizziness, anxiety, confusion, paraesthesia or anesthesia, and blurred vision. Clinical assessment focuses on detecting acute or progressive damage to the cardiovascular, renal, and central nervous systems.
Investigations that are essential in evaluating hypertensive emergencies include U&Es (electrolyte levels), urinalysis, ECG, and CXR. Additional investigations may be considered depending on the suspected underlying cause, such as a CT head for encephalopathy or new onset confusion, CT thorax for suspected aortic dissection, and CT abdomen for suspected phaeochromocytoma. Plasma free metanephrines, urine total catecholamines, vanillylmandelic acid (VMA), and metanephrine may be tested if phaeochromocytoma is suspected. Urine screening for cocaine and/or amphetamines may be appropriate in certain cases, as well as an endocrine screen for Cushing’s syndrome.
The management of hypertensive emergencies involves cautious reduction of blood pressure to avoid precipitating renal, cerebral, or coronary ischemia. Staged blood pressure reduction is typically the goal, with an initial reduction in mean arterial pressure (MAP) by no more than 25% in the first hour. Further gradual reduction to a systolic blood pressure of 160 mmHg and diastolic blood pressure of 100 mmHg over the next 2 to 6 hours is recommended. Initial management involves treatment with intravenous antihypertensive agents in an intensive care setting with appropriate monitoring.
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This question is part of the following fields:
- Endocrinology
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Question 15
Correct
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A 40-year-old male patient presents with a history of dizziness and fainting episodes. He has also been suffering from a mild flu-like illness for the past few days. He had a syncopal episode in the department and was moved into the resuscitation area. His observations are as follows: Temperature 38.4°C, HR 112, BP 78/44, oxygen saturation 98% on high-flow oxygen, GCS 14/15, BM 1.5.
His initial blood results are shown below:
Na+: 118 mmol/l
K+: 6.1 mmol/l
Urea: 11.6 mmol/l
Creatinine: 132 mmol/l
What is the SINGLE most likely diagnosis?Your Answer: Addisonian crisis
Explanation:This patient has presented with an Addisonian crisis, which is a rare but potentially catastrophic condition if not diagnosed promptly. It is more commonly seen in women than men and typically occurs between the ages of 30 and 50.
Addison’s disease is caused by insufficient production of steroid hormones by the adrenal glands, affecting the production of glucocorticoids, mineralocorticoids, and sex steroids. The main causes of Addison’s disease include autoimmune adrenalitis (accounting for 80% of cases), bilateral adrenalectomy, Waterhouse-Friderichsen syndrome (hemorrhage into the adrenal glands), and tuberculosis.
The most common trigger for an Addisonian crisis in patients with Addison’s disease is the intentional or accidental withdrawal of steroid therapy. Other factors that can precipitate a crisis include infection, trauma, myocardial infarction, cerebral infarction, asthma, hypothermia, and alcohol abuse.
Clinical features of Addison’s disease include weakness, lethargy, hypotension (especially orthostatic hypotension), nausea, vomiting, weight loss, reduced axillary and pubic hair, depression, and hyperpigmentation (particularly in palmar creases, buccal mucosa, and exposed areas). In an Addisonian crisis, the main symptoms are usually hypoglycemia and shock, characterized by tachycardia, peripheral vasoconstriction, hypotension, altered consciousness, and even coma.
Biochemical markers of Addison’s disease typically include increased ACTH levels (as a compensatory response to stimulate the adrenal glands), elevated serum renin levels, hyponatremia, hyperkalemia, hypercalcemia, hypoglycemia, and metabolic acidosis. Confirmatory investigations may involve the Synacthen test, plasma ACTH level measurement, plasma renin level measurement, and testing for adrenocortical antibodies.
Management of Addison’s disease should be overseen by an Endocrinologist. Treatment usually involves the administration of hydrocortisone, fludrocortisone, and dehydroepiandrosterone. Some patients may also require thyroxine if there is concurrent hypothalamic-pituitary disease. Treatment is lifelong, and patients should carry a steroid card and MedicAlert bracelet to alert healthcare professionals about their condition and the potential for an Addisonian crisis.
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This question is part of the following fields:
- Endocrinology
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Question 16
Correct
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A patient presents with abdominal pain and confusion. They have a history of Addison’s disease but recently ran out of their steroid medication. You suspect an Addisonian crisis.
What is the most frequent cause of Addison’s disease?Your Answer: Autoimmune adrenalitis
Explanation:Addison’s disease can be attributed to various underlying causes. The most common cause, accounting for approximately 80% of cases, is autoimmune adrenalitis. This occurs when the body’s immune system mistakenly attacks the adrenal glands. Another cause is bilateral adrenalectomy, which involves the surgical removal of both adrenal glands. Additionally, Addison’s disease can be triggered by a condition known as Waterhouse-Friderichsen syndrome, which involves bleeding into the adrenal glands. Tuberculosis, a bacterial infection, is also recognized as a potential cause of this disease. Lastly, although rare, congenital adrenal hyperplasia can contribute to the development of Addison’s disease.
