Endocrinology — MCQs

Endocrinology Indian Medical PG Practice Questions and MCQs

Question 1651: Hot flushes are not associated with which of the following?

A. Medical castration
B. Surgical castration
C. Ketoconazole therapy
D. Radical prostatectomy (Correct Answer)

Explanation: ***Radical prostatectomy*** - This procedure surgically removes the prostate gland but **does not directly impact hormone levels** that cause hot flushes. - While it treats prostate cancer, it does not induce **androgen deprivation**, which is the primary cause of hot flushes in men. *Medical castration* - This refers to the use of drugs (e.g., **GnRH agonists/antagonists**) to **suppress testosterone production** or action. - The resulting low testosterone levels commonly lead to symptoms like **hot flushes**, similar to menopause in women. *Surgical castration* - This involves the surgical removal of the testes (orchiectomy), which are the primary source of testosterone in men. - The sudden and significant **drop in testosterone** after orchiectomy frequently causes **hot flushes**. *Ketoconazole therapy* - **Ketoconazole** is an antifungal medication that, at high doses, can **inhibit adrenal and gonadal steroid synthesis**, including testosterone. - This leads to a state of **chemical castration** with a decrease in testosterone, often resulting in **hot flushes** as a side effect.

Question 1652: What is the most common cause of hypercalcemia in outpatient settings?

A. Malignancy
B. Primary hyperparathyroidism (Correct Answer)
C. Vitamin D toxicity
D. Thiazide diuretics

Explanation: **Primary hyperparathyroidism** - Accounts for the majority of hypercalcemia cases in **outpatient settings** (up to 90%). [1] - It is characterized by the **excessive secretion of parathyroid hormone (PTH)** from one or more parathyroid glands, leading to increased serum calcium levels. [1], [2] *Malignancy* - While it is the most common cause of hypercalcemia in **inpatient settings**, it is less frequent than primary hyperparathyroidism in outpatients. [1] - Often associated with **parathyroid hormone-related peptide (PTHrP)** secretion or bone metastases. [1] *Vitamin D toxicity* - This is a rare cause of hypercalcemia, usually resulting from **excessive supplementation** or medication error. [1] - It leads to increased intestinal calcium absorption and bone resorption, but is not as common as primary hyperparathyroidism. *Thiazide diuretics* - These medications can cause **mild hypercalcemia** by increasing renal calcium reabsorption. [1] - However, the hypercalcemia is typically mild and rarely as significant as that seen in primary hyperparathyroidism or malignancy.

Question 1653: Which of the following is the most prominent clinical manifestation of primary hyperaldosteronism (Conn's syndrome)?

A. Hyperkalemia
B. Hypertension (Correct Answer)
C. Hypokalemia
D. Expansion of Extracellular and Plasma volume

Explanation: ** Hypertension** - **Hypertension** is the most prominent and consistent clinical manifestation of primary hyperaldosteronism, present in nearly all patients. - The excessive aldosterone leads to increased **sodium reabsorption** and water retention, directly causing elevated blood pressure [2], [3]. *Hypokalemia* - While **hypokalemia** is common in primary hyperaldosteronism due to increased renal potassium excretion, it is not universally present and can be absent in a significant portion of patients (up to 30-50%). - Therefore, hypertension is a more reliable and prominent symptom for initial suspicion [3]. *Hyperkalemia* - **Hyperkalemia** is inconsistent with primary hyperaldosteronism; the hallmark of the condition is **potassium wasting** and **hypokalemia**, not elevated potassium levels [2]. - Aldosterone's primary role includes promoting potassium excretion, so hyperkalemia would indicate a different underlying pathology, such as adrenal insufficiency [2]. *Expansion of Extracellular and Plasma volume* - While increased aldosterone does lead to **expansion of extracellular and plasma volume** due to sodium and water retention, this is a physiological consequence that contributes to hypertension rather than being the most prominent *clinical manifestation* itself [1]. - Hypertension is the direct observable and measurable clinical symptom that drives investigation [3].

Question 1654: A 45-year-old woman presents with increased testosterone levels and temporal hair recession. What is the most likely diagnosis?

A. Osteoporosis
B. Rheumatoid arthritis
C. Granulosa theca cell tumour
D. Polycystic Ovary Syndrome (PCOS) (Correct Answer)

Explanation: Polycystic Ovary Syndrome (PCOS) - PCOS is characterized by hormonal imbalances, leading to elevated androgen (testosterone) levels, which can cause symptoms like hirsutism (excess body hair), acne, and temporal hair recession in women [1]. - The elevated testosterone levels directly explain the temporal hair recession, which is a common manifestation of androgen excess in PCOS [1]. Osteoporosis - Osteoporosis is a condition of decreased bone density and increased fracture risk. - It is primarily related to estrogen deficiency and typically does not involve increased testosterone levels or temporal hair recession. Rheumatoid arthritis - Rheumatoid arthritis is an autoimmune inflammatory disease primarily affecting the joints. - It does not cause increased testosterone levels or temporal hair recession. Granulosa theca cell tumour - While granulosa cell tumors can produce hormones, they are more commonly associated with estrogen production and present with symptoms like abnormal uterine bleeding. - Although theca cell tumors can produce androgens, they are rare and typically present with more severe and rapid onset of virilization compared to the chronic presentation implied by the question [1].

