A 30-year-old woman has confirmed Cushing syndrome: raised late-night salivary cortisol and 24-hour urinary free cortisol, and no suppression with 1 mg dexamethasone. Plasma ACTH is 85 pg/mL (raised). Pituitary MRI shows no adenoma, and CT of the chest and abdomen is normal. What is the next best step?

Bilateral inferior petrosal sinus sampling

Repeat pituitary MRI after 1 year

A 42-year-old woman from a village near Nagpur has fatigue, salt craving and darkening of her gums for 6 months. BP 96/62 mmHg, Na 128 mmol/L, K 5.6 mmol/L. An 8 am serum cortisol is borderline low. Which test should confirm the diagnosis?

Overnight dexamethasone suppression test

A 58-year-old man who has smoked bidis for 40 years has had rapidly worsening weakness and ankle swelling for 6 weeks. He has darkened skin but no striae or central obesity. BP 170/100 mmHg, K 2.4 mmol/L, bicarbonate 34 mmol/L, glucose 260 mg/dL. Chest X-ray shows a right hilar mass. What is the most likely diagnosis?

Ectopic ACTH from small cell carcinoma

Cushing disease from a pituitary adenoma

Adrenal failure from metastases

A 26-year-old woman taking carbimazole 10 mg daily for Graves disease misses her period. Ultrasound confirms a live 6-week intrauterine pregnancy. She is clinically mildly thyrotoxic, and free T4 is just above the upper limit. What change should be made to her treatment?

Continue carbimazole at the same dose

Refer for radioactive iodine therapy

Add levothyroxine to the carbimazole

A 68-year-old man with stable angina is found to have TSH 42 mIU/L (0.4-4.5) and free T4 0.4 ng/dL (0.8-1.8). He has fatigue, constipation and dry skin. Which is the most appropriate way to start levothyroxine?

25 µg daily, increased slowly every few weeks

Liothyronine (T3) instead of thyroxine

Full replacement dose of 1.6 µg/kg/day from day 1

Thyroid, adrenal and pituitary disorders

22 NEET-PG practice questions on Thyroid, adrenal and pituitary disorders, part of General Medicine. The first 22 are below; the first 5 with answers and explanations (tap Show answer after you have chosen), the rest in Learn with a free account.

