Endocrinology & Diabetes — MCQs

A 26-year-old woman with type 1 diabetes is planning pregnancy. She currently uses insulin degludec 28 units at night and insulin aspart with meals. Her HbA1c is 58 mmol/mol (7.5%). She takes no other regular medications. What additional medication should be commenced before conception and continued until at least 12 weeks gestation?

Q48

A 55-year-old woman undergoes total thyroidectomy for a 4.5cm papillary thyroid carcinoma with lymph node involvement. Histology confirms papillary carcinoma with extrathyroidal extension and 3 out of 8 lymph nodes positive. Post-operatively, she is started on levothyroxine 100 micrograms once daily. What is the target TSH level for this patient in the first year following surgery?

Q49

A 65-year-old man with type 2 diabetes for 12 years on metformin and empagliflozin presents for annual review. His eGFR has declined from 54 mL/min/1.73m² one year ago to 28 mL/min/1.73m² currently. Urine albumin:creatinine ratio is 42 mg/mmol. Blood pressure is 142/88 mmHg. He is taking ramipril 10mg once daily. HbA1c is 64 mmol/mol (8.0%). What is the most appropriate modification to his diabetes management?

Q50

A 37-year-old woman presents with anxiety, palpitations, and heat intolerance. Examination reveals a smooth, non-tender goitre and a resting tremor. Thyroid function shows TSH <0.01 mU/L, free T4 38 pmol/L, free T3 16.4 pmol/L. TSH receptor antibodies are strongly positive. She is started on carbimazole 40mg once daily. After 6 weeks, she develops a sore throat and fever. Blood tests show: Hb 118 g/L, WCC 1.8 × 10⁹/L, neutrophils 0.4 × 10⁹/L, platelets 242 × 10⁹/L. What is the most appropriate immediate management?

Endocrinology & Diabetes UK Medical PG Practice Questions and MCQs

Question 41: A 52-year-old woman presents with recurrent episodes of severe flushing and diarrhea. CT shows multiple liver lesions and a small bowel mass. 24-hour urine 5-HIAA is elevated. What is the most appropriate initial treatment?

A. Octreotide (Correct Answer)
B. Surgical resection
C. Chemotherapy
D. Radiotherapy
E. Liver transplantation

Explanation: ***Octreotide*** - The patient's presentation with **recurrent flushing**, **diarrhea**, **multiple liver lesions**, a **small bowel mass**, and **elevated 24-hour urine 5-HIAA** strongly suggests **carcinoid syndrome**. - **Somatostatin analogs** like **octreotide** are the **first-line medical treatment** for symptomatic carcinoid syndrome, effectively controlling hormone release (e.g., serotonin) and alleviating symptoms. *Surgical resection* - While **surgical debulking** of the primary tumor and liver metastases can be considered, particularly for symptom control or local complications, it is often not the initial treatment for symptomatic, metastatic carcinoid syndrome due to its invasiveness. - The immediate priority is typically symptom management with medical therapy, especially in the presence of widespread disease indicated by multiple liver lesions. *Chemotherapy* - **Chemotherapy** is generally reserved for **poorly differentiated neuroendocrine tumors** or those with rapid progression and high tumor burden. - Well-differentiated neuroendocrine tumors causing carcinoid syndrome often respond poorly to conventional chemotherapy, making it a less preferred initial approach compared to somatostatin analogs. *Radiotherapy* - **Radiotherapy** is primarily used for **localized disease control**, such as managing bone metastases or specific painful lesions, and is not a systemic treatment for carcinoid syndrome or its endocrine symptoms. - It does not effectively address the systemic release of hormones responsible for flushing and diarrhea. *Liver transplantation* - **Liver transplantation** is an aggressive and highly selective option considered only for patients with **limited liver metastatic disease** and no other extrahepatic spread, aiming for potential cure in very specific cases. - It is not an initial treatment for symptom control in a patient presenting with symptomatic metastatic carcinoid syndrome.

