00
Correct
00
Incorrect
00 : 00 : 0 00
Session Time
00 : 00
Average Question Time ( Mins)
  • Question 1 - A 19-year-old man was recently admitted to hospital with invasive meningococcal disease. He...

    Incorrect

    • A 19-year-old man was recently admitted to hospital with invasive meningococcal disease. He has no other medical history but is now complaining of extreme fatigue, light-headedness and rapid weight loss. He has also noticed his skin appears much more tanned than usual. His BP is 98/60 mmHg. Capillary glucose is found to be 2.2 mmol/L.

      Hb 135 g/L Male: (130 - 180)
      Platelets 280 * 109/L (150 - 400)
      WBC 5.5 * 109/L (4.0 - 11.0)
      Na+ 128 mmol/L (135 - 145)
      K+ 5.8 mmol/L (3.5 - 5.0)
      Bicarbonate 19 mmol/L (22 - 29)
      Urea 8.0 mmol/L (2.0 - 7.0)
      Creatinine 125 µmol/L (55 - 120)

      What is the most likely cause of his symptoms?

      Your Answer: Insulinoma

      Correct Answer: Waterhouse-Friedrichsen syndrome

      Explanation:

      Understanding Waterhouse-Friderichsen Syndrome

      Waterhouse-Friderichsen syndrome is a condition that occurs when the adrenal glands fail due to a previous adrenal haemorrhage caused by a severe bacterial infection. The most common cause of this condition is Neisseria meningitidis, but it can also be caused by other bacteria such as Haemophilus influenzae, Pseudomonas aeruginosa, Escherichia coli, and Streptococcus pneumoniae.

      The symptoms of Waterhouse-Friderichsen syndrome are similar to those of hypoadrenalism, including lethargy, weakness, anorexia, nausea and vomiting, and weight loss. Other symptoms may include hyperpigmentation, especially in the palmar creases, vitiligo, and loss of pubic hair in women. In severe cases, a crisis may occur, which can lead to collapse, shock, and pyrexia.

    • This question is part of the following fields:

      • Endocrine System
      236.5
      Seconds
  • Question 2 - A 25-year-old woman has a total thyroidectomy to treat papillary carcinoma of the...

    Correct

    • A 25-year-old woman has a total thyroidectomy to treat papillary carcinoma of the thyroid. During examination of histological sections of the thyroid gland, the pathologist discovers the presence of psammoma bodies. What is the primary composition of these bodies?

      Your Answer: Clusters of calcification

      Explanation:

      Clusters of microcalcification, known as psammoma bodies, are frequently observed in papillary carcinomas.

      Thyroid cancer rarely causes hyperthyroidism or hypothyroidism as it does not usually secrete thyroid hormones. The most common type of thyroid cancer is papillary carcinoma, which is often found in young females and has an excellent prognosis. Follicular carcinoma is less common, while medullary carcinoma is a cancer of the parafollicular cells that secrete calcitonin and is associated with multiple endocrine neoplasia type 2. Anaplastic carcinoma is rare and not responsive to treatment, causing pressure symptoms. Lymphoma is also rare and associated with Hashimoto’s thyroiditis.

      Management of papillary and follicular cancer involves a total thyroidectomy followed by radioiodine to kill residual cells. Yearly thyroglobulin levels are monitored to detect early recurrent disease. Papillary carcinoma usually contains a mixture of papillary and colloidal filled follicles, while follicular adenoma presents as a solitary thyroid nodule and malignancy can only be excluded on formal histological assessment. Follicular carcinoma may appear macroscopically encapsulated, but microscopically capsular invasion is seen. Medullary carcinoma is associated with raised serum calcitonin levels and familial genetic disease in up to 20% of cases. Anaplastic carcinoma is most common in elderly females and is treated by resection where possible, with palliation achieved through isthmusectomy and radiotherapy. Chemotherapy is ineffective.

    • This question is part of the following fields:

      • Endocrine System
      19.2
      Seconds
  • Question 3 - A young man comes to the clinic with symptoms suggestive of mania. After...

    Incorrect

    • A young man comes to the clinic with symptoms suggestive of mania. After further inquiry and assessment, he is found to have tachycardia, sweaty palms, and a recent bout of diarrhea. What is the probable diagnosis?

      Your Answer: Bipolar disorder

      Correct Answer: Grave's disease

      Explanation:

      The correct diagnosis for this patient is Grave’s disease, which is characterized by hyperthyroidism. While mania may be a symptom, it is important to note that tachycardia, sweaty hands, and exophthalmos are specific to Grave’s disease.

      Bipolar disorder may also present with manic episodes, but it does not typically include the other symptoms associated with hyperthyroidism.

      Hashimoto’s thyroiditis is another autoimmune thyroid disorder, but it causes hypothyroidism instead of hyperthyroidism. Symptoms of hypothyroidism may include bradycardia and dry skin.

      Graves’ Disease: Common Features and Unique Signs

      Graves’ disease is the most frequent cause of thyrotoxicosis, which is commonly observed in women aged 30-50 years. The condition presents typical features of thyrotoxicosis, such as weight loss, palpitations, and heat intolerance. However, Graves’ disease also displays specific signs that are not present in other causes of thyrotoxicosis. These include eye signs, such as exophthalmos and ophthalmoplegia, as well as pretibial myxoedema and thyroid acropachy. The latter is a triad of digital clubbing, soft tissue swelling of the hands and feet, and periosteal new bone formation.

      Graves’ disease is characterized by the presence of autoantibodies, including TSH receptor stimulating antibodies in 90% of patients and anti-thyroid peroxidase antibodies in 75% of patients. Thyroid scintigraphy reveals a diffuse, homogenous, and increased uptake of radioactive iodine. These features help distinguish Graves’ disease from other causes of thyrotoxicosis and aid in its diagnosis.

    • This question is part of the following fields:

      • Endocrine System
      15.4
      Seconds
  • Question 4 - A 68-year-old man with a long history of poorly controlled type-2 diabetes is...

    Incorrect

    • A 68-year-old man with a long history of poorly controlled type-2 diabetes is prescribed a new medication that increases urinary glucose excretion. The doctor informs him that it belongs to the SGLT-2 inhibitor drug class.

      Which of the following medications is classified as an SGLT-2 inhibitor?

      Your Answer: Linagliptin

      Correct Answer: Dapagliflozin

      Explanation:

      SGLT2 inhibitors are known as gliflozins.

      Sulfonylurea refers to tolbutamide.

      GLP-1 receptor agonist is exenatide.

      DPP-4 inhibitor is linagliptin.

      Understanding SGLT-2 Inhibitors

      SGLT-2 inhibitors are medications that work by blocking the reabsorption of glucose in the kidneys, leading to increased excretion of glucose in the urine. This mechanism of action helps to lower blood sugar levels in patients with type 2 diabetes mellitus. Examples of SGLT-2 inhibitors include canagliflozin, dapagliflozin, and empagliflozin.

      However, it is important to note that SGLT-2 inhibitors can also have adverse effects. Patients taking these medications may be at increased risk for urinary and genital infections due to the increased glucose in the urine. Fournier’s gangrene, a rare but serious bacterial infection of the genital area, has also been reported. Additionally, there is a risk of normoglycemic ketoacidosis, a condition where the body produces high levels of ketones even when blood sugar levels are normal. Finally, patients taking SGLT-2 inhibitors may be at increased risk for lower-limb amputations, so it is important to closely monitor the feet.

      Despite these potential risks, SGLT-2 inhibitors can also have benefits. Patients taking these medications often experience weight loss, which can be beneficial for those with type 2 diabetes mellitus. Overall, it is important for patients to discuss the potential risks and benefits of SGLT-2 inhibitors with their healthcare provider before starting treatment.

    • This question is part of the following fields:

      • Endocrine System
      60.5
      Seconds
  • Question 5 - A 55-year-old man comes in for his regular check-up with his GP. He...