Question 1 · Hard
A 30-year-old woman has confirmed Cushing syndrome: raised late-night salivary cortisol and 24-hour urinary free cortisol, and no suppression with 1 mg dexamethasone. Plasma ACTH is 85 pg/mL (raised). Pituitary MRI shows no adenoma, and CT of the chest and abdomen is normal. What is the next best step?
1. ARepeat pituitary MRI after 1 year
2. BBilateral adrenalectomy
3. CPET-CT for an ectopic tumour
4. DBilateral inferior petrosal sinus sampling
Show answerHide answer
Answer: D · Bilateral inferior petrosal sinus sampling
The raised ACTH makes this ACTH-dependent Cushing syndrome, and in a young woman a pituitary microadenoma (Cushing disease) is by far the commonest cause, even though many are too small to see on MRI. Bilateral inferior petrosal sinus sampling with CRH or desmopressin stimulation shows a central-to-peripheral ACTH gradient in pituitary disease and none in ectopic ACTH secretion. A positive gradient leads to transsphenoidal surgery.
- A: Waiting a year leaves her exposed to the harms of cortisol excess.
- B: Bilateral adrenalectomy is a last resort and needs lifelong replacement.
- C: Functional imaging for an ectopic source comes only if sampling shows no central gradient.
Question 2 · Medium
A 42-year-old woman from a village near Nagpur has fatigue, salt craving and darkening of her gums for 6 months. BP 96/62 mmHg, Na 128 mmol/L, K 5.6 mmol/L. An 8 am serum cortisol is borderline low. Which test should confirm the diagnosis?
1. ARandom serum aldosterone
2. BCT of the adrenal glands
3. CShort ACTH stimulation test
4. DOvernight dexamethasone suppression test
Show answerHide answer
Answer: C · Short ACTH stimulation test
The features suggest primary adrenal insufficiency. The short ACTH stimulation test gives synthetic ACTH and measures cortisol at 30 or 60 minutes; failure to rise above the laboratory cut-off confirms adrenal insufficiency, and a high basal ACTH makes it primary. Once confirmed, the cause is sought: autoimmune adrenalitis is commonest worldwide, and tuberculosis is still an important cause in India, often with adrenal calcification on CT.
- A: A single aldosterone value cannot confirm cortisol deficiency.
- B: Imaging looks for the cause after the biochemical diagnosis is made.
- D: Dexamethasone suppression tests for cortisol excess, not deficiency.
Question 3 · Medium
A 58-year-old man who has smoked bidis for 40 years has had rapidly worsening weakness and ankle swelling for 6 weeks. He has darkened skin but no striae or central obesity. BP 170/100 mmHg, K 2.4 mmol/L, bicarbonate 34 mmol/L, glucose 260 mg/dL. Chest X-ray shows a right hilar mass. What is the most likely diagnosis?
1. APrimary hyperaldosteronism
2. BCushing disease from a pituitary adenoma
3. CEctopic ACTH from small cell carcinoma
4. DAdrenal failure from metastases
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Answer: C · Ectopic ACTH from small cell carcinoma
Very high ACTH levels from a small cell lung carcinoma drive extreme cortisol production over weeks, too fast for the classic cushingoid habitus to develop. Cortisol at such levels saturates renal 11-beta-hydroxysteroid dehydrogenase type 2 and acts on mineralocorticoid receptors, giving severe hypokalaemic alkalosis, hypertension and oedema; ACTH excess also darkens the skin. Hypokalaemia and hyperglycaemia need urgent control while the tumour is staged.
- A: Conn syndrome does not cause hyperpigmentation or hyperglycaemia, or link to a lung mass.
- B: Pituitary Cushing disease develops slowly and rarely causes such severe hypokalaemia.
- D: Adrenal failure causes hypotension and hyperkalaemia, the opposite of this picture.
Question 4 · Easy
A 26-year-old woman taking carbimazole 10 mg daily for Graves disease misses her period. Ultrasound confirms a live 6-week intrauterine pregnancy. She is clinically mildly thyrotoxic, and free T4 is just above the upper limit. What change should be made to her treatment?
1. ASwitch to propylthiouracil
2. BContinue carbimazole at the same dose
3. CRefer for radioactive iodine therapy
4. DAdd levothyroxine to the carbimazole
Show answerHide answer
Answer: A · Switch to propylthiouracil
In the first trimester propylthiouracil is preferred because carbimazole and methimazole can cause an embryopathy (aplasia cutis, choanal and oesophageal atresia) during organogenesis. After the first trimester many clinicians switch back to carbimazole because propylthiouracil can cause severe liver injury. The aim is to keep free T4 at the upper end of normal with the lowest dose, as thionamides cross the placenta and can make the fetus hypothyroid.
- B: Carbimazole is linked to embryopathy when given during organogenesis.
- C: Radioactive iodine is contraindicated in pregnancy and destroys the fetal thyroid.
- D: Block-and-replace needs higher thionamide doses, which reach the fetus while the thyroxine does not.
Question 5 · Medium
A 68-year-old man with stable angina is found to have TSH 42 mIU/L (0.4-4.5) and free T4 0.4 ng/dL (0.8-1.8). He has fatigue, constipation and dry skin. Which is the most appropriate way to start levothyroxine?
1. A25 µg daily, increased slowly every few weeks
2. BLiothyronine (T3) instead of thyroxine
3. CFull replacement dose of 1.6 µg/kg/day from day 1
4. DIV levothyroxine loading dose
Show answerHide answer
Answer: A · 25 µg daily, increased slowly every few weeks
Overt primary hypothyroidism needs replacement, but in older people and those with ischaemic heart disease a full dose can raise myocardial oxygen demand and provoke angina, arrhythmia or infarction. Levothyroxine is therefore started low and increased in small steps, with TSH checked about 6-8 weeks after each change. Younger, healthy adults can start near the full weight-based dose.
- B: T3 acts faster and is more likely to provoke angina.
- C: A full dose from the start risks myocardial ischaemia in an elderly man with angina.
- D: IV loading is for myxoedema coma, not stable outpatients.
Question 6 · Easy