Question 42: A 41-year-old woman presents with recurrent kidney stones and bone pain. Serum calcium is 2.9 mmol/L, phosphate 0.7 mmol/L, PTH 85 pg/mL (elevated). What is the most likely diagnosis?

A. Primary hyperparathyroidism (Correct Answer)
B. Secondary hyperparathyroidism
C. Tertiary hyperparathyroidism
D. Sarcoidosis
E. Malignancy

Explanation: ***Primary hyperparathyroidism***- High serum **calcium** (2.9 mmol/L) and an inappropriately high **parathyroid hormone (PTH)** (85 pg/mL) confirm this diagnosis, as PTH should be suppressed in response to hypercalcemia.- Clinical features like recurrent **kidney stones** (due to hypercalciuria) and **bone pain** are classic manifestations, supporting this diagnosis.*Secondary hyperparathyroidism*- This condition is characterized by high PTH levels occurring as a physiological response to long-standing **hypocalcemia**, typically due to **Vitamin D deficiency** or **Chronic Kidney Disease**.- The patient exhibits significant **hypercalcemia**, which inherently rules out secondary hyperparathyroidism as an initial diagnosis.*Tertiary hyperparathyroidism*- This occurs when parathyroid glands become autonomous after prolonged **secondary hyperparathyroidism**, usually in the setting of **end-stage renal disease**.- While tertiary hyperparathyroidism can present with high PTH and hypercalcemia, in a patient without a clear history of chronic kidney disease, primary hyperparathyroidism is the more likely initial cause.*Sarcoidosis*- Sarcoidosis causes hypercalcemia due to the ectopic production of **1,25-dihydroxyvitamin D** by activated macrophages.- This excess vitamin D promotes intestinal calcium absorption which leads to suppression of the normal **PTH** levels (PTH would be low or undetectable).*Malignancy*- Malignancy-induced hypercalcemia (often due to **PTH-related peptide [PTHrP]**) acts like PTH but causes suppression of the true intrinsic **PTH** level.- Hypercalcemia due to bone metastases also suppresses PTH, which is contradictory to this patient's elevated PTH level.

Question 43: A 42-year-old woman presents with fatigue, muscle weakness, and hyperpigmentation of her palmar creases and buccal mucosa. Blood pressure is 95/60 mmHg. Na+ 128 mmol/L, K+ 5.2 mmol/L. What is the most likely diagnosis?

A. Addison's disease (Correct Answer)
B. Cushing's syndrome
C. Conn's syndrome
D. Hypothyroidism
E. Chronic kidney disease

Explanation: ***Addison's disease*** - The constellation of **hyperpigmentation** (due to high **ACTH** stimulating melanocytes), profound fatigue, muscle weakness, and **hypotension** is classic for primary adrenal insufficiency. - The electrolyte imbalances—**hyponatremia** (salt wasting due to mineralocorticoid deficiency) and **hyperkalemia** (lack of aldosterone action)—further confirm this diagnosis. *Cushing's syndrome* - This condition involves **glucocorticoid excess** and typically presents with centripetal obesity, striae, and **hypertension**, not hypotension. - Electrolytes often show **hypokalemia** (due to cortisol's weak mineralocorticoid effects) and normal or elevated sodium, not hyperkalemia or severe hyponatremia. *Conn's syndrome* - This is **primary hyperaldosteronism**, characterized by excessive mineralocorticoid activity. - Features include **severe hypertension** and **hypokalemia** (due to potassium wasting), which are the opposite of this patient's electrolytes and blood pressure. *Hypothyroidism* - While causing fatigue, typical signs include **weight gain**, cold intolerance, and **bradycardia**. - It does not cause the specific pattern of profound hypotension, hyperkalemia, or **ACTH-driven hyperpigmentation**. *Chronic kidney disease* - CKD can cause fatigue, hyperkalemia, and hyponatremia, but usually presents with signs of uremia and requires elevated creatinine/BUN. - The prominent **hyperpigmentation** in the palmar creases is a specific sign of primary adrenal failure due to high ACTH, which is not a defining feature of isolated CKD.