    Incorrect

    • A 55-year-old man comes in for his regular check-up with his GP. He has a medical history of chronic pancreatitis and diabetes mellitus and is currently taking the maximum doses of metformin and gliclazide. During a random plasma glucose test, his levels show 18.0 mmol/l and his urinalysis reveals glycosuria with minimal ketones. The GP suspects that his body is not producing enough insulin and decides to initiate insulin therapy. Can you identify the location in the body where insulin is produced?

      Your Answer: Gastric G cells

      Correct Answer: Pancreatic beta cells

      Explanation:

      Diabetes mellitus in this patient is most likely caused by chronic pancreatitis, which has resulted in the destruction of the pancreatic endocrine cells responsible for producing endogenous insulin. These cells are located in the Islets of Langerhans and are known as pancreatic beta cells (β-cells). Other cells in the pancreas, such as alpha cells (which secrete glucagon) and delta cells (which secrete somatostatin), do not produce insulin. Similarly, gastric G cells secrete gastrin and are not involved in insulin production.

      Insulin is a hormone produced by the pancreas that plays a crucial role in regulating the metabolism of carbohydrates and fats in the body. It works by causing cells in the liver, muscles, and fat tissue to absorb glucose from the bloodstream, which is then stored as glycogen in the liver and muscles or as triglycerides in fat cells. The human insulin protein is made up of 51 amino acids and is a dimer of an A-chain and a B-chain linked together by disulfide bonds. Pro-insulin is first formed in the rough endoplasmic reticulum of pancreatic beta cells and then cleaved to form insulin and C-peptide. Insulin is stored in secretory granules and released in response to high levels of glucose in the blood. In addition to its role in glucose metabolism, insulin also inhibits lipolysis, reduces muscle protein loss, and increases cellular uptake of potassium through stimulation of the Na+/K+ ATPase pump.

    • This question is part of the following fields:

      • Endocrine System
      70
      Seconds
  • Question 6 - A 65-year-old man with type 2 diabetes mellitus has been taking metformin 1g...

    Incorrect

    • A 65-year-old man with type 2 diabetes mellitus has been taking metformin 1g twice daily for the past 6 months. Despite this, his HbA1c has remained above target at 64 mmol/mol (8.0%).

      He has a history of left ventricular failure following a myocardial infarction 2 years ago. He has been trying to lose weight since but still has a body mass index of 33 kg/m². He is also prone to recurrent urinary tract infections.

      You intend to intensify treatment by adding a second medication.

      What is the mechanism of action of the most appropriate anti-diabetic drug for him?

      Your Answer: Activation of peroxisome proliferator-activated gamma receptors to increase insulin sensitivity

      Correct Answer: Inhibition of dipeptidyl peptidase-4 (DPP-4) to increase incretin levels

      Explanation:

      Diabetes mellitus is a condition that has seen the development of several drugs in recent years. One hormone that has been the focus of much research is glucagon-like peptide-1 (GLP-1), which is released by the small intestine in response to an oral glucose load. In type 2 diabetes mellitus (T2DM), insulin resistance and insufficient B-cell compensation occur, and the incretin effect, which is largely mediated by GLP-1, is decreased. GLP-1 mimetics, such as exenatide and liraglutide, increase insulin secretion and inhibit glucagon secretion, resulting in weight loss, unlike other medications. They are sometimes used in combination with insulin in T2DM to minimize weight gain. Dipeptidyl peptidase-4 (DPP-4) inhibitors, such as vildagliptin and sitagliptin, increase levels of incretins by decreasing their peripheral breakdown, are taken orally, and do not cause weight gain. Nausea and vomiting are the major adverse effects of GLP-1 mimetics, and the Medicines and Healthcare products Regulatory Agency has issued specific warnings on the use of exenatide, reporting that it has been linked to severe pancreatitis in some patients. NICE guidelines suggest that a DPP-4 inhibitor might be preferable to a thiazolidinedione if further weight gain would cause significant problems, a thiazolidinedione is contraindicated, or the person has had a poor response to a thiazolidinedione.

    • This question is part of the following fields:

      • Endocrine System
      202.2
      Seconds
  • Question 7 - A 45-year-old male is recovering from trans-sphenoidal surgery for a non-functioning pituitary adenoma....

    Correct

    • A 45-year-old male is recovering from trans-sphenoidal surgery for a non-functioning pituitary adenoma. He reports excessive thirst and increased water intake to the doctors during the ward round, four days after the surgery. The patient's fluid chart shows a urine output of 7 litres in the past 24 hours, and his blood glucose level is 5.2mmol/L. To confirm the diagnosis, the doctors plan to conduct a water-deprivation test and a vasopressin test.

      What are the expected results of the urine osmolality investigations, given the likely diagnosis?

      Your Answer: After fluid deprivation, low; after desmopressin, high

      Explanation:

      The patient has developed cranial diabetes insipidus after pituitary surgery. Water deprivation testing showed low urine osmolality after fluid deprivation and high urine osmolality after desmopressin administration. This condition can also be caused by head trauma or occur idiopathically. Water deprivation testing can also be useful for investigating psychogenic polydipsia. Nephrogenic diabetes insipidus is the other main cause, where the kidneys cannot properly respond to vasopressin.

      The water deprivation test is a diagnostic tool used to assess patients with polydipsia, or excessive thirst. During the test, the patient is instructed to refrain from drinking water, and their bladder is emptied. Hourly measurements of urine and plasma osmolalities are taken to monitor changes in the body’s fluid balance. The results of the test can help identify the underlying cause of the patient’s polydipsia. Normal results show a high urine osmolality after the administration of DDAVP, while psychogenic polydipsia is characterized by a low urine osmolality. Cranial DI and nephrogenic DI are both associated with high plasma osmolalities and low urine osmolalities.

    • This question is part of the following fields:

      • Endocrine System
      525.7
      Seconds
  • Question 8 - A 42-year-old woman complains of fatigue after experiencing flu-like symptoms two weeks ago....

    Incorrect

    • A 42-year-old woman complains of fatigue after experiencing flu-like symptoms two weeks ago. Upon examination, she has a smooth, small goiter and a pulse rate of 68 bpm. Her lab results show a Free T4 level of 9.3 pmol/L (normal range: 9.8-23.1) and a TSH level of 49.3 mU/L (normal range: 0.35-5.50). What additional test would you perform to confirm the diagnosis?

      Your Answer: Thyroid ultrasound

      Correct Answer: Thyroid peroxidase (TPO) antibodies

      Explanation:

      Diagnosis and Management of Primary Hypothyroidism

      The patient’s test results indicate a case of primary hypothyroidism, characterized by low levels of thyroxine (T4) and elevated thyroid-stimulating hormone (TSH). The most likely cause of this condition is Hashimoto’s thyroiditis, which is often accompanied by the presence of thyroid peroxidase antibodies. While the patient has a goitre, it appears to be smooth and non-threatening, so a thyroid ultrasound is not necessary. Additionally, a radio-iodine uptake scan is unlikely to show significant uptake and is therefore not recommended. Positive TSH receptor antibodies are typically associated with Graves’ disease, which is not the likely diagnosis in this case. For further information on Hashimoto’s thyroiditis, patients can refer to Patient.info.

    • This question is part of the following fields:

      • Endocrine System
      27.7
      Seconds
  • Question 9 - A 60-year-old male presents with increasing fatigue.

    Three months ago, he was diagnosed...

    Incorrect

    • A 60-year-old male presents with increasing fatigue.

      Three months ago, he was diagnosed with bronchial carcinoma and has undergone chemotherapy. Upon admission, his electrolyte levels were measured as follows:

      - Sodium: 118 mmol/L (137-144)
      - Potassium: 3.5 mmol/L (3.5-4.9)
      - Urea: 3.2 mmol/L (2.5-7.5)
      - Creatinine: 65 µmol/L (60-110)

      What would be the most appropriate initial investigation for this patient?