Question 1655: Bones, stones, abdominal groans, and psychiatric overtones are features of?

A. Hypothyroidism
B. Hyperparathyroidism (Correct Answer)
C. Hypoparathyroidism
D. Hyperthyroidism

Explanation: ***Hyperparathyroidism*** - This mnemonic ("**bones, stones, abdominal groans, and psychiatric overtones**") perfectly describes the classic manifestations of **hypercalcemia** due to hyperparathyroidism [1]. - **Bones** refers to bone pain from increased osteoclastic activity [1], **stones** to kidney stones [1], **abdominal groans** to GI symptoms like constipation or pancreatitis [1], and **psychiatric overtones** to neuropsychiatric symptoms like depression or confusion. *Hyperthyroidism* - Characterized by symptoms of an **overactive metabolism**, such as weight loss, heat intolerance, tremor, and tachycardia [1]. - It does not typically present with the "bones, stones, and groans" triad associated with calcium imbalances. *Hypothyroidism* - Involves symptoms of an **underactive metabolism**, including weight gain, cold intolerance, fatigue, and bradycardia. - While it can cause some psychiatric symptoms (e.g., depression), it does not involve issues like kidney stones or significant bone problems from hypercalcemia. *Hypoparathyroidism* - Leads to **hypocalcemia**, presenting with symptoms like **tetany**, muscle cramps, paresthesias, and seizures. - This is the opposite of hyperparathyroidism and would not cause the symptoms listed in the mnemonic.

Question 1656: Which of the following conditions is least likely to be associated with diabetes mellitus?

A. Noonan syndrome
B. Ataxia telengiectasia
C. Fanconi syndrome (Correct Answer)
D. Myotonic dystrophy

Explanation: ***Fanconi syndrome*** - This syndrome primarily involves a generalized defect in **proximal renal tubular function**, leading to excessive excretion of glucose, amino acids, phosphate, and bicarbonate. - While it can be inherited or acquired, it is **not directly linked** to the pathogenesis or common complications of diabetes mellitus. *Noonan syndrome* - Individuals with Noonan syndrome are at an **increased risk of developing diabetes mellitus**, often due to insulin resistance and impaired glucose tolerance. - This genetic disorder, characterized by distinctive facial features, short stature, and cardiac defects, includes **endocrine abnormalities** that predispose to metabolic dysfunction. *Ataxia telangiectasia* - This rare, **autosomal recessive immune deficiency disorder** is associated with an increased incidence of diabetes mellitus [1]. - Patients often present with **insulin resistance** and impaired glucose homeostasis, making diabetes a recognized comorbidity [2]. *Myotonic dystrophy* - Myotonic dystrophy, particularly type 1, is frequently associated with **endocrine abnormalities**, including a high prevalence of **insulin resistance** and impaired glucose tolerance, often progressing to diabetes mellitus [2]. - This inherited neuromuscular disorder can manifest with a variety of systemic complications, with diabetes being a common one.

Question 1657: Nelson's syndrome is most likely seen after removal of both adrenal glands.

A. Hypophysectomy
B. Adrenalectomy (Correct Answer)
C. Thyroidectomy
D. Orchidectomy

Explanation: ***Adrenalectomy*** - Nelson's syndrome develops in some patients following bilateral **adrenalectomy** performed for **Cushing's disease**. - The removal of the adrenal glands leads to a loss of negative feedback on the pituitary, causing uncontrolled growth of a pre-existing **corticotroph adenoma** and increased **ACTH** production. *Hypophysectomy* - **Hypophysectomy** is the surgical removal of the **pituitary gland**, which would prevent the development of Nelson's syndrome as it removes the source of ACTH. - This procedure is a treatment for Cushing's disease, but Nelson's syndrome occurs *after* adrenalectomy, not hypophysectomy. *Thyroidectomy* - **Thyroidectomy** is the removal of all or part of the **thyroid gland** and is unrelated to adrenal or pituitary dysfunction. - This procedure is typically performed for conditions like thyroid cancer, hyperthyroidism, or large goiters. *Orchidectomy* - **Orchidectomy** is the surgical removal of one or both **testes**. - This procedure is primarily used in the treatment of testicular cancer or for hormonal therapy in prostate cancer and has no connection to Nelson's syndrome.

Question 1658: For differentiating between insulinoma and sulfonylurea-related hypoglycemia, which test is most useful?

