In a patient with diabetes insipidus:

Correct Answer: B

Rationale: The correct answer is B: Intranasal vasopressin may be helpful. In diabetes insipidus, there is a deficiency of vasopressin leading to excessive urination and thirst. Administering vasopressin intranasally can help replace the deficient hormone, reducing urine output and thirst. Hypernatremia (choice A) can occur due to excessive water loss, but it is not always present. There is no osmolar gap (choice C) in diabetes insipidus. Urine specific gravity (choice D) is typically low in diabetes insipidus due to the dilute urine produced.

Correct Answer: C

Rationale: The correct answer is C: Bi-temporal hemianopia. Pituitary adenoma compressing the optic chiasm typically leads to bi-temporal hemianopia due to compression of the crossing fibers from the nasal visual fields. This results in loss of peripheral vision in both temporal visual fields. A: Bilateral inferior visual field deficits and B: Bilateral superior visual field deficits are less likely as they are not typical patterns associated with optic chiasm compression. D: Right homonymous hemianopia is incorrect as it is not associated with compression of the optic chiasm by a pituitary adenoma.

Correct Answer: B

Rationale: Correct Answer: B (Rheumatic carditis) Rationale: 1. Rheumatic carditis is a heart condition, which may lead to a decreased cardiac output and subsequently a lower pulse rate during sleep. 2. Anxiety neurosis can lead to increased sympathetic activity, causing an elevated pulse rate during sleep. 3. Pulmonary tuberculosis can cause systemic inflammation and increased metabolic demand, resulting in an elevated pulse rate during sleep. 4. Atropine, a parasympatholytic drug, inhibits the action of the parasympathetic nervous system, leading to an increased pulse rate.

Correct Answer: B

Rationale: The correct answer is B: Bitemporal Hemianopsia. Pituitary adenomas can compress the optic chiasm, leading to bitemporal hemianopsia. This occurs due to the loss of peripheral vision on both sides. Carpo-pedal spasm (A) is associated with hypocalcemia, Chvostek's sign (C) is a facial spasm seen in hypocalcemia, and tremor (D) can be seen in conditions such as Parkinson's disease, but they are not specific to pituitary adenoma. Bitemporal hemianopsia is a classic sign of pituitary adenoma due to its location near the optic chiasm.

Correct Answer: D

Rationale: The correct answer is D: Fine hairs. In secondary hypothyroidism, the pituitary gland fails to produce enough thyroid-stimulating hormone (TSH), resulting in low thyroid hormone levels. Fine hairs (or hair thinning) is a symptom of hyperthyroidism, not hypothyroidism. Normal cholesterol levels (Choice A) are seen in secondary hypothyroidism due to decreased metabolic rate. Menorrhagia (Choice B) can occur due to hormonal imbalances caused by untreated hypothyroidism. Low TSH levels (Choice C) are a characteristic feature of secondary hypothyroidism as the pituitary gland is not producing enough TSH to stimulate the thyroid gland.