In central and nephrogenic diabetes insipidus (DI), urinary osmolality will be less than 300 mOsm/kg after water deprivation. After the administration of ADH, the osmolality will rise to more than 750 mOsm/kg in central DI but will not rise at all in nephrogenic DI.

In primary polydipsia, water deprivation results in an increase in urine osmolality, anywhere between 300 – 800 mOsm/Kg (usually up to 600 – 700 mOsm/Kg), without a substantial increase in plasma osmolality, but the increase in urine osmolality is not as substantial as in a normal response.

The patient is most likely to have Postpartum thyroiditis which goes through 2 phases; hypothyroid and a hyperthyroid phase.
The hyperthyroid phase of postpartum thyroiditis occurs between 2 and 10 months postpartum. Most commonly, it presents at 3 months. Symptoms more common in women with hyperthyroid postpartum thyroiditis include palpitations, fatigue, heat intolerance, and irritability/nervousness. The frequency of asymptomatic hyperthyroidism is 33%.
Untreated, the hyperthyroidism resolves spontaneously within 2–3 months. This phase is diagnosed by the combination of a low serum TSH concentration in the presence of thyroid peroxidase antibodies, in women who are TSH receptor antibody-negative. Free T4 levels are typically elevated but may be normal.
Treatment of hyperthyroidism, when necessary, is based on symptom severity and should be a joint decision of patient and physician. Beta-blockers such as propranolol are given to alleviate palpitations, irritability, and nervousness. The morbidity associated with treatment is the side effects of beta-blockade. The downside of withholding treatment is allowing the woman to remain symptomatic. Antithyroid medicines (thioureas) are not a potential treatment alternative, because the hyperthyroidism is caused by destructive thyroiditis resulting in the release of preformed thyroid hormone.

Biguanides (Metformin):
People who take metformin alone should be able to fast safely given that the possibility of hypoglycaemia is minimal. However, patients should modify its dose and administration timing to provide two-thirds of the total daily dose, which should be taken immediately with the sunset meal, while the other third is taken before the predawn meal.

Thiazolidinediones: No change needed.

Sulfonylurea:
Once-daily sulfonylurea (such as glimepiride or gliclazide MR): the total daily dose should be taken with the sunset meal.
Shorter-acting sulfonylurea (such as gliclazide twice daily): the same daily dose remains unchanged, and one dose should be taken at the sunset meal and the other at the predawn meal.
Long-acting sulfonylurea (such as glibenclamide): these agents should be avoided.

It is important that diabetic patients to eat a healthy balanced diet and choose foods with a low glycaemic index (such as complex carbohydrates), which can help to maintain blood glucose levels during fasting. Moreover, it is crucial to consume adequate fluids to prevent dehydration. Physical activity is encouraged, especially during non-fasting periods.

Low body weight. Excessively low body weight — about 10 percent under normal weight — interrupts many hormonal functions in your body, potentially halting ovulation.
In Polycystic ovaries there is excess weight gain.

The patient is most likely to have Addison’s disease as he has a history of autoimmune disease, hyperkalaemia and hypotension.
It is important to keep an Addisonian crisis on the differential in cases of shock, especially since adrenal crisis can be the patient’s first presentation of adrenal insufficiency.
Patients with Addison’s disease are prone to developing hypoglycaemia due to loss of the glucogenic effect of glucocorticoids. Given the sudden deterioration, a glucose level must be checked.

Dapagliflozin works by inhibiting sodium glucose cotransporter 2 (SGLT2) and blocking resorption of glucose in the kidney, leading to an increase in urinary glucose excretion and lowering of both plasma glucose levels and body weight.
All studies with SGLT2 inhibitors have found significant reductions in BP, with greater reductions seen in systolic (1.66 to 6.9mmHg) than diastolic (0.88 to 3.5mmHg) BP.
While some trials have shown no change in lipid parameters, others have shown a modest but statistically significant increase in both HDL and LDL cholesterol with no effect on triglycerides or the LDL/HDL ratio.

