Endocrinology Practice Questions

Q: A patient presents with galactorrhea and visual defects. Which investigation should be performed?

MRI. **Explanation:** The clinical presentation of **galactorrhea** combined with **visual field defects** (typically bitemporal hemianopia) strongly suggests a **pituitary adenoma** (most likely a Prolactinoma) [1]. Large tumors (macroadenomas >10mm) compress the optic chiasm, leading to visual impairment [1]. 1. **Why MRI is the Correct Answer:** **MRI with gadolinium enhancement** is the gold standard and investigation of choice for visualizing the pituitary gland and the sella turcica [1]. It provides superior soft-tissue resolution compared to CT, allowing for the precise identification of microadenomas (<10mm), macroadenomas, and their relationship to surrounding structures like the optic chiasm and cavernous sinuses [1]. 2. **Why other options are incorrect:** * **Serum Prolactin:** While this is the initial *biochemical* test to confirm hyperprolactinemia, it cannot visualize the anatomical extent of the tumor or the cause of the visual defect [1]. * **CT Scan:** CT is less sensitive than MRI for pituitary lesions and provides poor visualization of the optic chiasm. * **Angiography:** This is an invasive procedure used for vascular pathologies (like aneurysms) and has no role in the routine workup of a suspected pituitary adenoma. **NEET-PG High-Yield Pearls:** * **Investigation of choice for Pituitary lesions:** MRI [1]. * **Most common secretory pituitary tumor:** Prolactinoma. * **Medical Management:** Dopamine agonists (Cabergoline is preferred over Bromocriptine due to better efficacy and fewer side effects) [1]. * **Surgical Indication:** If the patient has visual field defects or is refractory to medical therapy (Transsphenoidal surgery) [1].

Q: A 65-year-old woman presents with low mood. Her past medical history includes atrial fibrillation and type 2 diabetes. Clinical examination reveals cool peripheries and a pulse of 45 bpm. Thyroid function tests show TSH: 6.5 mU/L and T4: 4 pmol/L. Which of the following is the most likely cause of this patient's symptoms?

Drug-induced hypothyroidism. ### Explanation **1. Why Drug-induced Hypothyroidism is correct:** The patient presents with classic symptoms of hypothyroidism (low mood, cool peripheries, bradycardia) and biochemical evidence of primary hypothyroidism (High TSH, Low T4). The crucial clue lies in her history of **atrial fibrillation**. **Amiodarone**, a commonly used Class III antiarrhythmic for AFib, contains 37% iodine by weight. It can induce hypothyroidism via the **Wolff-Chaikoff effect** (excess iodine inhibiting thyroid hormone synthesis) [1]. Given the clinical context of AFib, amiodarone-induced hypothyroidism is the most likely diagnosis [1]. **2. Why the other options are incorrect:** * **Hashimoto’s Thyroiditis:** While the most common cause of primary hypothyroidism, it typically presents with much higher TSH levels (often >10 mU/L) and wouldn't specifically link to a history of atrial fibrillation as strongly as a drug-induced cause in this scenario. * **Secondary/Tertiary Hypothyroidism:** These refer to central hypothyroidism (pituitary or hypothalamic failure). In these cases, the **TSH would be low or inappropriately normal** in the presence of a low T4. This patient has an elevated TSH (6.5 mU/L), which localizes the pathology to the thyroid gland itself (Primary). **3. NEET-PG High-Yield Pearls:** * **Amiodarone & Thyroid:** It can cause both hypothyroidism (Wolff-Chaikoff) and hyperthyroidism (Jod-Basedow effect or destructive thyroiditis) [1]. * **Wolff-Chaikoff Effect:** A protective autoregulatory phenomenon where high iodine levels inhibit thyroperoxidase, decreasing T3/T4 production. * **Lithium:** Another high-yield drug causing hypothyroidism by inhibiting thyroid hormone release. * **Subclinical Hypothyroidism:** Defined as elevated TSH with **normal** T4. This patient has **overt** hypothyroidism because her T4 is low.