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This question is part of the following fields:
- Endocrinology
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Question 17
Correct
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A 10-year-old girl comes in with excessive thirst, frequent urination, and increased thirst. She has been feeling very fatigued lately and has experienced significant weight loss. Blood tests show normal levels of urea and electrolytes, but her bicarbonate level is 18 mmol/l (reference range 22-26 mmol/l). A urine dipstick test reveals 2+ protein and 3+ ketones.
What is the SINGLE most probable diagnosis?Your Answer: Type 1 diabetes mellitus
Explanation:This child is displaying a typical pattern of symptoms for type I diabetes mellitus. He has recently experienced increased urination, excessive thirst, weight loss, and fatigue. Blood tests have revealed metabolic acidosis, and the presence of ketones in his urine indicates the development of diabetic ketoacidosis.
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This question is part of the following fields:
- Endocrinology
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Question 18
Correct
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A 70-year-old woman from a retirement community experiences a sudden collapse. Her blood sugar level is measured and found to be 2.2. She has a medical history of diabetes mellitus.
Which ONE medication is most likely to have caused her episode of hypoglycemia?Your Answer: Pioglitazone
Explanation:Of all the medications mentioned in this question, only pioglitazone is known to be a potential cause of hypoglycemia. Glucagon, on the other hand, is specifically used as a treatment for hypoglycemia. The remaining medications mentioned are antidiabetic drugs that do not typically lead to hypoglycemia when used alone.
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This question is part of the following fields:
- Endocrinology
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Question 19
Correct
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You evaluate a 45-year-old man with a history of difficult-to-control hypertension. His initial diagnosis was made after ambulatory blood pressure monitoring. He is currently taking Lisinopril 10 mg once daily and Amlodipine 10 mg once daily. Despite this treatment, his blood pressure today is 156/98. On examination, he appears normal and is otherwise in good health. A recent blood test shows the following results:
Sodium: 145 mmol/L (135-147 mmol/L)
Potassium: 3.2 mmol/L (3.5-5.5 mmol/L)
Urea: 6.3 mmol/L (2.0-6.6 mmol/L)
Creatinine: 88 mmol/L (75-125 mmol/L)
What is the MOST LIKELY diagnosis?Your Answer: Primary hyperaldosteronism
Explanation:The most probable diagnosis in this case is primary hyperaldosteronism, which is caused by either an adrenal adenoma (Conn’s syndrome) or bilateral idiopathic adrenal hyperplasia. Conn’s syndrome is likely in a patient who has difficult-to-control hypertension, low levels of potassium (hypokalaemia), and elevated or high normal levels of sodium. If the aldosterone:renin ratio is raised (>30), it further suggests primary hyperaldosteronism. CT scanning can be used to differentiate between an adrenal adenoma and adrenal hyperplasia. Treatment for hyperaldosteronism caused by an adenoma typically involves 4-6 weeks of spironolactone therapy followed by surgical removal of the adenoma. Adrenal hyperplasia usually responds well to potassium-sparing diuretics alone, such as spironolactone or amiloride.
Renal artery stenosis could also be suspected in a case of resistant hypertension, but it would be expected to cause a decline in renal function when taking a full dose of an ACE inhibitor like ramipril. However, in this case, the patient’s renal function is completely normal.
Phaeochromocytoma is associated with symptoms such as headaches, palpitations, tremors, and excessive sweating. The hypertension in phaeochromocytoma tends to occur in episodes. Since these symptoms are absent in this patient, a diagnosis of phaeochromocytoma is unlikely.
Cushing’s syndrome is characterized by various other clinical features, including weight gain, central obesity, a hump-like accumulation of fat on the back (buffalo hump), muscle wasting in the limbs, excessive hair growth (hirsutism), thinning of the skin, easy bruising, acne, and depression. Since this patient does not exhibit any of these features, Cushing’s syndrome is unlikely.
White coat syndrome is an unlikely diagnosis in this case because the initial diagnosis of hypertension was made based on ambulatory blood pressure monitoring.
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This question is part of the following fields:
- Endocrinology
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Question 20
Incorrect
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A 52 year old male is brought into the emergency department acutely ill and is transferred to resus. Your consultant suspects thyrotoxic crisis and instructs you to prepare the necessary medication. What drugs are typically administered during the initial treatment of thyrotoxic crisis?