      Your Answer: Serum ADH concentration

      Correct Answer: Urine osmolality and sodium concentration

      Explanation:

      Hyponatraemia in Bronchial Carcinoma Patients

      Hyponatraemia is a common condition in patients with bronchial carcinoma. It is characterized by a marked decrease in sodium levels, which appears to be dilutional based on other test results that fall within the lower end of the normal range. The most likely cause of this condition is the syndrome of inappropriate ADH secretion (SIADH), which occurs when the tumour produces ADH in an ectopic manner. However, the diagnosis of SIADH is one of exclusion, and other possibilities such as hypoadrenalism due to metastatic disease to the adrenals should also be considered.

      To determine the cause of hyponatraemia, initial tests such as urine sodium and osmolality are recommended. These tests can help rule out other possible causes and confirm the diagnosis of SIADH. Treatment for this condition typically involves fluid restriction. It is important to note that measuring ADH concentrations is not a reliable diagnostic tool as it is not widely available and does not provide any useful information.

      In summary, hyponatraemia is a common condition in bronchial carcinoma patients, and SIADH is the most likely cause. Initial tests such as urine sodium and osmolality can help confirm the diagnosis, and treatment involves fluid restriction.

    • This question is part of the following fields:

      • Endocrine System
      50.5
      Seconds
  • Question 10 - Sarah is a 19-year-old female with type 1 diabetes. After dinner, she goes...

    Incorrect

    • Sarah is a 19-year-old female with type 1 diabetes. After dinner, she goes out for the night and drinks 15 units of alcohol. She has taken her insulin according to her carbohydrate counting. However, in the early morning, her friend finds it difficult to wake her up and she is hospitalized due to hypoglycemia. How did her alcohol consumption play a role in this?

      Your Answer: Alcohol increases glucose uptake in the brain

      Correct Answer: Alcohol inhibits glycogenolysis

      Explanation:

      Alcoholic drinks contain carbohydrates that can cause an increase in blood glucose levels. However, the consumption of alcohol can also inhibit glycogenolysis, leading to a delayed hypoglycemia, particularly during the night. This can result in neuroglycopenia, which may impair one’s level of consciousness.

      Understanding Diabetes Mellitus: A Basic Overview

      Diabetes mellitus is a chronic condition characterized by abnormally raised levels of blood glucose. It is one of the most common conditions encountered in clinical practice and represents a significant burden on the health systems of the developed world. The management of diabetes mellitus is crucial as untreated type 1 diabetes would usually result in death. Poorly treated type 1 diabetes mellitus can still result in significant morbidity and mortality. The main focus of diabetes management now is reducing the incidence of macrovascular and microvascular complications.

      There are different types of diabetes mellitus, including type 1 diabetes mellitus, type 2 diabetes mellitus, prediabetes, gestational diabetes, maturity onset diabetes of the young, latent autoimmune diabetes of adults, and other types. The presentation of diabetes mellitus depends on the type, with type 1 diabetes mellitus often presenting with weight loss, polydipsia, polyuria, and diabetic ketoacidosis. On the other hand, type 2 diabetes mellitus is often picked up incidentally on routine blood tests and presents with polydipsia and polyuria.

      There are four main ways to check blood glucose, including a finger-prick bedside glucose monitor, a one-off blood glucose, a HbA1c, and a glucose tolerance test. The diagnostic criteria are determined by WHO, with a fasting glucose greater than or equal to 7.0 mmol/l and random glucose greater than or equal to 11.1 mmol/l being diagnostic of diabetes mellitus. Management of diabetes mellitus involves drug therapy to normalize blood glucose levels, monitoring for and treating any complications related to diabetes, and modifying any other risk factors for other conditions such as cardiovascular disease. The first-line drug for the vast majority of patients with type 2 diabetes mellitus is metformin, with second-line drugs including sulfonylureas, gliptins, and pioglitazone. Insulin is used if oral medication is not controlling the blood glucose to a sufficient degree.

    • This question is part of the following fields:

      • Endocrine System
      17.2
      Seconds
  • Question 11 - A 42-year-old woman visits her GP complaining of chest pain. She has a...

    Incorrect

    • A 42-year-old woman visits her GP complaining of chest pain. She has a history of hypertension and is currently taking metformin for diabetes. The GP observes that her BMI is 45. What is a possible complication of the metabolic syndrome in this case?

      Your Answer: Rheumatoid arthritis

      Correct Answer: Ischemic stroke

      Explanation:

      Metabolic syndrome is a group of risk factors for cardiovascular disease that are caused by insulin resistance and central obesity.

      Obesity is associated with higher rates of illness and death, as well as decreased productivity and functioning, increased healthcare expenses, and social and economic discrimination.

      The consequences of obesity include strokes, type 2 diabetes, heart disease, certain cancers (such as breast, colon, and endometrial), polycystic ovarian syndrome, obstructive sleep apnea, fatty liver, gallstones, and mental health issues.

      The Physiology of Obesity: Leptin and Ghrelin

      Leptin is a hormone produced by adipose tissue that plays a crucial role in regulating body weight. It acts on the hypothalamus, specifically on the satiety centers, to decrease appetite and induce feelings of fullness. In cases of obesity, where there is an excess of adipose tissue, leptin levels are high. Leptin also stimulates the release of melanocyte-stimulating hormone (MSH) and corticotrophin-releasing hormone (CRH), which further contribute to the regulation of appetite. On the other hand, low levels of leptin stimulate the release of neuropeptide Y (NPY), which increases appetite.

      Ghrelin, on the other hand, is a hormone that stimulates hunger. It is mainly produced by the P/D1 cells lining the fundus of the stomach and epsilon cells of the pancreas. Ghrelin levels increase before meals, signaling the body to prepare for food intake, and decrease after meals, indicating that the body has received enough nutrients.

      In summary, the balance between leptin and ghrelin plays a crucial role in regulating appetite and body weight. In cases of obesity, there is an imbalance in this system, with high levels of leptin and potentially disrupted ghrelin signaling, leading to increased appetite and weight gain.

    • This question is part of the following fields:

      • Endocrine System
      45.8
      Seconds
  • Question 12 - A 65-year-old man presents to the Emergency Department with confusion, drowsiness, and nausea...

    Incorrect

    • A 65-year-old man presents to the Emergency Department with confusion, drowsiness, and nausea accompanied by vomiting. His daughter reports that he has been feeling fatigued and unwell with a persistent cough, and he has been smoking 20 cigarettes per day for 45 years. The patient is unable to provide a complete medical history due to his confusion, but he mentions that he sometimes coughs up blood and his urine has been darker than usual. On examination, he appears to be short of breath but euvolaemic. Blood tests reveal low serum sodium, high urinary sodium, low plasma osmolality, and high urinary osmolality. Renal and thyroid function tests are normal. A chest x-ray shows a lung carcinoma, leading you to suspect that this presentation may be caused by a syndrome of inappropriate antidiuretic hormone secretion.

      What is the underlying mechanism responsible for the hyponatraemia?

      Your Answer: Insertion of aquaporin-1 channels

      Correct Answer: Insertion of aquaporin-2 channels

      Explanation:

      The insertion of aquaporin-2 channels is promoted by antidiuretic hormone, which facilitates water reabsorption. However, in the case of syndrome of inappropriate antidiuretic hormone secretion (SiADH), which is caused by small cell lung cancer, the normal negative feedback loop fails, resulting in the continuous production of ADH even when serum osmolality returns to normal. This leads to euvolemic hyponatremia, where the body retains water but continues to lose sodium, resulting in concentrated urine. The underlying mechanism of this condition is the persistent increase in the number of aquaporin-2 channels, which promotes water reabsorption, rather than any effect on sodium transport mechanisms.

      Understanding Antidiuretic Hormone (ADH)

      Antidiuretic hormone (ADH) is a hormone that is produced in the supraoptic nuclei of the hypothalamus and released by the posterior pituitary gland. Its primary function is to conserve body water by promoting water reabsorption in the collecting ducts of the kidneys through the insertion of aquaporin-2 channels.