Q: Which of the following conditions is associated with pituitary adenoma?

Multiple Endocrine Neoplasia type 4 (MEN4). **Explanation:** The correct answer is **Multiple Endocrine Neoplasia type 4 (MEN4)**. **1. Why MEN4 is correct:** MEN4 is a rare autosomal dominant syndrome caused by a germline mutation in the **CDKN1B gene** (encoding the p27 protein), which acts as a cyclin-dependent kinase inhibitor. Clinically, MEN4 presents very similarly to MEN1. It is characterized by a "3P" pattern, though with lower penetrance: **Pituitary adenomas**, **Parathyroid adenomas**, and **Pancreatic neuroendocrine tumors**. Therefore, pituitary adenoma is a hallmark feature of this condition. **2. Why the other options are incorrect:** * **MEN2A:** Caused by **RET proto-oncogene** mutations. It is characterized by the "MPH" triad: Medullary thyroid carcinoma (MTC), Pheochromocytoma, and Hyperparathyroidism. It does **not** involve the pituitary gland. * **MEN2B (formerly MEN3):** Also caused by RET mutations. It presents with MTC, Pheochromocytoma, and mucosal neuromas/Marfanoid habitus. Pituitary adenomas are not part of this syndrome. * **MEN3:** This is an older nomenclature for MEN2B and is no longer used as a separate category in modern classification. **3. NEET-PG High-Yield Pearls:** * **MEN1 (Wermer Syndrome):** The classic "3Ps" (Pituitary, Parathyroid, Pancreas). Caused by the *MEN1* gene (Menin). * **MEN4:** Think of it as "MEN1-like" but caused by *CDKN1B*. * **Pituitary involvement:** Only seen in **MEN1** and **MEN4**. * **Medullary Thyroid Carcinoma:** Present in 100% of MEN2A and 2B cases; prophylactic thyroidectomy is often indicated. * **Most common pituitary tumor in MEN1/4:** Prolactinoma.

Q: Which of the following could develop with a mucosal neuroma on the lower lip, a family history of medullary thyroid carcinoma, and recent introduction of severe headaches, perspiration, palpitations, and hypertension?

Pheochromocytoma. ### Explanation The clinical presentation described is classic for **Multiple Endocrine Neoplasia Type 2B (MEN 2B)**. This autosomal dominant syndrome, caused by a mutation in the **RET proto-oncogene**, is characterized by a triad of: 1. **Medullary Thyroid Carcinoma (MTC):** Often aggressive and occurs early in life (explaining the family history). 2. **Pheochromocytoma:** Occurs in approximately 50% of cases. 3. **Mucosal Neuromas:** Typically found on the tongue, lips (as seen here), and eyelids, often accompanied by a **Marfanoid habitus**. The patient’s "recent introduction" of severe headaches, perspiration, palpitations, and hypertension forms the classic **"PHE" triad** (Palpitations, Headache, Episodic sweating), which is pathognomonic for a **Pheochromocytoma** (Option D). #### Analysis of Incorrect Options: * **A & B (Gastrinoma/Insulinoma):** These are Pancreatic Neuroendocrine Tumors (NETs) [1], which are components of **MEN 1** (the "3 Ps": Pituitary, Parathyroid, Pancreas), not MEN 2B. Insulinomas are confirmed as a pancreatic NET associated with hormone excess syndromes [3]. * **C (Parathyroid Adenoma):** While parathyroid hyperplasia/adenoma is a key feature of **MEN 1** and **MEN 2A**, it is characteristically **characteristically absent** in MEN 2B. #### NEET-PG High-Yield Pearls: * **MEN 2A (Sipple Syndrome):** MTC + Pheochromocytoma + Parathyroid Hyperplasia. * **MEN 2B (Wagenmann–Froboese Syndrome):** MTC + Pheochromocytoma + Mucosal Neuromas/Marfanoid habitus. * **Rule of 10s for Pheochromocytoma:** 10% bilateral, 10% malignant, 10% extra-adrenal, 10% pediatric, and 10% familial [2]. * **Clinical Priority:** In any MEN 2 patient, always screen for and surgically remove a Pheochromocytoma **before** addressing the thyroid to prevent a lethal hypertensive crisis during anesthesia [2].