Your Answer: Antithyroid drug, amiodarone, benzodiazepine and corticosteroids
Correct Answer: Antithyroid drug, beta blocker, corticosteroids and iodine solution
Explanation:Thyroid storm, also known as thyrotoxic crisis, is a rare and dangerous complication of hyperthyroidism. The initial management of this condition involves the use of specific medications. These medications include a beta blocker, a corticosteroid, an antithyroid drug, and an iodine solution.
The beta blocker used is typically propranolol, which is administered intravenously at a dose of 1 mg over 1 minute. If a beta blocker is contraindicated, a calcium channel blocker such as diltiazem may be used instead, at a dose of 0.25 mg/kg over 2 minutes.
For corticosteroids, hydrocortisone is commonly used and given intravenously at a dose of 200 mg. Alternatively, dexamethasone can be used at a dose of 2 mg intravenously.
The antithyroid drug used is usually propylthiouracil, which is given orally, through a nasogastric tube, or rectally, at a dose of 200 mg.
An iodine solution, specifically Lugol’s iodine, is also part of the initial management. However, it should not be administered until at least 1 hour after the antithyroid drug has been given. This is because iodine can exacerbate thyrotoxicosis by stimulating thyroid hormone synthesis. Propylthiouracil, on the other hand, inhibits the normal interactions of iodine and peroxidase with thyroglobulin, preventing the formation of T4 and T3. Therefore, it is given first and allowed time to take effect before iodine is administered.
Further Reading:
The thyroid gland is an endocrine organ located in the anterior neck. It consists of two lobes connected by an isthmus. The gland produces hormones called thyroxine (T4) and triiodothyronine (T3), which regulate energy use, protein synthesis, and the body’s sensitivity to other hormones. The production of T4 and T3 is stimulated by thyroid-stimulating hormone (TSH) secreted by the pituitary gland, which is in turn stimulated by thyrotropin-releasing hormone (TRH) from the hypothalamus.
Thyroid disorders can occur when there is an imbalance in the production or regulation of thyroid hormones. Hypothyroidism is characterized by a deficiency of thyroid hormones, while hyperthyroidism is characterized by an excess. The most common cause of hypothyroidism is autoimmune thyroiditis, also known as Hashimoto’s thyroiditis. It is more common in women and is often associated with goiter. Other causes include subacute thyroiditis, atrophic thyroiditis, and iodine deficiency. On the other hand, the most common cause of hyperthyroidism is Graves’ disease, which is also an autoimmune disorder. Other causes include toxic multinodular goiter and subacute thyroiditis.
The symptoms and signs of thyroid disorders can vary depending on whether the thyroid gland is underactive or overactive. In hypothyroidism, common symptoms include weight gain, lethargy, cold intolerance, and dry skin. In hyperthyroidism, common symptoms include weight loss, restlessness, heat intolerance, and increased sweating. Both hypothyroidism and hyperthyroidism can also affect other systems in the body, such as the cardiovascular, gastrointestinal, and neurological systems.
Complications of thyroid disorders can include dyslipidemia, metabolic syndrome, coronary heart disease, heart failure, subfertility and infertility, impaired special senses, and myxedema coma in severe cases of hypothyroidism. In hyperthyroidism, complications can include Graves’ orbitopathy, compression of the esophagus or trachea by goiter, thyrotoxic periodic paralysis, arrhythmias, osteoporosis, mood disorders, and increased obstetric complications.
Myxedema coma is a rare and life-threatening complication of severe hypothyroidism. It can be triggered by factors such as infection or physiological insult and presents with lethargy, bradycardia, hypothermia, hypotension, hypoventilation, altered mental state, seizures and/or coma.
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This question is part of the following fields:
- Endocrinology
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Question 21
Correct
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Your consultant requests that you organize a teaching session on thyroid dysfunction and the interpretation of thyroid function tests. Which of the subsequent biochemical patterns is indicative of primary hypothyroidism?
Your Answer: High thyroid stimulating hormone (TSH) & low thyroxine (T4)
Explanation:The levels of thyroid stimulating hormone (TSH) and thyroxine (T4) are both below the normal range.
Further Reading:
The thyroid gland is an endocrine organ located in the anterior neck. It consists of two lobes connected by an isthmus. The gland produces hormones called thyroxine (T4) and triiodothyronine (T3), which regulate energy use, protein synthesis, and the body’s sensitivity to other hormones. The production of T4 and T3 is stimulated by thyroid-stimulating hormone (TSH) secreted by the pituitary gland, which is in turn stimulated by thyrotropin-releasing hormone (TRH) from the hypothalamus.