The patients high morning blood sugar levels are suggestive to Somogyi Phenomenon which suggests that hypoglycaemia during the late evening induced by insulin could cause a counter regulatory hormone response that produces hyperglycaemia in the early morning.
Substitution of regular insulin with an immediate-acting insulin analogue, such as Humulin lispro, may be of some help.

Androgen insensitivity syndrome (AIS), previously referred to as testicular feminization, is an X-linked disorder in which the patients are genotypically male (possessing and X and Y chromosome) and phenotypically female. This disorder is rare, with reported incidences from 1 in 20,000 to 1 in 60,000 live male births, and is the result of a missing gene on the X chromosome that is responsible for the cytoplasmic or nuclear testosterone receptor. In its absence, the gonad, which is a testis, produces normal amounts of testosterone; however, the end tissues are unable to respond due to the deficient receptors leading to the external genitalia developing in a female fashion. Anti-mullerian hormone, which is produced by the testis, is normal in these patients, leading to regression of the Mullerian duct. Wolffian duct development, which depends on testosterone, does not occur as the ducts lack the receptors.
The cumulative effect is a genotypic male with normal external female genitalia (without pubic or axillary hair), no menses, normal breast development, short or absent vagina, no internal sex organs, and the presence of testis. Frequently, these patients have bilateral inguinal hernias in childhood, and their presence should arouse suspicion of the diagnosis.

The diagnosis of polycystic ovarian syndrome (PCOS) is based on hyperandrogenism or chronic anovulation in the absence of specific pituitary and/or adrenal disease.
Pelvic ultrasonography may be very helpful in the evaluation as well, but polycystic ovaries are not specific for PCOS with over 20% of “normal” women having this finding. The number of follicles and ovary volume are both important in the ultrasound evaluation. The criteria for PCOS put forth by Adams et al. are the most often cited: the presence of ≥10 cysts measuring 2–8 mm around a dense core of stroma or scattered within an increased amount of stroma.
A recent proposal to modify these criteria has been put forth by Jonard et al.: “increased ovarian area (>5.5cm2) or volume (>11 mL) and/or presence of ≥12 follicles measuring 2 to 9 mm in diameter (mean of both ovaries)”.
These criteria have a specificity of 99% and a sensitivity of 75% for the diagnosis of PCOS.

Up to 10% of postpartum women may develop lymphocytic thyroiditis (postpartum thyroiditis) in the 2-12 months after delivery. The frequency may be as high as 25% in women with type 1 diabetes mellitus.

Some patients return spontaneously to a euthyroid state within a few months, but most patients experience a phase of hypothyroidism that takes 2 to 6 months to resolve; of this group, some develop permanent hypothyroidism. About 50% of patients, however, will develop permanent hypothyroidism within 5 years of the diagnosis of postpartum thyroiditis.

High titres of anti-TPO antibodies during pregnancy have been reported to have high sensitivity and specificity for postpartum autoimmune thyroid disease.

Treatment with fibrates, a widely used class of lipid-modifying agents, results in a substantial decrease in plasma triglycerides and is usually associated with a moderate decrease in LDL cholesterol and an increase in HDL cholesterol concentrations.
Evidence from studies is available to implicate 5 major mechanisms underlying the above-mentioned modulation of lipoprotein phenotypes by fibrates:
1. Induction of lipoprotein lipolysis.
2. Induction of hepatic fatty acid (FA) uptake and reduction of hepatic triglyceride production.
3. Increased removal of LDL particles. Fibrate treatment results in the formation of LDL with a higher affinity for the LDL receptor, which is thus catabolized more rapidly.
4. Reduction in neutral lipid (cholesteryl ester and triglyceride) exchange between VLDL and HDL may result from decreased plasma levels of TRL.
5. Increase in HDL production and stimulation of reverse cholesterol transport. Fibrates increase the production of apoA-I and apoA-II in the liver, which may contribute to the increase of plasma HDL concentrations and a more efficient reverse cholesterol transport.