Question 44: A 35-year-old man presents with recurrent episodes of severe sweating, palpitations, and headache lasting 15-20 minutes. His BP during an episode is 220/130 mmHg. 24-hour urine catecholamines are elevated. What is the most likely diagnosis?

A. Essential hypertension
B. Pheochromocytoma (Correct Answer)
C. Panic disorder
D. Hyperthyroidism
E. Renal artery stenosis

Explanation: ***Pheochromocytoma***- The classic triad of **paroxysmal headache**, **sweating**, and **palpitations** along with severe **hypertension** (220/130 mmHg) are hallmark clinical features.- The diagnosis is confirmed by significantly elevated **24-hour urine catecholamines**, indicating excessive secretion from this adrenal medullary tumor.*Essential hypertension*- This condition typically presents with a **sustained, stable elevation** in blood pressure, not severe, short-lived **paroxysmal hypertensive crises**.- Essential hypertension is a diagnosis of exclusion and would not be associated with a classic symptom triad or markedly elevated **catecholamine** levels.*Panic disorder*- While panic attacks can cause palpitations and sweating, they rarely induce blood pressure readings as dramatically high as **220/130 mmHg**.- Panic disorder is a psychiatric condition and would not lead to significantly increased **24-hour urinary catecholamine** levels.*Hyperthyroidism*- This condition causes **sustained symptoms** (e.g., tachycardia, weight loss, heat intolerance), not acute paroxysmal crises.- While it can cause sympathetic hyperactivity, it would not result in the marked, episodic surges of **catecholamines** diagnostic of a pheochromocytoma, and hypertension is often predominantly **systolic**.*Renal artery stenosis*- This causes sustained secondary hypertension due to activation of the **renin-angiotensin-aldosterone system** (RAAS).- It is not associated with the paroxysmal triad (sweating, palpitations, headache) and would not result in elevated urinary **catecholamines**.

Question 45: A 24-year-old woman presents with amenorrhea, galactorrhea, and bitemporal visual field defects. MRI shows a 2cm pituitary mass. Prolactin level is 8000 mU/L. What is the most appropriate initial treatment?

A. Transsphenoidal surgery
B. Radiotherapy
C. Cabergoline (Correct Answer)
D. Bromocriptine
E. Octreotide

Explanation: ***Cabergoline***- **Cabergoline** is the preferred first-line medical treatment for **prolactinomas** (both micro- and macroprolactinomas) due to its high efficacy in normalizing prolactin levels and shrinking tumor size.- It is a long-acting **dopamine agonist** that effectively treats the symptoms (amenorrhea, galactorrhea) and reverses mass effects (**bitemporal visual field defects**) by causing significant tumor shrinkage.*Transsphenoidal surgery*- Surgery is typically reserved for tumors resistant to the maximal dose of **dopamine agonists** or for patients who cannot tolerate medical therapy.- Surgical intervention is also considered for patients presenting with **acute apoplexy** or significant visual loss that is unresponsive to a short trial of high-dose dopamine agonists.*Radiotherapy*- This is a tertiary modality, generally considered only for **aggressive** or **non-resectable tumors** that fail to respond to maximal doses of dopamine agonists and surgical intervention.- It carries risks of delayed effects, including **hypopituitarism**, and is rarely used as primary treatment for prolactinomas.*Bromocriptine*- While also a **dopamine agonist** effective for prolactinomas, **Cabergoline** is superior as a true first-line treatment due to its twice-weekly dosing (better compliance) and lower incidence of **gastrointestinal side effects**.- **Bromocriptine** is usually reserved for patients who do not tolerate or who cannot access cabergoline.*Octreotide*- **Octreotide** is a **somatostatin analog** used primarily in the treatment of **acromegaly** (growth hormone-secreting tumors) and **TSH-secreting tumors**.- It does not effectively reduce prolactin levels, making it ineffective for the primary management of a **prolactinoma**.