Thyroid disorders can occur when there is an imbalance in the production or regulation of thyroid hormones. Hypothyroidism is characterized by a deficiency of thyroid hormones, while hyperthyroidism is characterized by an excess. The most common cause of hypothyroidism is autoimmune thyroiditis, also known as Hashimoto’s thyroiditis. It is more common in women and is often associated with goiter. Other causes include subacute thyroiditis, atrophic thyroiditis, and iodine deficiency. On the other hand, the most common cause of hyperthyroidism is Graves’ disease, which is also an autoimmune disorder. Other causes include toxic multinodular goiter and subacute thyroiditis.
The symptoms and signs of thyroid disorders can vary depending on whether the thyroid gland is underactive or overactive. In hypothyroidism, common symptoms include weight gain, lethargy, cold intolerance, and dry skin. In hyperthyroidism, common symptoms include weight loss, restlessness, heat intolerance, and increased sweating. Both hypothyroidism and hyperthyroidism can also affect other systems in the body, such as the cardiovascular, gastrointestinal, and neurological systems.
Complications of thyroid disorders can include dyslipidemia, metabolic syndrome, coronary heart disease, heart failure, subfertility and infertility, impaired special senses, and myxedema coma in severe cases of hypothyroidism. In hyperthyroidism, complications can include Graves’ orbitopathy, compression of the esophagus or trachea by goiter, thyrotoxic periodic paralysis, arrhythmias, osteoporosis, mood disorders, and increased obstetric complications.
Myxedema coma is a rare and life-threatening complication of severe hypothyroidism. It can be triggered by factors such as infection or physiological insult and presents with lethargy, bradycardia, hypothermia, hypotension, hypoventilation, altered mental state, seizures and/or coma.
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This question is part of the following fields:
- Endocrinology
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Question 22
Correct
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In which age group does Addison's disease typically first manifest?
Your Answer: Adults aged 30-50 years of age
Explanation:Adrenal insufficiency, also known as Addison’s disease, is a condition that is more frequently observed in women and typically manifests in individuals aged 30-50 years. In the UK alone, nearly 9000 individuals have received a diagnosis for this disorder. While it can affect people of all ages, it predominantly occurs in women and those within the 30-50 age range.
Further Reading:
Addison’s disease, also known as primary adrenal insufficiency or hypoadrenalism, is a rare disorder caused by the destruction of the adrenal cortex. This leads to reduced production of glucocorticoids, mineralocorticoids, and adrenal androgens. The deficiency of cortisol results in increased production of adrenocorticotropic hormone (ACTH) due to reduced negative feedback to the pituitary gland. This condition can cause metabolic disturbances such as hyperkalemia, hyponatremia, hypercalcemia, and hypoglycemia.
The symptoms of Addison’s disease can vary but commonly include fatigue, weight loss, muscle weakness, and low blood pressure. It is more common in women and typically affects individuals between the ages of 30-50. The most common cause of primary hypoadrenalism in developed countries is autoimmune destruction of the adrenal glands. Other causes include tuberculosis, adrenal metastases, meningococcal septicaemia, HIV, and genetic disorders.
The diagnosis of Addison’s disease is often suspected based on low cortisol levels and electrolyte abnormalities. The adrenocorticotropic hormone stimulation test is commonly used for confirmation. Other investigations may include adrenal autoantibodies, imaging scans, and genetic screening.
Addisonian crisis is a potentially life-threatening condition that occurs when there is an acute deficiency of cortisol and aldosterone. It can be the first presentation of undiagnosed Addison’s disease. Precipitating factors of an Addisonian crisis include infection, dehydration, surgery, trauma, physiological stress, pregnancy, hypoglycemia, and acute withdrawal of long-term steroids. Symptoms of an Addisonian crisis include malaise, fatigue, nausea or vomiting, abdominal pain, fever, muscle pains, dehydration, confusion, and loss of consciousness.
There is no fixed consensus on diagnostic criteria for an Addisonian crisis, as symptoms are non-specific. Investigations may include blood tests, blood gas analysis, and septic screens if infection is suspected. Management involves administering hydrocortisone and fluids. Hydrocortisone is given parenterally, and the dosage varies depending on the age of the patient. Fluid resuscitation with saline is necessary to correct any electrolyte disturbances and maintain blood pressure. The underlying cause of the crisis should also be identified and treated. Close monitoring of sodium levels is important to prevent complications such as osmotic demyelination syndrome.
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This question is part of the following fields:
- Endocrinology
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Question 23
Correct
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A 70 year old male presents to the emergency department feeling generally fatigued. On taking a history the patient reports a decline in his skin and hair condition over the past few months. Thyroid function tests are ordered which show the following:
Test Result Normal range
TSH 6.2 miU/L 0.27 - 4.2 miU/L
Free T4 13 pmol/L 12.0 - 22.0 pmol/L
What is the diagnosis?Your Answer: Subclinical hypothyroidism
Explanation:Subclinical hypothyroidism is a condition where the thyroid-stimulating hormone (TSH) levels are higher than normal, but the levels of free thyroxine (T4) are still within the normal range. On the other hand, subclinical hyperthyroidism is a condition where the TSH levels are lower than normal, but the levels of free triiodothyronine (T3) and free thyroxine (T4) are still within the normal range.