      ADH secretion is regulated by various factors. An increase in extracellular fluid osmolality, a decrease in volume or pressure, and the presence of angiotensin II can all increase ADH secretion. Conversely, a decrease in extracellular fluid osmolality, an increase in volume, a decrease in temperature, or the absence of ADH can decrease its secretion.

      Diabetes insipidus (DI) is a condition that occurs when there is either a deficiency of ADH (cranial DI) or an insensitivity to ADH (nephrogenic DI). Cranial DI can be treated with desmopressin, which is an analog of ADH.

      Overall, understanding the role of ADH in regulating water balance in the body is crucial for maintaining proper hydration and preventing conditions like DI.

    • This question is part of the following fields:

      • Endocrine System
      62.7
      Seconds
  • Question 13 - A 53-year-old male presents to an endocrinology clinic with recurring symptoms of painful...

    Incorrect

    • A 53-year-old male presents to an endocrinology clinic with recurring symptoms of painful fingers and hands that seem to be enlarging. He was previously diagnosed with acromegaly eight months ago and underwent transsphenoidal surgery six months ago to remove the pituitary adenoma responsible. During examination, his facial features appear rough, and his hands are large and spade-like. You opt to manage this patient's symptoms with medication and initiate a trial of octreotide.

      What physiological function is linked to this medication?

      Your Answer: Stimulation of aldosterone secretion from the adrenal cortex

      Correct Answer: Inhibition of glucagon secretion from the pancreas

      Explanation:

      Somatostatin analogues, such as octreotide, are used to treat acromegaly in patients who have not responded well to surgery. Somatostatin is a hormone that has various functions, including inhibiting the secretion of growth hormone from the anterior pituitary gland and insulin and glucagon from the pancreas. Therefore, the correct answer is that somatostatin inhibits the secretion of glucagon.

      The secretion of ACTH by the pancreas is regulated by a negative feedback loop involving cortisol and corticotropin-releasing hormone (CRH). When blood cortisol levels decrease, CRH is secreted from the hypothalamus, which then stimulates the secretion of ACTH from the anterior pituitary gland.

      Somatostatin analogues typically do not affect the secretion of aldosterone from the pancreas, which is primarily stimulated by angiotensin-II.

      Somatostatin analogues inhibit the secretion of growth hormone from the anterior pituitary gland. The hormone responsible for stimulating the secretion of growth hormone is growth hormone-releasing hormone (GHRH).

      The secretion of insulin by pancreatic β-cells is inhibited by somatostatin analogues. The primary stimulus for insulin secretion is low blood glucose levels, but other substances such as arginine and leucine, acetylcholine, sulfonylurea, cholecystokinin, and incretins can also stimulate insulin release.

      Somatostatin: The Inhibitor Hormone

      Somatostatin, also known as growth hormone inhibiting hormone (GHIH), is a hormone produced by delta cells found in the pancreas, pylorus, and duodenum. Its main function is to inhibit the secretion of growth hormone, insulin, and glucagon. It also decreases acid and pepsin secretion, as well as pancreatic enzyme secretion. Additionally, somatostatin inhibits the trophic effects of gastrin and stimulates gastric mucous production.

      Somatostatin analogs are commonly used in the management of acromegaly, a condition characterized by excessive growth hormone secretion. These analogs work by inhibiting growth hormone secretion, thereby reducing the symptoms associated with acromegaly.

      The secretion of somatostatin is regulated by various factors. Its secretion increases in response to fat, bile salts, and glucose in the intestinal lumen, as well as glucagon. On the other hand, insulin decreases the secretion of somatostatin.

      In summary, somatostatin plays a crucial role in regulating the secretion of various hormones and enzymes in the body. Its inhibitory effects on growth hormone, insulin, and glucagon make it an important hormone in the management of certain medical conditions.

    • This question is part of the following fields:

      • Endocrine System
      25.9
      Seconds
  • Question 14 - A 7-year-old boy is brought to the doctor by his father with a...

    Incorrect

    • A 7-year-old boy is brought to the doctor by his father with a complaint of frequent urination and excessive thirst. Upon conducting a fasting blood glucose test, the results are found to be abnormally high. The doctor suspects type 1 diabetes and initiates first-line injectable therapy.

      What characteristic of this medication should be noted?

      Your Answer: Decreases cellular uptake of potassium

      Correct Answer: Decreases serum potassium

      Explanation:

      Insulin stimulates the Na+/K+ ATPase pump, which leads to a decrease in serum potassium levels. This is the primary treatment for type 1 diabetes, where the pancreas no longer produces insulin, causing high blood sugar levels. Injectable insulin allows glucose to enter cells, and insulin also increases cellular uptake of potassium while decreasing serum potassium levels. Insulin also stimulates muscle protein synthesis, reducing muscle protein loss. Insulin is secreted in response to hyperglycaemia, where high blood sugar levels trigger the beta cells of the pancreas to release insulin in healthy individuals.

      Insulin is a hormone produced by the pancreas that plays a crucial role in regulating the metabolism of carbohydrates and fats in the body. It works by causing cells in the liver, muscles, and fat tissue to absorb glucose from the bloodstream, which is then stored as glycogen in the liver and muscles or as triglycerides in fat cells. The human insulin protein is made up of 51 amino acids and is a dimer of an A-chain and a B-chain linked together by disulfide bonds. Pro-insulin is first formed in the rough endoplasmic reticulum of pancreatic beta cells and then cleaved to form insulin and C-peptide. Insulin is stored in secretory granules and released in response to high levels of glucose in the blood. In addition to its role in glucose metabolism, insulin also inhibits lipolysis, reduces muscle protein loss, and increases cellular uptake of potassium through stimulation of the Na+/K+ ATPase pump.

    • This question is part of the following fields:

      • Endocrine System
      8.8
      Seconds
  • Question 15 - Which one of the following does not trigger insulin secretion? ...

    Correct

    • Which one of the following does not trigger insulin secretion?

      Your Answer: Atenolol

      Explanation:

      The release of insulin is prevented by beta blockers.

      Factors that trigger insulin release include glucose, amino acids, vagal cholinergic stimulation, secretin/gastrin/CCK, fatty acids, and beta adrenergic drugs.

      Insulin is a hormone produced by the pancreas that plays a crucial role in regulating the metabolism of carbohydrates and fats in the body. It works by causing cells in the liver, muscles, and fat tissue to absorb glucose from the bloodstream, which is then stored as glycogen in the liver and muscles or as triglycerides in fat cells. The human insulin protein is made up of 51 amino acids and is a dimer of an A-chain and a B-chain linked together by disulfide bonds. Pro-insulin is first formed in the rough endoplasmic reticulum of pancreatic beta cells and then cleaved to form insulin and C-peptide. Insulin is stored in secretory granules and released in response to high levels of glucose in the blood. In addition to its role in glucose metabolism, insulin also inhibits lipolysis, reduces muscle protein loss, and increases cellular uptake of potassium through stimulation of the Na+/K+ ATPase pump.

    • This question is part of the following fields:

      • Endocrine System
      161.1
      Seconds
  • Question 16 - A 55-year-old woman comes to her doctor complaining of fatigue, difficulty passing stool,...

    Correct

    • A 55-year-old woman comes to her doctor complaining of fatigue, difficulty passing stool, and muscle weakness. Her lab results show:

      Free T4 6 pmol/l (9-18 pmol/l)
      TSH 7.2 mu/l (0.5-5.5 mu/l)

      Based on the probable diagnosis, which of the following tests is most likely to be positive in this patient?

      Your Answer: Anti-thyroid peroxidase (anti-TPO) antibodies

      Explanation:

      Rheumatoid factor is not the most suitable answer for a patient with hypothyroidism, despite its presence in various rheumatological conditions and healthy individuals.