Elevated TSH (usually 4.5-10.0 mIU/L) with normal free T4 is considered mild or subclinical hypothyroidism.
Hypothyroidism commonly manifests as a slowing in physical and mental activity but may be asymptomatic. Symptoms and signs are often subtle and neither sensitive nor specific.
The following are symptoms of hypothyroidism:
– Fatigue, loss of energy, lethargy
– Weight gain
– Decreased appetite
– Cold intolerance
– Dry skin
– Hair loss
– Sleepiness
– Muscle pain, joint pain, weakness in the extremities
– Depression
– Emotional lability, mental impairment
– Forgetfulness, impaired memory, inability to concentrate
– Constipation
– Menstrual disturbances, impaired fertility
– Decreased perspiration
– Paraesthesia and nerve entrapment syndromes
– Blurred vision
– Decreased hearing
– Fullness in the throat, hoarseness
Physical signs of hypothyroidism include the following:
– Weight gain
– Slowed speech and movements
– Dry skin
– Jaundice
– Pallor
– Coarse, brittle, straw-like hair
– Loss of scalp hair, axillary hair, pubic hair, or a combination
– Dull facial expression
– Coarse facial features
– Periorbital puffiness
– Macroglossia
– Goitre (simple or nodular)
– Hoarseness
– Decreased systolic blood pressure and increased diastolic blood pressure
– Bradycardia
– Pericardial effusion
– Abdominal distention, ascites (uncommon)
– Hypothermia (only in severe hypothyroid states)
– Nonpitting oedema (myxoedema)
– Pitting oedema of lower extremities
– Hyporeflexia with delayed relaxation, ataxia, or both.

The water deprivation test (i.e., the Miller-Moses test), is a semiquantitative test to ensure adequate dehydration and maximal stimulation of ADH for diagnosis. It is typically performed in patients with more chronic forms of Diabetes Insipidus (DI). The extent of deprivation is usually limited by the patient’s thirst or by any significant drop in blood pressure or related clinical manifestation of dehydration.

In healthy individuals, water deprivation leads to a urinary osmolality that is 2-4 times greater than plasma osmolality. Additionally, in normal, healthy subjects, administration of ADH produces an increase of less than 9% in urinary osmolality. The time required to achieve maximal urinary concentration ranges from 4-18 hours.

In central and nephrogenic DI, urinary osmolality will be less than 300 mOsm/kg after water deprivation. After the administration of ADH, the osmolality will rise to more than 750 mOsm/kg in central DI but will not rise at all in nephrogenic DI. In primary polydipsia, urinary osmolality will be above 750 mOsm/kg after water deprivation.
A urinary osmolality that is 300-750 mOsm/kg after water deprivation and remains below 750 mOsm/kg after administration of ADH may be seen in partial central DI, partial nephrogenic DI, and primary polydipsia.

During pregnancy, profound changes in thyroid physiology occur to provide sufficient thyroid hormone (TH) to both the mother and foetus. This is particularly important during early pregnancy because the fetal thyroid starts to produce considerable amounts of TH only from approximately 20 weeks of gestation, until which time the foetus heavily depends on the maternal supply of TH. This supply of TH to the foetus, as well as increased concentrations of TH binding proteins (thyroxine-binding globulin) and degradation of TH by placental type 3 iodothyronine deiodinase, necessitate an increased production of maternal TH. This requires an intact thyroid gland and adequate availability of dietary iodine and is in part mediated by the pregnancy hormone human chorionic gonadotropin, which is a weak agonist of the thyroid-stimulating hormone (TSH) receptor. As a consequence, serum-free thyroxine (FT4) concentrations increase and TSH concentrations decrease from approximately the eighth week throughout the first half of pregnancy, resulting in different reference intervals for TSH and FT4 compared to the non-pregnant state.