A. Insulin:glucose ratio
B. Plasma insulin level
C. Antibody to insulin
D. Plasma C-peptide level (Correct Answer)

Explanation: Detailed testing is required to distinguish sources of hypoglycemia. Plasma C-peptide level: A high C-peptide level despite hypoglycemia suggests endogenous insulin secretion, as seen in insulinoma [1]. In sulfonylurea-induced hypoglycemia, a high C-peptide would also be seen because sulfonylureas stimulate endogenous insulin release from beta cells [2]. However, in an exogenous insulin injection, it would be low. Antibody to insulin: Antibody to insulin is primarily used to detect exogenous insulin administration due to an immune response. While it might be present in rare cases of autoimmune hypoglycemia, it is not the primary diagnostic tool to differentiate between these two conditions. Plasma insulin level: Both insulinoma and sulfonylurea use lead to elevated plasma insulin levels during hypoglycemia, as both involve increased insulin activity [1]. Therefore, insulin levels alone would not help distinguish between these two causes of hypoglycemia. Insulin:glucose ratio: The insulin:glucose ratio would be elevated in both insulinoma and sulfonylurea-induced hypoglycemia. This ratio indicates an inappropriately high level of insulin for the given glucose concentration, but it does not differentiate between endogenous overproduction and sulfonylurea stimulation.

Question 1659: The endocrine disorder associated with generalized lymphadenopathy is?

A. Addison's disease
B. Carcinoid syndrome
C. Hyperthyroidism (Correct Answer)
D. Cushing's syndrome

Explanation: ***Hyperthyroidism*** - **Generalized lymphadenopathy** can be a clinical manifestation of **hyperthyroidism**, particularly in conditions like **Graves' disease** [1]. - This is thought to be due to **immunological overactivity** often associated with autoimmune thyroid conditions [2]. *Addison's disease* - **Addison's disease** is characterized by **adrenal insufficiency** and typically presents with symptoms like **fatigue**, **skin hyperpigmentation**, and **hypotension**. - It is not commonly associated with **generalized lymphadenopathy**. *Cushing's syndrome* - **Cushing's syndrome** results from **prolonged exposure to high levels of cortisol**, leading to symptoms like **central obesity**, **moon facies**, and **hirsutism**. - **Lymphadenopathy** is not a feature of **Cushing's syndrome**; in fact, chronic cortisol excess can cause **lymphopenia**. *Carcinoid syndrome* - **Carcinoid syndrome** is caused by **neuroendocrine tumors** secreting **vasoactive substances** like serotonin, leading to symptoms such as **flushing**, **diarrhea**, and **bronchospasm**. - **Lymphadenopathy** is not typically part of the carcinoid syndrome, although tumor metastasis to lymph nodes can occur.

Question 1660: Osteitis fibrosa cystica is associated with which of the following conditions?

A. Hyperparathyroidism (Correct Answer)
B. Hypoparathyroidism
C. Hypothyroidism
D. Hyperthyroidism

Explanation: ***Hyperparathyroidism*** - **Osteitis fibrosa cystica** is a classic bone manifestation of severe, chronic **hyperparathyroidism**, characterized by increased osteoclastic activity. - This condition results in the replacement of normal bone with **fibrous tissue** and **cysts**, often leading to bone pain, fractures, and deformities. *Hypoparathyroidism* - **Hypoparathyroidism** is characterized by low parathyroid hormone (PTH) levels and **hypocalcemia**, which typically leads to increased bone density, not bone degradation. - Its manifestations include muscle cramps, seizures, and tetany, without the bone lesions seen in osteitis fibrosa cystica. *Hypothyroidism* - **Hypothyroidism** is a state of thyroid hormone deficiency, affecting metabolism and growth but not directly causing osteitis fibrosa cystica. - It can lead to slowed bone turnover and delayed growth in children, but not the specific bone lesions associated with parathyroid dysfunction. *Hyperthyroidism* - **Hyperthyroidism** can cause increased bone turnover and **osteoporosis** due to accelerated bone resorption, but it does not lead to the distinct fibrous and cystic bone changes of osteitis fibrosa cystica. - Its effects on bone are generally a diffuse reduction in bone mineral density rather than specific lytic lesions or brown tumors.

Practice by Chapter

Diabetes Mellitus

Practice Questions

Thyroid Disorders

Practice Questions

Adrenal Gland Disorders

Practice Questions

Pituitary Disorders

Practice Questions

Calcium and Bone Metabolism

Practice Questions

Reproductive Endocrinology

Practice Questions

Lipid Disorders

Practice Questions

Endocrine Hypertension

Practice Questions

Multiple Endocrine Neoplasia

Practice Questions

Obesity and Metabolic Syndrome

Practice Questions

Neuroendocrine Tumors

Practice Questions

Endocrine Emergencies

Practice Questions

Want unlimited practice?

Get full access to all questions, explanations, and performance tracking.

Start For Free