      Understanding Thyroid Autoantibodies

      Thyroid autoantibodies are antibodies that attack the thyroid gland, causing various thyroid disorders. There are three main types of anti-thyroid autoantibodies: anti-thyroid peroxidase (anti-TPO) antibodies, TSH receptor antibodies, and thyroglobulin antibodies. Anti-TPO antibodies are present in 90% of Hashimoto’s thyroiditis cases and 75% of Graves’ disease cases. TSH receptor antibodies are found in 90-100% of Graves’ disease cases. Thyroglobulin antibodies are present in 70% of Hashimoto’s thyroiditis cases, 30% of Graves’ disease cases, and a small proportion of thyroid cancer cases.

      Understanding the different types of thyroid autoantibodies is important in diagnosing and treating thyroid disorders. Hashimoto’s thyroiditis and Graves’ disease are the most common autoimmune thyroid disorders, and the presence of specific autoantibodies can help differentiate between the two. Additionally, monitoring the levels of these antibodies can help track the progression of the disease and the effectiveness of treatment. Overall, understanding thyroid autoantibodies is crucial in managing thyroid health.

    • This question is part of the following fields:

      • Endocrine System
      124.1
      Seconds
  • Question 17 - A 60-year-old patient visits their doctor complaining of dehydration caused by vomiting and...

    Incorrect

    • A 60-year-old patient visits their doctor complaining of dehydration caused by vomiting and diarrhoea. The kidneys detect reduced renal perfusion, leading to activation of the renin-angiotensin-aldosterone system. What is the specific part of the adrenal gland required for this system?

      Your Answer: Zona reticularis

      Correct Answer: Zona glomerulosa

      Explanation:

      Aldosterone is produced in the zona glomerulosa of the adrenal gland.

      Renin is released by juxtaglomerular cells located in the nephron.

      ACE is produced by the pulmonary endothelium in the lungs.

      The adrenal gland is composed of the zona glomerulosa, fasciculata, and reticularis.

      Glucocorticoids are produced in the zona fasciculata.

      Adrenal Physiology: Medulla and Cortex

      The adrenal gland is composed of two main parts: the medulla and the cortex. The medulla is responsible for secreting the catecholamines noradrenaline and adrenaline, which are released in response to sympathetic nervous system stimulation. The chromaffin cells of the medulla are innervated by the splanchnic nerves, and the release of these hormones is triggered by the secretion of acetylcholine from preganglionic sympathetic fibers. Phaeochromocytomas, which are tumors derived from chromaffin cells, can cause excessive secretion of both adrenaline and noradrenaline.

      The adrenal cortex is divided into three distinct zones: the zona glomerulosa, zona fasciculata, and zona reticularis. Each zone is responsible for secreting different hormones. The outer zone, zona glomerulosa, secretes aldosterone, which regulates electrolyte balance and blood pressure. The middle zone, zona fasciculata, secretes glucocorticoids, which are involved in the regulation of metabolism, immune function, and stress response. The inner zone, zona reticularis, secretes androgens, which are involved in the development and maintenance of male sex characteristics.

      Most of the hormones secreted by the adrenal cortex, including glucocorticoids and aldosterone, are bound to plasma proteins in the circulation. Glucocorticoids are inactivated and excreted by the liver. Understanding the physiology of the adrenal gland is important for the diagnosis and treatment of various endocrine disorders.

    • This question is part of the following fields:

      • Endocrine System
      48.2
      Seconds
  • Question 18 - A 29-year-old woman presents to her GP complaining of a tingling sensation around...

    Incorrect

    • A 29-year-old woman presents to her GP complaining of a tingling sensation around her mouth and intermittent cramps in her legs. Trousseau's sign is positive. Blood results are shown below.

      Urea 4.0 mmol/L (2.0 - 7.0)
      Creatinine 80 µmol/L (55 - 120)
      Calcium 1.95 mmol/L (2.1-2.6)
      Phosphate 1.2 mmol/L (0.8-1.4)
      Vitamin D 150 nmol/L (50-250)
      Parathyroid hormone (PTH) 1.7 pmol/L (1.6-8.5)

      Derangement of what substance may be responsible for this patient's presentation?

      Your Answer: Amylase

      Correct Answer: Magnesium

      Explanation:

      The correct answer is magnesium. Adequate levels of magnesium are necessary for the proper functioning of parathyroid hormone, which can lead to hypocalcemia if magnesium levels are low. Magnesium is also essential for PTH secretion and sensitivity. Amylase, chloride, and potassium are not associated with hypocalcemia. While severe pancreatitis may cause hypocalcemia, it is typically accompanied by other symptoms such as vomiting and epigastric pain. Chloride is not linked to hypocalcemia, and hypomagnesemia can cause hypokalemia, which can lead to muscle weakness, tremors, and arrhythmias, as well as ECG changes such as flattened T waves, prolonged PR and QT intervals, and U waves.

      Understanding Parathyroid Hormone and Its Effects

      Parathyroid hormone is a hormone produced by the chief cells of the parathyroid glands. Its main function is to increase the concentration of calcium in the blood by stimulating the PTH receptors in the kidney and bone. This hormone has a short half-life of only 4 minutes.

      The effects of parathyroid hormone are mainly seen in the bone, kidney, and intestine. In the bone, PTH binds to osteoblasts, which then signal to osteoclasts to resorb bone and release calcium. In the kidney, PTH promotes the active reabsorption of calcium and magnesium from the distal convoluted tubule, while decreasing the reabsorption of phosphate. In the intestine, PTH indirectly increases calcium absorption by increasing the activation of vitamin D, which in turn increases calcium absorption.

      Overall, understanding the role of parathyroid hormone is important in maintaining proper calcium levels in the body. Any imbalances in PTH secretion can lead to various disorders such as hyperparathyroidism or hypoparathyroidism.

    • This question is part of the following fields:

      • Endocrine System
      25.9
      Seconds
  • Question 19 - A 32-year-old woman comes to the clinic complaining of fatigue and weight loss...

    Incorrect

    • A 32-year-old woman comes to the clinic complaining of fatigue and weight loss that has been going on for 6 weeks. She reports feeling dizzy when she stands up and has noticed a tan all over her body, despite it being early spring in the UK.

      Upon conducting a blood test, it is found that she has hyponatraemia and hyperkalaemia, with normal full blood count results. A lying-standing blood pressure reading shows a postural drop of 36 mmHg.

      What is the most likely cause of this woman's presentation in the UK, given her symptoms and test results?

      Your Answer: Tuberculosis

      Correct Answer: Autoimmune adrenal insufficiency

      Explanation:

      The most likely cause of this patient’s symptoms is autoimmune adrenalitis, which is responsible for the majority of cases of hypoadrenalism. In this condition, auto-antibodies attack the adrenal gland, leading to a decrease or complete loss of cortisol and aldosterone production. This results in low blood pressure, electrolyte imbalances, and a significant drop in blood pressure upon standing. The body compensates for the low cortisol levels by producing more adrenocorticotropic hormone (ACTH), which can cause the skin to take on a bronze hue.

      While iodine deficiency is a common cause of hypothyroidism worldwide, it is not consistent with this patient’s presentation. A mutation in the HFE gene can lead to haemochromatosis, which can cause reduced libido and skin darkening, but it does not match the electrolyte abnormalities described. Pituitary tumors and tuberculosis can also cause hypoadrenalism, but they are less common in the UK compared to autoimmune causes.

      Addison’s disease is the most common cause of primary hypoadrenalism in the UK, with autoimmune destruction of the adrenal glands being the main culprit, accounting for 80% of cases. This results in reduced production of cortisol and aldosterone. Symptoms of Addison’s disease include lethargy, weakness, anorexia, nausea and vomiting, weight loss, and salt-craving. Hyperpigmentation, especially in palmar creases, vitiligo, loss of pubic hair in women, hypotension, hypoglycemia, and hyponatremia and hyperkalemia may also be observed. In severe cases, a crisis may occur, leading to collapse, shock, and pyrexia.

      Other primary causes of hypoadrenalism include tuberculosis, metastases (such as bronchial carcinoma), meningococcal septicaemia (Waterhouse-Friderichsen syndrome), HIV, and antiphospholipid syndrome. Secondary causes include pituitary disorders, such as tumours, irradiation, and infiltration. Exogenous glucocorticoid therapy can also lead to hypoadrenalism.