The use of hormone replacement therapy (HRT) based on unopposed oestrogen increases the risk of endometrial cancer, and uterine hyperplasia or cancer.
Evidence from randomized controlled studies showed a definite association between HRT and uterine hyperplasia and cancer. HRT based on unopposed oestrogen is associated with this observed risk, which is unlike the increased risk of breast cancer linked with combined rather than unopposed HRT.

Cabergoline, an ergot derivative, is a long-acting dopamine agonist. It is usually better tolerated than Bromocriptine (BEC), and its efficacy profiles are somewhat superior to those of BEC. It offers the convenience of twice-a-week administration, with a usual starting dose of 0.25 mg biweekly to a maximum dose of 1 mg biweekly. Some studies have shown efficacy even with once-a-week dosing. Cabergoline appears to be more effective in lowering prolactin levels and restoring ovulation. Up to 70% of patients who do not respond to BEC respond to cabergoline.

Insulin is produced by the beta-cells in the islets of Langerhans in the pancreas while Glucagon is secreted from the alpha cells of the pancreatic islets of Langerhans.
Type 1 diabetes mellitus is the culmination of lymphocytic infiltration and destruction of the beta cells of the islets of Langerhans in the pancreas. As beta-cell mass declines, insulin secretion decreases until the available insulin is no longer adequate to maintain normal blood glucose levels. After 80-90% of the beta cells are destroyed, hyperglycaemia develops and diabetes may be diagnosed.

Lactic acidosis is occasionally responsible for metabolic acidosis in diabetics. It may occur in the presence of normal blood levels of the ketone bodies, and such cases are often described as having “non-ketotic diabetic acidosis.
It is most commonly associated with tissue hypoperfusion and states of acute circulatory failure.
Appropriate measures include treatment of shock, restoration of circulating fluid volume, improved cardiac function, identification of sepsis source, early antimicrobial intervention, and resection of any potential ischemic regions. Reassessment of lactate levels for clearance assists ongoing medical management.

The patient is most likely to have Medullary Thyroid Carcinoma (MTC).
Sporadic, or isolated MTC accounts for 75% of cases and inherited MTC constitutes the rest.
Inherited MTC occurs in association with multiple endocrine neoplasia (MEN) type 2A and 2B syndromes, but non-MEN familial MTC also occurs.
A 24-hour urinalysis for catecholamine metabolites (e.g., vanillylmandelic acid [VMA], metanephrine) has to be done to rule out concomitant pheochromocytoma in patients with MEN type 2A or 2B, as Pheochromocytoma must be treated before MTC.

Insulin remains the standard of care for the treatment of uncontrolled gestational diabetes. Tight control maintained in the first trimester and throughout pregnancy plays a vital role in decreasing poor fetal outcomes, including structural anomalies, macrosomia, hypoglycaemia of the new-born, adolescent and adult obesity, and diabetes.
The baby is already large for dates so nutritional therapy can not be used alone.

Several dipeptidyl peptidase-4 (DPP-4) inhibitors are in clinical development; these are orally active and increase levels of active glucagon-like peptide-1 (GLP-1), which in turn increases insulin secretion and reduces glucagon secretion, thereby lowering glucose levels.
Sitagliptin and vildagliptin both have a long duration of action, allowing once-daily administration. Both sitagliptin and vildagliptin are safe and tolerable with a low risk of hypoglycaemia. In drug-naïve subjects with type 2 diabetes, both sitagliptin and vildagliptin reduce A1C levels by ,1% as monotherapy.

Intensive physical training and participation in competitive sports during childhood and early adolescence may affect athletes’ pubertal development.
Female athletes who do not begin secondary sexual development by the age of 14 or menstruation by the age of 16 warrant a comprehensive evaluation and treatment.
Since she is still 14, adequate diet and observation are enough.