Further Reading:
The thyroid gland is an endocrine organ located in the anterior neck. It consists of two lobes connected by an isthmus. The gland produces hormones called thyroxine (T4) and triiodothyronine (T3), which regulate energy use, protein synthesis, and the body’s sensitivity to other hormones. The production of T4 and T3 is stimulated by thyroid-stimulating hormone (TSH) secreted by the pituitary gland, which is in turn stimulated by thyrotropin-releasing hormone (TRH) from the hypothalamus.
Thyroid disorders can occur when there is an imbalance in the production or regulation of thyroid hormones. Hypothyroidism is characterized by a deficiency of thyroid hormones, while hyperthyroidism is characterized by an excess. The most common cause of hypothyroidism is autoimmune thyroiditis, also known as Hashimoto’s thyroiditis. It is more common in women and is often associated with goiter. Other causes include subacute thyroiditis, atrophic thyroiditis, and iodine deficiency. On the other hand, the most common cause of hyperthyroidism is Graves’ disease, which is also an autoimmune disorder. Other causes include toxic multinodular goiter and subacute thyroiditis.
The symptoms and signs of thyroid disorders can vary depending on whether the thyroid gland is underactive or overactive. In hypothyroidism, common symptoms include weight gain, lethargy, cold intolerance, and dry skin. In hyperthyroidism, common symptoms include weight loss, restlessness, heat intolerance, and increased sweating. Both hypothyroidism and hyperthyroidism can also affect other systems in the body, such as the cardiovascular, gastrointestinal, and neurological systems.
Complications of thyroid disorders can include dyslipidemia, metabolic syndrome, coronary heart disease, heart failure, subfertility and infertility, impaired special senses, and myxedema coma in severe cases of hypothyroidism. In hyperthyroidism, complications can include Graves’ orbitopathy, compression of the esophagus or trachea by goiter, thyrotoxic periodic paralysis, arrhythmias, osteoporosis, mood disorders, and increased obstetric complications.
Myxedema coma is a rare and life-threatening complication of severe hypothyroidism. It can be triggered by factors such as infection or physiological insult and presents with lethargy, bradycardia, hypothermia, hypotension, hypoventilation, altered mental state, seizures and/or coma.
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This question is part of the following fields:
- Endocrinology
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Question 24
Correct
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A 35-year-old man presents with occasional episodes of excessive sweating, rapid heartbeat, and a sense of panic and anxiety. He measured his blood pressure at home during one of these episodes and found it to be 190/110 mmHg. You measure it today and find it to be normal at 118/72 mmHg. He mentions that his brother has a similar condition, but he can't recall the name of it.
What is the most suitable initial investigation for this patient?Your Answer: Radioimmunoassay for urinary/plasma metanephrines
Explanation:This patient is displaying symptoms and signs that are consistent with a diagnosis of phaeochromocytoma. Phaeochromocytoma is a rare functional tumor that originates from chromaffin cells in the adrenal medulla. There are also less common tumors called extra-adrenal paragangliomas, which develop in the ganglia of the sympathetic nervous system. Both types of tumors secrete catecholamines, leading to symptoms and signs associated with hyperactivity of the sympathetic nervous system.
The most common initial symptom is hypertension, which can be either sustained or paroxysmal. Other symptoms tend to be intermittent and can occur frequently or infrequently. As the disease progresses, these symptoms usually become more severe and frequent.
In addition to hypertension, patients with phaeochromocytoma may experience the following clinical features: headache, profuse sweating, palpitations or rapid heartbeat, tremors, fever, nausea and vomiting, anxiety and panic attacks, a sense of impending doom, epigastric or flank pain, constipation, hypertensive retinopathy, postural hypotension due to volume contraction, cardiomyopathy, and café au lait spots.
To confirm a suspected diagnosis of phaeochromocytoma, elevated levels of metanephrines (catecholamine metabolites) can be measured in the blood or urine. This can be done through methods such as a 24-hour urine collection for free catecholamines, vanillylmandelic acid (VMA), and metanephrines, high-performance liquid chromatography for catecholamines in plasma and/or urine, or radioimmunoassay (RIA) for urinary/plasma metanephrines.
Once the diagnosis of phaeochromocytoma is biochemically confirmed, imaging methods can be used to locate the tumor. The first imaging modality to be used is a CT scan, which has an overall sensitivity of 89%. An MRI scan is the most sensitive modality for identifying the tumor, especially in cases of extra-adrenal tumors or metastatic disease, with an overall sensitivity of 98%. In cases where CT or MRI does not show a tumor, a nuclear medicine scan such as MIBG scintigraphy can be useful.