      It is important to note that primary Addison’s disease is associated with hyperpigmentation, while secondary adrenal insufficiency is not.

    • This question is part of the following fields:

      • Endocrine System
      19.3
      Seconds
  • Question 20 - A 45-year-old male has been diagnosed with Cushing's disease due to a pituitary...

    Incorrect

    • A 45-year-old male has been diagnosed with Cushing's disease due to a pituitary adenoma, resulting in elevated plasma cortisol levels. Which part of the adrenal gland is responsible for producing cortisol hormone?

      Your Answer: Medulla

      Correct Answer: Zona fasciculata

      Explanation:

      The adrenal gland comprises two primary parts: the cortex and medulla.

      The adrenal medulla is accountable for the production of adrenaline and noradrenaline, which are catecholamines.

      The adrenal cortex is divided into three layers: glomerulosa, fasciculata, and reticularis. The glomerulosa primarily produces mineralocorticoids, while the reticularis mainly produces sex steroids. As a result, the Zona fasciculata is the primary source of glucocorticosteroids.

      Cortisol: Functions and Regulation

      Cortisol is a hormone produced in the zona fasciculata of the adrenal cortex. It plays a crucial role in various bodily functions and is essential for life. Cortisol increases blood pressure by up-regulating alpha-1 receptors on arterioles, allowing for a normal response to angiotensin II and catecholamines. However, it inhibits bone formation by decreasing osteoblasts, type 1 collagen, and absorption of calcium from the gut, while increasing osteoclastic activity. Cortisol also increases insulin resistance and metabolism by increasing gluconeogenesis, lipolysis, and proteolysis. It inhibits inflammatory and immune responses, but maintains the function of skeletal and cardiac muscle.

      The regulation of cortisol secretion is controlled by the hypothalamic-pituitary-adrenal (HPA) axis. The pituitary gland secretes adrenocorticotropic hormone (ACTH), which stimulates the adrenal cortex to produce cortisol. The hypothalamus releases corticotrophin-releasing hormone (CRH), which stimulates the pituitary gland to release ACTH. Stress can also increase cortisol secretion.

      Excess cortisol in the body can lead to Cushing’s syndrome, which can cause a range of symptoms such as weight gain, muscle weakness, and high blood pressure. Understanding the functions and regulation of cortisol is important for maintaining overall health and preventing hormonal imbalances.

    • This question is part of the following fields:

      • Endocrine System
      19.3
      Seconds
  • Question 21 - A 50-year-old woman with thyroid cancer undergoes a total thyroidectomy. The histology report...

    Incorrect

    • A 50-year-old woman with thyroid cancer undergoes a total thyroidectomy. The histology report reveals a diagnosis of medullary thyroid cancer. What test would be most useful for screening for disease recurrence?

      Your Answer: Serum CA 19-9 Levels

      Correct Answer: Serum calcitonin levels

      Explanation:

      The detection of sub clinical recurrence can be facilitated by monitoring the serum levels of calcitonin, which is often secreted by medullary thyroid cancers.

      Thyroid cancer rarely causes hyperthyroidism or hypothyroidism as it does not usually secrete thyroid hormones. The most common type of thyroid cancer is papillary carcinoma, which is often found in young females and has an excellent prognosis. Follicular carcinoma is less common, while medullary carcinoma is a cancer of the parafollicular cells that secrete calcitonin and is associated with multiple endocrine neoplasia type 2. Anaplastic carcinoma is rare and not responsive to treatment, causing pressure symptoms. Lymphoma is also rare and associated with Hashimoto’s thyroiditis.

      Management of papillary and follicular cancer involves a total thyroidectomy followed by radioiodine to kill residual cells. Yearly thyroglobulin levels are monitored to detect early recurrent disease. Papillary carcinoma usually contains a mixture of papillary and colloidal filled follicles, while follicular adenoma presents as a solitary thyroid nodule and malignancy can only be excluded on formal histological assessment. Follicular carcinoma may appear macroscopically encapsulated, but microscopically capsular invasion is seen. Medullary carcinoma is associated with raised serum calcitonin levels and familial genetic disease in up to 20% of cases. Anaplastic carcinoma is most common in elderly females and is treated by resection where possible, with palliation achieved through isthmusectomy and radiotherapy. Chemotherapy is ineffective.

    • This question is part of the following fields:

      • Endocrine System
      12.4
      Seconds
  • Question 22 - A 25-year-old regular gym attendee has been using growth hormone injections to enhance...

    Incorrect

    • A 25-year-old regular gym attendee has been using growth hormone injections to enhance his muscle mass. What potential risks is he now more susceptible to?

      Your Answer: Psoriasis

      Correct Answer: Diabetes mellitus type II

      Explanation:

      Excessive growth hormone can elevate the likelihood of developing type II diabetes mellitus. This is due to the hormone’s ability to release glucose from fat reserves, which raises its concentration in the bloodstream. As a result, the pancreas must produce more insulin to counteract the heightened glucose levels.

      Additional indications of surplus growth hormone may involve thickened skin, enlarged extremities, a protruding jaw, carpal tunnel syndrome, fatigue, muscle frailty, and high blood pressure.

      Understanding Growth Hormone and Its Functions

      Growth hormone (GH) is a hormone produced by the somatotroph cells in the anterior pituitary gland. It plays a crucial role in postnatal growth and development, as well as in regulating protein, lipid, and carbohydrate metabolism. GH acts on a transmembrane receptor for growth factor, leading to receptor dimerization and direct or indirect effects on tissues via insulin-like growth factor 1 (IGF-1), which is primarily secreted by the liver.

      GH secretion is regulated by various factors, including growth hormone releasing hormone (GHRH), fasting, exercise, and sleep. Conversely, glucose and somatostatin can decrease GH secretion. Disorders associated with GH include acromegaly, which results from excess GH, and GH deficiency, which can lead to short stature.

      In summary, GH is a vital hormone that plays a significant role in growth and metabolism. Understanding its functions and regulation can help in the diagnosis and treatment of GH-related disorders.

    • This question is part of the following fields:

      • Endocrine System
      6.7
      Seconds
  • Question 23 - Mr. Smith is a 54-year-old man who visits your GP clinic for his...

    Incorrect

    • Mr. Smith is a 54-year-old man who visits your GP clinic for his annual review of his type 2 diabetes. He informs you that he has been managing it through diet for a few years, but lately, he has gained some weight. His latest HbA1C reading is 9.8% (normal range 3.7-5.0%). You suggest continuous dietary advice and prescribe metformin to regulate his blood glucose levels. Which of the following statements about metformin is accurate?

      Your Answer: It can cause weight gain

      Correct Answer: It decreases hepatic gluconeogenesis

      Explanation:

      While some diabetic treatments such as insulin and sulfonylureas can lead to weight gain, metformin is not associated with this side effect. Metformin functions by enhancing insulin sensitivity and reducing hepatic gluconeogenesis, without directly impacting insulin secretion from pancreatic beta cells, thus it does not cause significant hypoglycemia. Ghrelin, a hormone that controls appetite, is not influenced by any diabetic medications.

      Understanding Diabetes Mellitus: A Basic Overview

      Diabetes mellitus is a chronic condition characterized by abnormally raised levels of blood glucose. It is one of the most common conditions encountered in clinical practice and represents a significant burden on the health systems of the developed world. The management of diabetes mellitus is crucial as untreated type 1 diabetes would usually result in death. Poorly treated type 1 diabetes mellitus can still result in significant morbidity and mortality. The main focus of diabetes management now is reducing the incidence of macrovascular and microvascular complications.

      There are different types of diabetes mellitus, including type 1 diabetes mellitus, type 2 diabetes mellitus, prediabetes, gestational diabetes, maturity onset diabetes of the young, latent autoimmune diabetes of adults, and other types. The presentation of diabetes mellitus depends on the type, with type 1 diabetes mellitus often presenting with weight loss, polydipsia, polyuria, and diabetic ketoacidosis. On the other hand, type 2 diabetes mellitus is often picked up incidentally on routine blood tests and presents with polydipsia and polyuria.

