Endocrine and Metabolic Disorders

Acromegaly is caused by excessive secretion of growth hormone in adults, leading to enlargement of bones in hands, feet, and face. In children, excess growth hormone causes gigantism. Grave's disease is thyroid-related, Gull's disease is hypothyroidism, and dwarfism is caused by growth hormone deficiency.

This is the correct option. Thyroid hormone causes myxoderma (in adults). Insulin hormone causes diabetes mellitus. Aldosterone hormone causes Addison's disease.

Mineralocorticoid excess (such as in Conn's syndrome or hyperaldosteronism) causes metabolic alkalosis through multiple mechanisms: increased H+ ion secretion in the renal tubules, hypokalemia (which leads to intracellular H+ shift), and increased urinary acid excretion. The opposite condition - mineralocorticoid deficiency - would cause metabolic acidosis, not alkalosis.

Thiazides DECREASE calcium excretion (they increase calcium reabsorption in DCT), making them useful in hypercalciuric stone formers. The question asks for what they DON'T cause. They DO cause hyperglycemia, increased uric acid (precipitating gout), and are useful in CHF for their diuretic effect.

Loop diuretics like furosemide actually DECREASE serum calcium by increasing urinary calcium excretion, so they do NOT cause hypercalcemia. Lithium causes hypercalcemia by increasing parathyroid hormone secretion. Vitamin D intoxication directly increases calcium absorption and bone resorption.

Glucocorticoids like prednisone cause hyperglycemia by promoting gluconeogenesis, reducing glucose uptake in peripheral tissues, and inducing insulin resistance. Beta blockers can mask hypoglycemia symptoms but don't directly raise blood glucose. NSAIDs have minimal effect on glucose metabolism.

SIADH (Syndrome of Inappropriate ADH) causes euvolemic or hypervolemic hyponatremia with concentrated urine and hypouricemia (increased renal uric acid excretion). Volume depletion causing hypotension is NOT seen in SIADH - that would occur in true volume depletion states like dehydration or hemorrhage. SIADH patients are typically normotensive.

Low dietary calcium intake leads to hypocalcemia, which stimulates the parathyroid glands to secrete more parathyroid hormone (PTH) via negative feedback. PTH acts to restore serum calcium by increasing bone resorption, enhancing renal calcium reabsorption, and stimulating renal 1-alpha-hydroxylase activity (not 24-hydroxylase). Calcitonin levels would decrease, not increase, as it responds to hypercalcemia. Phosphate levels typically decrease due to PTH's phosphaturic effect.

Cushing's disease typically causes sustained hypertension (not episodic) due to cortisol excess, along with central obesity, easy bruisability from skin fragility, and glucose intolerance from cortisol-induced insulin resistance. Episodic hypertension is more characteristic of pheochromocytoma. Episodic hypertension is the exception among these findings.

Hypertension with hypokalemia is seen in renal artery stenosis (renin-mediated), Cushing's disease (cortisol excess), and primary hyperaldosteronism (Conn's syndrome) due to mineralocorticoid excess. End-stage renal disease typically causes hypertension with hyperkalemia (not hypokalemia) due to reduced potassium excretion. ESRD is the exception.

Von Hippel-Lindau (VHL) syndrome is a genetic condition associated with tumors such as hemangioblastomas, pheochromocytomas, renal cell carcinomas, endolymphatic sac tumors, and islet cell tumors. Hemangioendotheliomas are vascular tumors not characteristic of VHL syndrome, making option C the correct exception.

The triad of amenorrhea, weight loss, and an eating disorder presentation in a young woman is classic for anorexia nervosa, which causes hypothalamic suppression. Occult malignancy, HIV, and hypothyroidism would present with different clinical features (weight gain in hypothyroidism, systemic symptoms in cancer/HIV).

Iodine deficiency causes goiter (enlarged thyroid gland) because iodine is essential for thyroid hormone production. Rickets is from vitamin D deficiency, diabetes involves insulin, and beriberi is from vitamin B1 (thiamine) deficiency.

Hypocalcemia results from insufficient secretion of parathyroid hormone (PTH). PTH normally increases blood calcium levels by stimulating bone resorption, enhancing renal calcium reabsorption, and promoting intestinal calcium absorption through vitamin D activation.

Pituitary nanism (dwarfism) is caused by hyposecretion (underproduction) of somatotrophic hormone (growth hormone, GH) from the anterior pituitary gland. ACTH affects adrenal cortex function, not growth.