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This question is part of the following fields:
- Endocrinology
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Question 25
Correct
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A 3-month-old girl presents with vomiting, poor weight gain, and decreased muscle tone. She is hypotensive and has a rapid heart rate. On examination, you notice that she has enlarged scrotum and increased pigmentation. Blood tests show high potassium, low sodium, and elevated 17-hydroxyprogesterone levels. Venous blood gas analysis reveals the presence of metabolic acidosis.
What is the SINGLE most probable diagnosis?Your Answer: Congenital adrenal hyperplasia
Explanation:Congenital adrenal hyperplasia (CAH) is a group of inherited disorders that are caused by autosomal recessive genes. The majority of affected patients, over 90%, have a deficiency of the enzyme 21-hydroxylase. This enzyme is encoded by the 21-hydroxylase gene, which is located on chromosome 6p21 within the HLA histocompatibility complex. The second most common cause of CAH is a deficiency of the enzyme 11-beta-hydroxylase. The condition is rare, with an incidence of approximately 1 in 500 births in the UK. It is more prevalent in the offspring of consanguineous marriages.
The deficiency of 21-hydroxylase leads to a deficiency of cortisol and/or aldosterone, as well as an excess of precursor steroids. As a result, there is an increased secretion of ACTH from the anterior pituitary, leading to adrenocortical hyperplasia.
The severity of CAH varies depending on the degree of 21-hydroxylase deficiency. Female infants often exhibit ambiguous genitalia, such as clitoral hypertrophy and labial fusion. Male infants may have an enlarged scrotum and/or scrotal pigmentation. Hirsutism, or excessive hair growth, occurs in 10% of cases.
Boys with CAH often experience a salt-losing adrenal crisis at around 1-3 weeks of age. This crisis is characterized by symptoms such as vomiting, weight loss, floppiness, and circulatory collapse.
The diagnosis of CAH can be made by detecting markedly elevated levels of the metabolic precursor 17-hydroxyprogesterone. Neonatal screening is possible through the detection of persistently elevated 17-hydroxyprogesterone.
In infants presenting with a salt-losing crisis, the following biochemical abnormalities are typically observed: hyponatremia (low sodium levels), hyperkalemia (high potassium levels), metabolic acidosis, and hypoglycemia.
Boys experiencing a salt-losing crisis will require fluid resuscitation, intravenous dextrose, and intravenous hydrocortisone. Affected females may require corrective surgery for their external genitalia. However, they have an intact uterus and ovaries and are able to have children.
The long-term management of CAH involves lifelong replacement of hydrocortisone to suppress ACTH levels.
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This question is part of the following fields:
- Endocrinology
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Question 26
Correct
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A 72-year-old man presents to the Emergency Department anxious, confused, and agitated. He has also vomited several times. He has recently been prescribed a course of amoxicillin for a presumed chest infection by his GP. You are unable to obtain a coherent history from him, but he has his regular medications with him, which include aspirin, simvastatin, and carbimazole. He has a friend with him who states he stopped taking his medications a few days ago. His vital signs are as follows: temperature 38.9°C, heart rate 138, respiratory rate 23, blood pressure 173/96, and oxygen saturation 97% on room air.
Which of the following medications would be most appropriate to prescribe in this case?Your Answer: Carbimazole
Explanation:Thyroid storm is a rare condition that affects only 1-2% of patients with hyperthyroidism. However, it is crucial to diagnose it promptly because it has a high mortality rate of approximately 10%. Thyroid storm is often triggered by a physiological stressor, such as stopping antithyroid therapy prematurely, recent surgery or radio-iodine treatment, infections (especially chest infections), trauma, diabetic ketoacidosis or hyperosmolar diabetic crisis, thyroid hormone overdose, pre-eclampsia. It typically occurs in patients with Graves’ disease or toxic multinodular goitre and presents with sudden and severe hyperthyroidism. Symptoms include high fever (over 41°C), dehydration, rapid heart rate (greater than 140 beats per minute) with or without irregular heart rhythms, low blood pressure, congestive heart failure, nausea, jaundice, vomiting, diarrhea, abdominal pain, confusion, agitation, delirium, psychosis, seizures, or coma.
To diagnose thyroid storm, various blood tests should be conducted, including a full blood count, urea and electrolytes, blood glucose, coagulation screen, CRP, and thyroid profile (T4/T3 and TSH). A bone profile/calcium test should also be done as 10% of patients develop hypocalcemia. Blood cultures should be taken as well. Other important investigations include a urine dipstick/MC&S, chest X-ray, and ECG.