Question 46: A 43-year-old woman presents with a 6-month history of weight gain, purple striae, and proximal muscle weakness. Her blood glucose is elevated and she has developed hypertension. 24-hour urine cortisol is raised. What is the most appropriate initial investigation?

A. MRI pituitary
B. Dexamethasone suppression test (Correct Answer)
C. ACTH levels
D. Adrenal CT
E. Midnight salivary cortisol

Explanation: ***Dexamethasone suppression test***- The constellation of symptoms (**weight gain**, **purple striae**, **proximal muscle weakness**, **hypertension**, **elevated glucose**), along with a raised 24-hour urine cortisol (UFC), strongly suggests **hypercortisolism** (Cushing's syndrome).- The **Low-Dose Dexamethasone Suppression Test** (LDDST) is the gold standard for biochemically confirming Cushing's syndrome, demonstrating the loss of normal cortisol feedback regulation.*MRI pituitary*- This test is a **localization study** used to identify a pituitary adenoma (Cushing's disease) and is only warranted after the biochemical diagnosis of Cushing's syndrome is confirmed and categorized as **ACTH-dependent**.- Performing an MRI before confirming the diagnosis and ACTH dependency can lead to unnecessary imaging or misinterpretation of incidental findings.*ACTH levels*- Measuring **ACTH levels** is the crucial next step *after* confirming hypercortisolism to differentiate between **ACTH-dependent** and **ACTH-independent** causes of Cushing's syndrome.- However, the initial step following screening (raised 24-hour UFC) is to confirm true pathological hypercortisolism with a dynamic test like the LDDST.*Adrenal CT*- A CT of the adrenals is a **localization study** indicated when ACTH levels are low, suggesting an **ACTH-independent** cause (e.g., primary adrenal adenoma or carcinoma).- It is inappropriate to proceed directly to imaging without biochemical confirmation and etiological classification, as this risks missing the true cause or performing unnecessary tests.*Midnight salivary cortisol*- This test is primarily used as a **screening test** for endogenous hypercortisolism, often in conjunction with 24-hour UFC and LDDST.- Since the 24-hour UFC is already raised, indicating probable hypercortisolism, a further screening test is less informative than the LDDST, which directly assesses the feedback mechanism essential for diagnosis.

Question 47: A 26-year-old woman with type 1 diabetes is planning pregnancy. She currently uses insulin degludec 28 units at night and insulin aspart with meals. Her HbA1c is 58 mmol/mol (7.5%). She takes no other regular medications. What additional medication should be commenced before conception and continued until at least 12 weeks gestation?

A. Folic acid 400 micrograms daily
B. Folic acid 5mg daily (Correct Answer)
C. Aspirin 75mg daily
D. Aspirin 150mg daily
E. Vitamin D 400 units daily

Explanation: ***Folic acid 5mg daily*** - Women with **diabetes mellitus** (Type 1 or Type 2) are at a higher risk of **neural tube defects** and require a high-dose supplementation of **5mg folic acid**. - This dose should be started **pre-conception** and continued until **12 weeks gestation** to optimize fetal spinal cord development.*Folic acid 400 micrograms daily* - This is the standard dose for the **general population** but is insufficient for high-risk groups like those with diabetes or a high BMI. - Using this lower dose in a diabetic patient increases the relative risk of **congenital malformations** compared to the high-dose regimen.*Aspirin 75mg daily* - Low-dose aspirin is used to reduce the risk of **pre-eclampsia**, but the standard recommended dose for high-risk patients has shifted toward **150mg**. - Crucially, aspirin is initiated from **12 weeks gestation** until birth, rather than during the pre-conception period.*Aspirin 150mg daily* - While **150mg aspirin** is indicated for diabetic pregnant women to prevent **pre-eclampsia**, it is not the medication started pre-conception. - The protocol specifies starting this medication in the **second trimester** (from 12 weeks), not before pregnancy.*Vitamin D 400 units daily* - General supplementation of **Vitamin D** is recommended for all pregnant and breastfeeding women to support **bone health**. - While beneficial, it is not the priority medication specifically indicated to mitigate the high risk of **neural tube defects** associated with diabetes.