11-beta hydroxylase is stimulated by ACTH and responsible for conversion of 11-deoxycortisol to cortisol and deoxycorticosterone to corticosterone.

In 11-beta hydroxylase deficiency, the previously mentioned conversions are partially blocked, leading to:
– Increased levels of ACTH
– Accumulation of 11-deoxycortisol (which has limited biological activity) and deoxycorticosterone (which has mineralocorticoid activity)
– Overproduction of adrenal androgens (DHEA, androstenedione, and testosterone)

Primary hyperaldosteronism, also known as Conn’s Syndrome, is one of the most common causes of secondary hypertension (HTN).
The common clinical scenarios in which the possibility of primary hyperaldosteronism should be considered include the following:
– Patients with spontaneous or unprovoked hypokalaemia, especially if the patient is also hypertensive
– Patients who develop severe and/or persistent hypokalaemia in the setting of low to moderate doses of potassium-wasting diuretics
– Patients with treatment-refractory/-resistant hypertension (HTN)
Patients with severe hypokalaemia report fatigue, muscle weakness, cramping, headaches, and palpitations. They can also have polydipsia and polyuria from hypokalaemia-induced nephrogenic diabetes insipidus. Long-standing HTN may lead to cardiac, retinal, renal, and neurologic problems, with all the associated symptoms and signs.

The patient has hyperinsulinemia and hypoglycaemia, but her C-peptide levels are normal. This is strongly suggestive of the fact that she is self-administering insulin.
In Insulinoma, common diagnostic criteria include:
– blood glucose level < 50 mg/dl with hypoglycaemic symptoms,
– relief of symptoms after eating
– absence of sulfonylurea on plasma assays.
The classic diagnostic criteria include the demonstration of the following during a supervised fast:
Increased plasma insulin level
Increased C peptide level
Increased proinsulin level
However, the patient has normal C-peptide levels.
In type-1 diabetes mellitus, insulin and C-peptide levels are low.

The patient most likely has Klinefelter’s syndrome.
Klinefelter syndrome (KS) refers to a group of chromosomal disorders in which the normal male karyotype, 46,XY, has at least one extra X chromosome. XXY aneuploidy, the most common human sex chromosome disorder. It is also the most common chromosomal disorder associated with male hypogonadism and infertility.
Klinefelter syndrome is characterized by hypogonadism (micro-orchidism, oligospermia/azoospermia), gynecomastia in late puberty, hyalinization and fibrosis of the seminiferous tubules, elevated urinary gonadotropin levels, and behavioural concerns.

Selective sodium-glucose transporter-2 (SGLT2) is expressed in the proximal renal tubules and is responsible for the majority of the reabsorption of filtered glucose from the tubular lumen.
Empagliflozin; SGLT2 inhibitors reduce glucose reabsorption and lower the renal threshold for glucose, thereby increasing urinary glucose excretion, thus increasing the risk of urinary tract infections.

The somatotroph cells of the anterior pituitary gland produce growth hormone (GH).
GH deficiency in adults usually manifests as reduced physical performance and impaired psychological well-being. It results in alterations in the physiology of different systems of the body, manifesting as altered lipid metabolism, increased subcutaneous and visceral fat, decreased muscle mass, decreased bone density, low exercise performance, and reduced quality of life.

Indications for surgery for the treatment of primary hyperparathyroidism:
1. Symptoms of hypercalcaemia such as thirst, frequent or excessive urination, or constipation
2. End-organ disease (renal stones, fragility fractures or osteoporosis)
3. An albumin-adjusted serum calcium level of 2.85 mmol/litre or above.

Patients who have autonomously functioning nodules should be treated definitely with radioactive iodine or surgery.
Na131 I treatment – In the United States and Europe, radioactive iodine is considered the treatment of choice for Toxic Nodular Goitre. Except for pregnancy, there are no absolute contraindications to radioiodine therapy.