The management of thyroid storm involves several steps. Intravenous fluids, such as 1-2 liters of 0.9% saline, should be administered. Airway support and management should be provided as necessary. A nasogastric tube should be inserted if the patient is vomiting. Urgent referral for inpatient management is essential. Paracetamol (1 g PO/IV) can be given to reduce fever. Benzodiazepines, such as diazepam (5-20 mg PO/IV), can be used for sedation. Steroids, like hydrocortisone (100 mg IV), may be necessary if there is co-existing adrenal suppression. Antibiotics should be prescribed if there is an intercurrent infection. Beta-blockers, such as propranolol (80 mg PO), can help control heart rate. High-dose carbimazole (45-60 mg/day) is recommended.
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This question is part of the following fields:
- Endocrinology
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Question 27
Correct
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Your consultant requests you to arrange a teaching session on secondary causes of hypertension. Which of the subsequent electrolyte abnormalities would be in line with a diagnosis of Conn's syndrome?
Your Answer: Hypokalaemia and hypernatraemia
Explanation:Patients with primary hyperaldosteronism typically present with hypertension and hypokalemia. This is due to the fact that aldosterone encourages the reabsorption of sodium and the excretion of potassium, leading to an imbalance in these electrolytes. Additionally, hypernatremia, or high levels of sodium in the blood, is often observed in these patients.
Further Reading:
Hyperaldosteronism is a condition characterized by excessive production of aldosterone by the adrenal glands. It can be classified into primary and secondary hyperaldosteronism. Primary hyperaldosteronism, also known as Conn’s syndrome, is typically caused by adrenal hyperplasia or adrenal tumors. Secondary hyperaldosteronism, on the other hand, is a result of high renin levels in response to reduced blood flow across the juxtaglomerular apparatus.
Aldosterone is the main mineralocorticoid steroid hormone produced by the adrenal cortex. It acts on the distal renal tubule and collecting duct of the nephron, promoting the reabsorption of sodium ions and water while secreting potassium ions.
The causes of hyperaldosteronism vary depending on whether it is primary or secondary. Primary hyperaldosteronism can be caused by adrenal adenoma, adrenal hyperplasia, adrenal carcinoma, or familial hyperaldosteronism. Secondary hyperaldosteronism can be caused by renal artery stenosis, reninoma, renal tubular acidosis, nutcracker syndrome, ectopic tumors, massive ascites, left ventricular failure, or cor pulmonale.
Clinical features of hyperaldosteronism include hypertension, hypokalemia, metabolic alkalosis, hypernatremia, polyuria, polydipsia, headaches, lethargy, muscle weakness and spasms, and numbness. It is estimated that hyperaldosteronism is present in 5-10% of patients with hypertension, and hypertension in primary hyperaldosteronism is often resistant to drug treatment.
Diagnosis of hyperaldosteronism involves various investigations, including U&Es to assess electrolyte disturbances, aldosterone-to-renin plasma ratio (ARR) as the gold standard diagnostic test, ECG to detect arrhythmia, CT/MRI scans to locate adenoma, fludrocortisone suppression test or oral salt testing to confirm primary hyperaldosteronism, genetic testing to identify familial hyperaldosteronism, and adrenal venous sampling to determine lateralization prior to surgery.
Treatment of primary hyperaldosteronism typically involves surgical adrenalectomy for patients with unilateral primary aldosteronism. Diet modification with sodium restriction and potassium supplementation may also be recommended.
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This question is part of the following fields:
- Endocrinology
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Question 28
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A 35-year-old man with a past of episodes of excessive sweating, rapid heartbeat, and sudden high blood pressure is diagnosed with a phaeochromocytoma.
A phaeochromocytoma is a functioning tumor that originates from cells in which of the following?Your Answer: Adrenal medulla
Explanation:A phaeochromocytoma is an uncommon functional tumor that develops from chromaffin cells in the adrenal medulla. Extra-adrenal paragangliomas, also known as extra-adrenal pheochromocytomas, are closely associated but less prevalent tumors that originate in the ganglia of the sympathetic nervous system. These tumors release catecholamines and result in a range of symptoms and indications linked to hyperactivity of the sympathetic nervous system.
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This question is part of the following fields:
- Endocrinology
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Question 29
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A 52-year-old woman arrives at the emergency department complaining of worsening dizziness and weakness in the past few days. She reports experiencing abdominal discomfort, nausea, muscle aches, and weight loss over the last month. To investigate potential underlying causes of her symptoms, you order blood tests. What biochemical abnormalities would you anticipate if the patient is suffering from adrenal insufficiency?