Question 1

A patient presents with galactorrhea and visual defects. Which investigation should be performed?

Accepted Answer

MRI

Answer

Serum prolactin

Answer

CT scan of the brain

Answer

Angiography

Question 2

A 65-year-old woman presents with low mood. Her past medical history includes atrial fibrillation and type 2 diabetes. Clinical examination reveals cool peripheries and a pulse of 45 bpm. Thyroid function tests show TSH: 6.5 mU/L and T4: 4 pmol/L. Which of the following is the most likely cause of this patient's symptoms?

Accepted Answer

Drug-induced hypothyroidism

Answer

Hashimoto's thyroiditis

Answer

Secondary hypothyroidism

Answer

Tertiary hypothyroidism

Question 3

When galactorrhea occurs in a high school student, which of the following is an associated diagnostic finding?

Accepted Answer

Bitemporal hemianopia

Answer

Gonadal atrophy

Answer

Exophthalmos and lid lag

Answer

Episodic hypertension

Question 4

A 25-year-old young lady presented with a complaint of acute hirsutism and hoarseness of voice. Which of the following is the best investigation for diagnosis?

Accepted Answer

Blood DHEA levels

Answer

Blood pregnenolone levels

Answer

17-ketosteroids level

Answer

LH and FSH levels

Question 5

Which of the following conditions is associated with pituitary adenoma?

Accepted Answer

Multiple Endocrine Neoplasia type 4 (MEN4)

Answer

Multiple Endocrine Neoplasia type 2A (MEN2A)

Answer

Multiple Endocrine Neoplasia type 2B (MEN2B)

Answer

Multiple Endocrine Neoplasia type 3 (MEN3)

Question 6

Which of the following could develop with a mucosal neuroma on the lower lip, a family history of medullary thyroid carcinoma, and recent introduction of severe headaches, perspiration, palpitations, and hypertension?

Accepted Answer

Pheochromocytoma

Answer

Gastrinoma

Answer

Insulinoma

Answer

Parathyroid adenoma

Question 7

Which of the following is NOT a feature of glucocorticoid deficiency?

Accepted Answer

Hyperkalemia

Answer

Hyponatremia

Answer

Hypoglycemia

Answer

Fever

Question 8

A hypertensive primigravida developed Sheehan's syndrome after delivery. All of the following are seen with Sheehan's syndrome, EXCEPT?

Accepted Answer

Obesity

Answer

Amenorrhoea

Answer

Failure to lactate

Answer

Absence of secondary sexual characteristics

Question 9

Brown tumors, compression syndromes, and erythropoietin resistance are seen in which condition?

Accepted Answer

Hyperparathyroidism

Answer

Hypothyroidism

Answer

Hyperthyroidism

Answer

Osteoporosis

Question 10

A 41-year-old man presented with a 9-month history of cough, exertional dyspnea, nocturnal diaphoresis, and weight loss of 10 kg. Physical examination revealed painless, massive, discrete, rubbery cervical, supraclavicular, and axillary lymphadenopathy. Chest radiography showed bilateral hilar lymphadenopathy. The serum calcium level was elevated at 16.2 mg/dL, with serum parathyroid hormone within the normal range. What is the urgent treatment to be instituted?

Accepted Answer

Intravenous administration of normal saline and a bisphosphonate

Answer

Oxygen 6 L/min by mask

Answer

Antibiotics and anti-inflammatory drugs

Answer

Antitussive and chest physiotherapy

Endocrinology — MCQs

Endocrinology — MCQs

On this page

Practice by Chapter

Want unlimited practice?