Question 48: A 55-year-old woman undergoes total thyroidectomy for a 4.5cm papillary thyroid carcinoma with lymph node involvement. Histology confirms papillary carcinoma with extrathyroidal extension and 3 out of 8 lymph nodes positive. Post-operatively, she is started on levothyroxine 100 micrograms once daily. What is the target TSH level for this patient in the first year following surgery?

A. 0.5-2.0 mU/L (within reference range)
B. 2.0-5.0 mU/L (upper reference range)
C. <0.1 mU/L (suppressed below reference range) (Correct Answer)
D. 5.0-10.0 mU/L (above reference range)
E. Undetectable (<0.01 mU/L)

Explanation: ***<0.1 mU/L (suppressed below reference range)*** - This patient is classified as **high-risk** due to a large primary tumor (> 4cm), **extrathyroidal extension**, and **positive lymph nodes**. - Target **TSH suppression** to <0.1 mU/L is indicated in high-risk patients to minimize the risk of recurrence and inhibit the growth of potential residual microscopic disease. *0.5-2.0 mU/L (within reference range)* - This target is typically reserved for **low-risk** patients who have a maintained excellent response to treatment and are in **remission**. - It is inappropriate for this patient's initial post-operative phase given the aggressive histopathological features markers. *2.0-5.0 mU/L (upper reference range)* - Maintaining TSH in the upper normal range is generally avoided in thyroid cancer patients as it provides insufficient **TSH suppression**. - Higher TSH levels may theoretically stimulate the growth of remaining **follicular-cell-derived** cancer cells via TSH receptors. *5.0-10.0 mU/L (above reference range)* - These levels indicate **hypothyroidism**, which is contraindicated following surgery for differentiated thyroid carcinoma. - Elevated TSH levels increase the risk of disease progression and stimulate **thyroglobulin** production from residual tissue. *Undetectable (<0.01 mU/L)* - While profound suppression is the goal, an **undetectable TSH** is not routinely required and poses significant risks of **atrial fibrillation** and **osteoporosis**. - Guidelines generally recommend suppression to <0.1 mU/L rather than aiming for an absolutely undetectable level to balance oncological benefit and metabolic side effects.

Question 49: A 65-year-old man with type 2 diabetes for 12 years on metformin and empagliflozin presents for annual review. His eGFR has declined from 54 mL/min/1.73m² one year ago to 28 mL/min/1.73m² currently. Urine albumin:creatinine ratio is 42 mg/mmol. Blood pressure is 142/88 mmHg. He is taking ramipril 10mg once daily. HbA1c is 64 mmol/mol (8.0%). What is the most appropriate modification to his diabetes management?

A. Continue current medication and review in 3 months
B. Stop empagliflozin and continue metformin (Correct Answer)
C. Stop metformin and continue empagliflozin
D. Stop both medications and start insulin
E. Stop both medications and start gliclazide