      There are four main ways to check blood glucose, including a finger-prick bedside glucose monitor, a one-off blood glucose, a HbA1c, and a glucose tolerance test. The diagnostic criteria are determined by WHO, with a fasting glucose greater than or equal to 7.0 mmol/l and random glucose greater than or equal to 11.1 mmol/l being diagnostic of diabetes mellitus. Management of diabetes mellitus involves drug therapy to normalize blood glucose levels, monitoring for and treating any complications related to diabetes, and modifying any other risk factors for other conditions such as cardiovascular disease. The first-line drug for the vast majority of patients with type 2 diabetes mellitus is metformin, with second-line drugs including sulfonylureas, gliptins, and pioglitazone. Insulin is used if oral medication is not controlling the blood glucose to a sufficient degree.

    • This question is part of the following fields:

      • Endocrine System
      16.5
      Seconds
  • Question 24 - A 54-year-old man with type 2 diabetes mellitus visits the Endocrinology clinic for...

    Incorrect

    • A 54-year-old man with type 2 diabetes mellitus visits the Endocrinology clinic for evaluation. He is currently on maximum doses of metformin and glibenclamide, but his HbA1c levels have increased from 58 mmol/mol to 67 mmol/mol over the past six months. The consultant recommends adding sitagliptin as a third antidiabetic medication. What is the mechanism of action of this new medication?

      Your Answer: Activate peroxisome proliferator-activated receptor gamma (PPAR-γ) to increase insulin sensitivity

      Correct Answer: Inhibit the peripheral breakdown of incretins, enhancing their ability to stimulate insulin release

      Explanation:

      Diabetes mellitus is a condition that has seen the development of several drugs in recent years. One hormone that has been the focus of much research is glucagon-like peptide-1 (GLP-1), which is released by the small intestine in response to an oral glucose load. In type 2 diabetes mellitus (T2DM), insulin resistance and insufficient B-cell compensation occur, and the incretin effect, which is largely mediated by GLP-1, is decreased. GLP-1 mimetics, such as exenatide and liraglutide, increase insulin secretion and inhibit glucagon secretion, resulting in weight loss, unlike other medications. They are sometimes used in combination with insulin in T2DM to minimize weight gain. Dipeptidyl peptidase-4 (DPP-4) inhibitors, such as vildagliptin and sitagliptin, increase levels of incretins by decreasing their peripheral breakdown, are taken orally, and do not cause weight gain. Nausea and vomiting are the major adverse effects of GLP-1 mimetics, and the Medicines and Healthcare products Regulatory Agency has issued specific warnings on the use of exenatide, reporting that it has been linked to severe pancreatitis in some patients. NICE guidelines suggest that a DPP-4 inhibitor might be preferable to a thiazolidinedione if further weight gain would cause significant problems, a thiazolidinedione is contraindicated, or the person has had a poor response to a thiazolidinedione.

    • This question is part of the following fields:

      • Endocrine System
      14.5
      Seconds
  • Question 25 - A 20-year-old man comes to the emergency department complaining of abdominal pain, vomiting,...

    Incorrect

    • A 20-year-old man comes to the emergency department complaining of abdominal pain, vomiting, polyuria, polydipsia, and confusion that have been present for the past 12 hours. During the examination, he shows mild generalized abdominal tenderness without guarding. His breathing is observed to be deep and rapid.

      The patient has a medical history of type 1 diabetes, but he confesses to being non-compliant with his insulin regimen.

      What is the probable pathophysiology behind his symptoms?

      Your Answer: Elevated serum lactate levels

      Correct Answer: Uncontrolled lipolysis which results in an excess of free fatty acids

      Explanation:

      The cause of DKA is uncontrolled lipolysis, leading to an excess of free fatty acids that are converted to ketone bodies. This results in high levels of ketones in the urine. Hypoglycemia activates the sympathetic nervous system. Lactic acidosis is similar to DKA but lacks the presence of ketones in urine. Appendicitis can cause abdominal pain, vomiting, and urinary symptoms, but the presence of ketones in urine suggests DKA. Urinary tract infections are rare in men under 50 and typically occur with abnormal anatomy or catheterization.

      Diabetic ketoacidosis (DKA) is a serious complication of type 1 diabetes mellitus, accounting for around 6% of cases. It can also occur in rare cases of extreme stress in patients with type 2 diabetes mellitus. DKA is caused by uncontrolled lipolysis, resulting in an excess of free fatty acids that are converted to ketone bodies. The most common precipitating factors of DKA are infection, missed insulin doses, and myocardial infarction. Symptoms include abdominal pain, polyuria, polydipsia, dehydration, Kussmaul respiration, and breath that smells like acetone. Diagnostic criteria include glucose levels above 11 mmol/l or known diabetes mellitus, pH below 7.3, bicarbonate below 15 mmol/l, and ketones above 3 mmol/l or urine ketones ++ on dipstick.

      Management of DKA involves fluid replacement, insulin, and correction of electrolyte disturbance. Fluid replacement is necessary as most patients with DKA are deplete around 5-8 litres. Isotonic saline is used initially, even if the patient is severely acidotic. Insulin is administered through an intravenous infusion, and correction of electrolyte disturbance is necessary. Long-acting insulin should be continued, while short-acting insulin should be stopped. Complications may occur from DKA itself or the treatment, such as gastric stasis, thromboembolism, arrhythmias, acute respiratory distress syndrome, acute kidney injury, and cerebral edema. Children and young adults are particularly vulnerable to cerebral edema following fluid resuscitation in DKA and often need 1:1 nursing to monitor neuro-observations, headache, irritability, visual disturbance, focal neurology, etc.

    • This question is part of the following fields:

      • Endocrine System
      24.5
      Seconds
  • Question 26 - A 14-year-old boy is brought to the clinic by his mother due to...

    Incorrect

    • A 14-year-old boy is brought to the clinic by his mother due to concerns about his height compared to other boys his age. The boy also shares that he often receives comments about his appearance, with some likening him to a toy doll. What can be inferred about the pattern of hormone release that he may be lacking?

      Your Answer: Released diurnally

      Correct Answer: It is released in a pulsatile manner

      Explanation:

      The doll-like appearance of the boy in his presentation suggests that he may be suffering from growth hormone deficiency, which can cause short stature, forehead prominence, and maxillary hypoplasia. The hypothalamus controls the release of growth hormone through the pulsatile release of growth hormone releasing hormone. Therefore, measuring GHRH levels is not a useful method for investigating growth hormone deficiency.

      Understanding Growth Hormone and Its Functions

      Growth hormone (GH) is a hormone produced by the somatotroph cells in the anterior pituitary gland. It plays a crucial role in postnatal growth and development, as well as in regulating protein, lipid, and carbohydrate metabolism. GH acts on a transmembrane receptor for growth factor, leading to receptor dimerization and direct or indirect effects on tissues via insulin-like growth factor 1 (IGF-1), which is primarily secreted by the liver.

      GH secretion is regulated by various factors, including growth hormone releasing hormone (GHRH), fasting, exercise, and sleep. Conversely, glucose and somatostatin can decrease GH secretion. Disorders associated with GH include acromegaly, which results from excess GH, and GH deficiency, which can lead to short stature.

      In summary, GH is a vital hormone that plays a significant role in growth and metabolism. Understanding its functions and regulation can help in the diagnosis and treatment of GH-related disorders.

    • This question is part of the following fields:

      • Endocrine System
      34.9
      Seconds
  • Question 27 - A 25-year-old male patient presents to the endocrine clinic with delayed-onset puberty. His...

    Incorrect

    • A 25-year-old male patient presents to the endocrine clinic with delayed-onset puberty. His history revealed a cleft palate as a child which had been repaired successfully. On direct questioning, he revealed he had anosmia but was told this was due to a minor head injury aged 5. On examination, he was 1.80 metres tall, had sparse pubic hair and small volume testes (Tanner staging grade 1).