Your Answer: Hyponatraemia and hyperkalaemia
Explanation:If the patient is suffering from adrenal insufficiency, it is likely that she will have hyponatremia and hyperkalemia. Adrenal insufficiency occurs when the adrenal glands do not produce enough hormones, particularly cortisol. This can lead to imbalances in electrolytes, such as sodium and potassium. Hyponatremia refers to low levels of sodium in the blood, while hyperkalemia refers to high levels of potassium in the blood. These abnormalities can cause symptoms such as dizziness, weakness, abdominal discomfort, and muscle aches. Additionally, the patient’s reported weight loss and other symptoms are consistent with adrenal insufficiency.
Further Reading:
Addison’s disease, also known as primary adrenal insufficiency or hypoadrenalism, is a rare disorder caused by the destruction of the adrenal cortex. This leads to reduced production of glucocorticoids, mineralocorticoids, and adrenal androgens. The deficiency of cortisol results in increased production of adrenocorticotropic hormone (ACTH) due to reduced negative feedback to the pituitary gland. This condition can cause metabolic disturbances such as hyperkalemia, hyponatremia, hypercalcemia, and hypoglycemia.
The symptoms of Addison’s disease can vary but commonly include fatigue, weight loss, muscle weakness, and low blood pressure. It is more common in women and typically affects individuals between the ages of 30-50. The most common cause of primary hypoadrenalism in developed countries is autoimmune destruction of the adrenal glands. Other causes include tuberculosis, adrenal metastases, meningococcal septicaemia, HIV, and genetic disorders.
The diagnosis of Addison’s disease is often suspected based on low cortisol levels and electrolyte abnormalities. The adrenocorticotropic hormone stimulation test is commonly used for confirmation. Other investigations may include adrenal autoantibodies, imaging scans, and genetic screening.
Addisonian crisis is a potentially life-threatening condition that occurs when there is an acute deficiency of cortisol and aldosterone. It can be the first presentation of undiagnosed Addison’s disease. Precipitating factors of an Addisonian crisis include infection, dehydration, surgery, trauma, physiological stress, pregnancy, hypoglycemia, and acute withdrawal of long-term steroids. Symptoms of an Addisonian crisis include malaise, fatigue, nausea or vomiting, abdominal pain, fever, muscle pains, dehydration, confusion, and loss of consciousness.
There is no fixed consensus on diagnostic criteria for an Addisonian crisis, as symptoms are non-specific. Investigations may include blood tests, blood gas analysis, and septic screens if infection is suspected. Management involves administering hydrocortisone and fluids. Hydrocortisone is given parenterally, and the dosage varies depending on the age of the patient. Fluid resuscitation with saline is necessary to correct any electrolyte disturbances and maintain blood pressure. The underlying cause of the crisis should also be identified and treated. Close monitoring of sodium levels is important to prevent complications such as osmotic demyelination syndrome.
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This question is part of the following fields:
- Endocrinology
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Question 30
Correct
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A 37 year old woman presents to the emergency department with complaints of headache, profuse sweating, and heart palpitations. Upon examination, her blood pressure is measured at 228/114 mmHg. The possibility of phaeochromocytoma crosses your mind. Where do phaeochromocytomas typically originate within the adrenal tissue?
Your Answer: Medulla
Explanation:Phaeochromocytoma is a rare neuroendocrine tumor that secretes catecholamines. It typically arises from chromaffin tissue in the adrenal medulla, but can also occur in extra-adrenal chromaffin tissue. The majority of cases are spontaneous and occur in individuals aged 40-50 years. However, up to 30% of cases are hereditary and associated with genetic mutations. About 10% of phaeochromocytomas are metastatic, with extra-adrenal tumors more likely to be metastatic.
The clinical features of phaeochromocytoma are a result of excessive catecholamine production. Symptoms are typically paroxysmal and include hypertension, headaches, palpitations, sweating, anxiety, tremor, abdominal and flank pain, and nausea. Catecholamines have various metabolic effects, including glycogenolysis, mobilization of free fatty acids, increased serum lactate, increased metabolic rate, increased myocardial force and rate of contraction, and decreased systemic vascular resistance.
Diagnosis of phaeochromocytoma involves measuring plasma and urine levels of metanephrines, catecholamines, and urine vanillylmandelic acid. Imaging studies such as abdominal CT or MRI are used to determine the location of the tumor. If these fail to find the site, a scan with metaiodobenzylguanidine (MIBG) labeled with radioactive iodine is performed. The highest sensitivity and specificity for diagnosis is achieved with plasma metanephrine assay.
The definitive treatment for phaeochromocytoma is surgery. However, before surgery, the patient must be stabilized with medical management. This typically involves alpha-blockade with medications such as phenoxybenzamine or phentolamine, followed by beta-blockade with medications like propranolol. Alpha blockade is started before beta blockade to allow for expansion of blood volume and to prevent a hypertensive crisis.
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This question is part of the following fields:
- Endocrinology
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