Endocrinology Practice Questions -Nurselytic

Correct Answer: C

Rationale: Increased parathyroid hormone (PTH) concentration is associated with tetany because PTH helps regulate calcium levels in the blood. When calcium levels are low, PTH is released to stimulate the release of calcium from bones and increase calcium absorption from the intestines. Tetany is characterized by muscle cramps and spasms due to low calcium levels, which can occur when PTH levels are elevated.

A: Vitamin D toxicity is associated with high levels of calcium in the blood, not low calcium levels as seen in tetany.
B: Rickets is a condition caused by vitamin D deficiency, leading to impaired bone growth and development, not directly related to elevated PTH levels.
D: Reduced excretion of phosphate is not directly linked to elevated PTH levels, as PTH primarily regulates calcium levels.

Correct Answer: C

Rationale: The correct answer is C: SIADH. Secondary hyperaldosteronism is characterized by increased aldosterone production due to factors outside of the adrenal glands, such as increased renin-angiotensin-aldosterone system activation. SIADH does not involve aldosterone, but rather involves inappropriate secretion of antidiuretic hormone leading to hyponatremia. In contrast, congestive cardiac failure, nephrotic syndrome, and cirrhosis of the liver can all lead to secondary hyperaldosteronism due to mechanisms such as decreased effective circulating volume, renal hypoperfusion, and increased angiotensin II levels, respectively.

Correct Answer: B

Rationale: The correct answer is B: Weight loss. Hypothyroidism is characterized by an underactive thyroid gland, leading to a decreased metabolic rate. This typically results in weight gain, not weight loss.

Choices A, C, and D are all associated with hypothyroidism. Loss of libido can occur due to hormonal imbalances, cardiac failure can result from the decreased metabolic rate affecting the heart, and organic psychosis can be a symptom of severe untreated hypothyroidism.

Correct Answer: C

Rationale: Erythropoietin is primarily secreted from the kidney, specifically by the Juxtaglomerular cells in the kidney's cortex. These cells are responsible for sensing oxygen levels and regulating erythropoietin production accordingly. Mesenchymal tumors, cerebellar haemangioblastoma, and lymphoma are not associated with erythropoietin secretion, making them incorrect choices. Mesenchymal tumors originate from connective tissues, cerebellar haemangioblastoma is a type of brain tumor, and lymphoma is a cancer of the lymphatic system. Only the Juxtaglomerular cells in the kidney have the physiological role of secreting erythropoietin in response to hypoxia.

Correct Answer: A

Rationale: The correct answer is A: Cirrhosis. In cirrhosis, there is a decrease in the binding proteins for T4, leading to decreased total T4 levels in the plasma. Pregnancy, euthyroid sick syndrome, and familial excess thyroid binding globulin are all conditions associated with increased total T4 levels due to various physiological changes. In pregnancy, there is an increase in thyroid hormone production to support fetal development. Euthyroid sick syndrome is a condition where there is a decrease in binding proteins, leading to an increase in free T4 levels but normal total T4 levels. Familial excess thyroid binding globulin causes an increase in total T4 levels due to excessive binding proteins.