      Blood results revealed:

      FSH 2 IU/L (1-7)
      LH 2 IU/L (1-8)
      Testosterone 240 ng/dL (280-1100)

      What is the most likely cause of this patient's condition?

      Your Answer: Turner's syndrome

      Correct Answer: Kallmann syndrome

      Explanation:

      The minor head injury is unlikely to be the cause of the patient’s anosmia. However, the combination of anosmia and cleft palate, along with the blood test results indicating hypogonadotropic hypogonadism, suggests that the patient may have Kallmann’s syndrome, which is an X-linked inherited disorder. Constitutional developmental delay is less likely due to the patient’s age and abnormal blood test results.

      Empty sella syndrome is a condition where the sella turcica, the area of the brain where the pituitary gland is located, is empty and filled with cerebrospinal fluid. Although this condition can be asymptomatic, it can also present with symptoms of hypopituitarism. However, since the patient also has anosmia and cleft palate, empty sella syndrome is less likely.

      Klinefelter’s syndrome is characterized by tall stature, gynecomastia, and small penis/testes. Blood tests would reveal elevated gonadotropins and low testosterone levels. However, since the patient’s FSH and LH levels are low, Klinefelter’s syndrome can be ruled out.

      Kallmann’s syndrome is a condition that can cause delayed puberty due to hypogonadotropic hypogonadism. It is often inherited as an X-linked recessive trait and is believed to be caused by a failure of GnRH-secreting neurons to migrate to the hypothalamus. One of the key indicators of Kallmann’s syndrome is anosmia, or a lack of smell, in boys with delayed puberty. Other features may include hypogonadism, cryptorchidism, low sex hormone levels, and normal or above-average height. Some patients may also have cleft lip/palate and visual/hearing defects.

      Management of Kallmann’s syndrome typically involves testosterone supplementation. Gonadotrophin supplementation may also be used to stimulate sperm production if fertility is desired later in life. It is important for individuals with Kallmann’s syndrome to receive appropriate medical care and monitoring to manage their symptoms and ensure optimal health outcomes.

    • This question is part of the following fields:

      • Endocrine System
      19.7
      Seconds
  • Question 28 - A 35-year-old woman is referred to the endocrine clinic due to missed periods...

    Incorrect

    • A 35-year-old woman is referred to the endocrine clinic due to missed periods and lactation. She has also gained weight and experiences vaginal dryness. The endocrinologist decides to measure her prolactin levels. What hormone is responsible for suppressing the release of prolactin from the pituitary gland?

      Your Answer: Oestrogen

      Correct Answer: Dopamine

      Explanation:

      Dopamine consistently prevents the release of prolactin.

      Understanding Prolactin and Its Functions

      Prolactin is a hormone that is produced by the anterior pituitary gland. Its primary function is to stimulate breast development and milk production in females. During pregnancy, prolactin levels increase to support the growth and development of the mammary glands. It also plays a role in reducing the pulsatility of gonadotropin-releasing hormone (GnRH) at the hypothalamic level, which can block the action of luteinizing hormone (LH) on the ovaries or testes.

      The secretion of prolactin is regulated by dopamine, which constantly inhibits its release. However, certain factors can increase or decrease prolactin secretion. For example, prolactin levels increase during pregnancy, in response to estrogen, and during breastfeeding. Additionally, stress, sleep, and certain drugs like metoclopramide and antipsychotics can also increase prolactin secretion. On the other hand, dopamine and dopaminergic agonists can decrease prolactin secretion.

      Overall, understanding the functions and regulation of prolactin is important for reproductive health and lactation.

    • This question is part of the following fields:

      • Endocrine System
      7.9
      Seconds
  • Question 29 - A 62-year-old male with type 2 diabetes is urgently referred by his GP...

    Correct

    • A 62-year-old male with type 2 diabetes is urgently referred by his GP due to poor glycaemic control for the past three days, with home blood glucose readings around 25 mmol/L. He is currently being treated with metformin and lisinopril. Yesterday, his GP checked his U+E and found that his serum sodium was 138 mmol/L (137-144), serum potassium was 5.8 mmol/L (3.5-4.9), serum urea was 20 mmol/L (2.5-7.5), and serum creatinine was 350 µmol/L (60-110). On examination, he has a temperature of 39°C, a pulse of 108 bpm, a blood pressure of 96/60 mmHg, a respiratory rate of 32/min, and oxygen saturations of 99% on air. His cardiovascular, respiratory, and abdominal examination are otherwise normal. Further investigations reveal a plasma glucose level of 17 mmol/L (3.0-6.0) and urine analysis showing blood ++ and protein ++, but ketones are negative. What is the likely diagnosis?

      Your Answer: Sepsis

      Explanation:

      The causes of septic shock are important to understand in order to provide appropriate treatment and improve patient outcomes. Septic shock can cause fever, hypotension, and renal failure, as well as tachypnea due to metabolic acidosis. However, it is crucial to rule out other conditions such as hyperosmolar hyperglycemic state or diabetic ketoacidosis, which have different symptoms and diagnostic criteria.

      While metformin can contribute to acidosis, it is unlikely to be the primary cause in this case. Diabetic patients may be prone to renal tubular acidosis, but this is not likely to be the cause of an acute presentation. Instead, a type IV renal tubular acidosis, characterized by hyporeninaemic hypoaldosteronism, may be a more likely association.

      Overall, it is crucial to carefully evaluate patients with septic shock and consider all possible causes of their symptoms. By ruling out other conditions and identifying the underlying cause of the acidosis, healthcare providers can provide targeted treatment and improve patient outcomes. Further research and education on septic shock and its causes can also help to improve diagnosis and treatment in the future.

    • This question is part of the following fields:

      • Endocrine System
      7.1
      Seconds
  • Question 30 - A 34-year-old male presents with tingling in his thumb, index, and middle finger,...

    Incorrect

    • A 34-year-old male presents with tingling in his thumb, index, and middle finger, along with complaints of excessive fatigue and snoring. Upon examination, he displays a prominent brow ridge and significant facial changes over time. Following blood tests and an MRI scan, the patient is prescribed octreotide. What is the mechanism of action of this medication?

      Your Answer:

      Correct Answer: Somatostatin analogue

      Explanation:

      Acromegaly is a condition that results from excessive growth hormone production. The release of growth hormone is directly inhibited by somatostatin, which is why somatostatin analogues are used to treat acromegaly.

      To answer the question, one must first recognize the symptoms of acromegaly, such as carpal tunnel syndrome, sleep apnea, and changes in facial features over time. The second part of the question involves identifying octreotide as a somatostatin analogue commonly used to treat acromegaly.

      While dopamine agonists were previously used to treat acromegaly, they are no longer preferred due to the availability of more effective treatments. Dopamine antagonists have never been used to treat acromegaly. Pegvisomant is an example of a growth hormone antagonist, but antagonists for insulin growth factor-1 release have not yet been developed.

      Acromegaly is a condition that can be managed through various treatment options. The first-line treatment for the majority of patients is trans-sphenoidal surgery. However, if the pituitary tumour is inoperable or surgery is unsuccessful, medication may be indicated. One such medication is a somatostatin analogue, which directly inhibits the release of growth hormone. Octreotide is an example of this medication and is effective in 50-70% of patients. Another medication is pegvisomant, which is a GH receptor antagonist that prevents dimerization of the GH receptor. It is administered once daily subcutaneously and is very effective, decreasing IGF-1 levels in 90% of patients to normal. However, it does not reduce tumour volume, so surgery is still needed if there is a mass effect. Dopamine agonists, such as bromocriptine, were the first effective medical treatment for acromegaly but are now superseded by somatostatin analogues and are only effective in a minority of patients. External irradiation may be used for older patients or following failed surgical/medical treatment.

    • This question is part of the following fields:

      • Endocrine System
      0
      Seconds

SESSION STATS - PERFORMANCE PER SPECIALTY

Endocrine System (7/29) 24%
Passmed