Explanation: ***Stop empagliflozin and continue metformin*** - **Empagliflozin** (an SGLT2 inhibitor) loses significant **glucose-lowering efficacy** when the **eGFR falls below 30 mL/min/1.73m²**, necessitating its discontinuation for glycemic control, especially with an HbA1c of 8.0%. - While metformin typically requires **dose reduction** below an eGFR of 45 and is often stopped below 30, continuing it cautiously (likely with a reduced dose) while removing an ineffective agent is a reasonable initial step. *Continue current medication and review in 3 months* - The significant decline in **eGFR to 28 mL/min/1.73m²** indicates **CKD Stage 4** and warrants immediate medication review and adjustment, not just continued observation. - An **HbA1c of 8.0%** alongside worsening renal function demonstrates inadequate glycemic control, which current medications are failing to address effectively. *Stop metformin and continue empagliflozin* - Although metformin's use is often limited below **eGFR 30** due to the risk of **lactic acidosis**, continuing empagliflozin for glycemic control at an eGFR of 28 mL/min/1.73m² is not advisable due to its reduced efficacy. - This approach would leave the patient with a suboptimal and likely ineffective glucose-lowering regimen, given the high HbA1c. *Stop both medications and start insulin* - Starting **insulin** is a major escalation, and while it's safe in renal impairment, it's often considered after optimizing oral regimens or when oral agents are no longer sufficient or safe. - It is premature to stop both medications and jump directly to insulin without first adjusting existing oral therapy or considering other renal-safe oral alternatives like **DPP-4 inhibitors**. *Stop both medications and start gliclazide* - **Gliclazide**, a sulfonylurea, carries a significantly increased risk of **prolonged hypoglycemia** in patients with **severe renal impairment** like an eGFR of 28 mL/min/1.73m² because its active metabolites are renally cleared. - This medication switch would be dangerous given the patient's renal status and would heighten the risk of severe adverse events.

Question 50: A 37-year-old woman presents with anxiety, palpitations, and heat intolerance. Examination reveals a smooth, non-tender goitre and a resting tremor. Thyroid function shows TSH <0.01 mU/L, free T4 38 pmol/L, free T3 16.4 pmol/L. TSH receptor antibodies are strongly positive. She is started on carbimazole 40mg once daily. After 6 weeks, she develops a sore throat and fever. Blood tests show: Hb 118 g/L, WCC 1.8 × 10⁹/L, neutrophils 0.4 × 10⁹/L, platelets 242 × 10⁹/L. What is the most appropriate immediate management?

A. Reduce carbimazole dose to 20mg daily
B. Stop carbimazole temporarily until infection resolves
C. Continue carbimazole and prescribe antibiotics
D. Stop carbimazole and arrange urgent haematology review (Correct Answer)
E. Stop carbimazole and start propylthiouracil

Explanation: ***Stop carbimazole and arrange urgent haematology review*** - The patient has **agranulocytosis** (neutrophils < 0.5 × 10⁹/L), a rare but life-threatening complication of **carbimazole**, which mandates immediate and **permanent cessation** of the drug. - Urgent clinical management includes hospitalization for **broad-spectrum antibiotics** and a specialist review for potential treatment with **granulocyte colony-stimulating factor (G-CSF)**. *Reduce carbimazole dose to 20mg daily* - Agranulocytosis is an **idiosyncratic reaction**, not a dose-dependent one, so lowering the dose provides no protection against sepsis. - Continuing the drug at any dose in the presence of severe **neutropenia** is unsafe and delays essential recovery of the bone marrow. *Stop carbimazole temporarily until infection resolves* - Because of the high risk of **cross-reactivity** and recurrence, carbimazole must be stopped **permanently**, not just temporarily. - Re-challenging the patient with the drug later would likely trigger another episode of severe **bone marrow suppression**. *Continue carbimazole and prescribe antibiotics* - Antibiotics alone cannot resolve the underlying **drug-induced neutropenia**, and continuing the offending agent is life-threatening. - The primary cause of the **sore throat and fever** is the lack of clinical immune response due to the medication; the trigger must be removed first. *Stop carbimazole and start propylthiouracil* - **Propylthiouracil (PTU)** also carries a significant risk of **agranulocytosis** and exhibits high cross-reactivity with carbimazole. - If a patient develops agranulocytosis on one thionamide, neither should be used; alternative treatments like **radioactive iodine** or **surgery** must be considered.

Practice by Chapter

Diabetes complications and screening

Practice Questions

Diabetic emergencies (DKA, HHS)

Practice Questions

Thyroid disorders

Practice Questions

Type 1 diabetes

Practice Questions

Type 2 diabetes

Practice Questions

Want unlimited practice?

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

Start For Free