A 30-year-old man is found to have medullary carcinoma of the thyroid with a raised serum calcitonin. Before surgery, plasma metanephrines are found to be high and CT shows a 3 cm right adrenal mass. His father died of thyroid cancer at 45. Which gene is most likely mutated?
1. AMEN1
2. BVHL
3. CNF1
4. DRET
Answer and explanation in LearnFree account
Question 7 · Medium
A 38-year-old woman has gained weight over a year, with purple abdominal striae, a round face, BP 160/100 mmHg and new diabetes. Twenty-four-hour urinary free cortisol is three times the upper limit, and cortisol is not suppressed after overnight dexamethasone. Plasma ACTH is below 5 pg/mL. What is the next investigation?
1. ACT of the adrenal glands
2. BHigh-dose dexamethasone suppression test
3. CInferior petrosal sinus sampling
4. DMRI of the pituitary
Answer and explanation in LearnFree account
Question 8 · Medium
A 66-year-old man is on day 6 of ICU care for septic shock from pneumonia and is now improving. Thyroid tests sent by the team show: TSH 0.9 mIU/L (0.4-4.5), free T4 0.9 ng/dL (0.8-1.8), total T3 45 ng/dL (80-200), reverse T3 raised. He had no thyroid disease before. What is the most likely explanation?
1. ACentral hypothyroidism
2. BPrimary hypothyroidism
3. CNon-thyroidal illness syndrome
4. DHypothyroidism from iodinated contrast
Answer and explanation in LearnFree account
Question 9 · Easy
A 28-year-old woman from Lucknow has weight loss, heat intolerance and tremor for 3 months. She has a diffuse, non-tender goitre with a bruit, bilateral proptosis and raised, thickened plaques on both shins. TSH is undetectable and free T4 is high. Which antibody is responsible for her thyrotoxicosis?
1. AAnti-thyroid peroxidase (microsomal) antibody
2. BTSH receptor-blocking antibody
3. CAnti-thyroglobulin antibody
4. DTSH receptor-stimulating antibody
Answer and explanation in LearnFree account
Question 10 · Hard
A 26-year-old staff nurse has palpitations and weight loss for 2 months. Pulse 112/min, no goitre, no eye signs, no thyroid tenderness. TSH below 0.01 mIU/L, free T4 3.8 ng/dL (0.8-1.8), ESR 12 mm/h, and 24-hour radioiodine uptake is 2%. She denies taking any tablets. Which test best separates surreptitious thyroxine intake from painless thyroiditis?
1. AAnti-TPO antibody
2. BTSH receptor antibody
3. CSerum thyroglobulin
4. DThyroid colour Doppler
Answer and explanation in LearnFree account
Question 11 · Medium
A 70-year-old woman started sertraline for depression 3 weeks ago. She now has mild nausea but is alert. She is clinically euvolaemic. Serum Na 124 mmol/L, serum osmolality 258 mOsm/kg, urine osmolality 470 mOsm/kg, urine Na 46 mmol/L; TSH and morning cortisol are normal. Four statements are made: 1. Isotonic saline will reliably correct her sodium. 2. Her urine is inappropriately concentrated. 3. Her serum uric acid is likely to be low. 4. Her sodium should rise by no more than about 10 mmol/L in the first 24 hours. Which statements are correct?
1. A2, 3 and 4 only
2. B1, 2 and 3 only
3. C2 and 4 only
4. D1, 2, 3 and 4
Answer and explanation in LearnFree account
Question 12 · Easy
A 35-year-old man with known Addison disease stopped his hydrocortisone tablets a week ago. He is brought to casualty with vomiting, abdominal pain and drowsiness. BP 78/48 mmHg, pulse 122/min, Na 124 mmol/L, K 5.9 mmol/L, glucose 64 mg/dL. Which drug should be given first?
1. AOral fludrocortisone
2. BIV noradrenaline
3. CIV 3% saline
4. DIV hydrocortisone
Answer and explanation in LearnFree account
Question 13 · Medium
A 38-year-old man has fatigue, weight loss and dizziness on standing for 4 months. BP 92/60 mmHg lying, lower on standing. The following findings are listed: 1. Hyponatraemia. 2. Hyperpigmentation of the palmar creases and buccal mucosa. 3. Fasting hypoglycaemia. 4. Hyperkalaemia. Which findings point to primary adrenal failure rather than ACTH deficiency?
1. A2 and 4 only
2. B2, 3 and 4 only
3. C1, 2 and 4 only
4. D1 and 4 only
Answer and explanation in LearnFree account
Question 14 · Hard
A 32-year-old woman with Graves disease who stopped carbimazole 3 months ago is admitted after an emergency appendicectomy. She has a temperature of 40.1°C, atrial fibrillation at 168/min, agitation and vomiting. Propranolol, propylthiouracil, hydrocortisone and potassium iodide are ordered. When should the iodide be given?
1. AOnly after radioactive iodine ablation has been given
2. BBefore the first dose of propylthiouracil
3. COne hour after the first dose of propylthiouracil
4. DOnly once the heart rate is below 100/min
Answer and explanation in LearnFree account
Question 15 · Medium
Two weeks after a viral upper respiratory infection, a 34-year-old woman has fever, palpitations and a painful front of the neck that radiates to the jaw. The thyroid is firm and very tender. ESR 82 mm/h, TSH below 0.01 mIU/L, free T4 raised, and 24-hour radioiodine uptake is 1%. What is the most appropriate treatment?
1. ATotal thyroidectomy
2. BRadioactive iodine ablation
3. CPropranolol with an NSAID
4. DCarbimazole
Answer and explanation in LearnFree account
Question 16 · Medium
A 34-year-old man from Chennai is referred with central obesity, new diabetes, hypertension, thin skin that bruises easily and difficulty climbing stairs. He takes no steroid in any form, including creams or inhalers. Which is the most appropriate first test for Cushing syndrome?
1. ARandom morning serum cortisol
2. BPlasma ACTH level
3. CMRI of the pituitary
4. DOvernight 1 mg dexamethasone suppression test
Answer and explanation in LearnFree account
Question 17 · Medium
A 35-year-old man is seen in the endocrine OPD with episodes of headache, sweating and palpitations for 6 months. During an episode his BP was 210/118 mmHg; between episodes it is 128/84 mmHg. He takes no drugs. Which test should be done first?
1. APlasma free metanephrines
2. BMIBG scintigraphy
3. CCT of the adrenal glands
4. DClonidine suppression test
Answer and explanation in LearnFree account
Question 18 · Hard
A 74-year-old woman, who had a thyroidectomy years ago and stopped levothyroxine, is brought in drowsy on a cold January morning in Shimla. Temperature 33°C, pulse 46/min, BP 90/60 mmHg, Na 122 mmol/L, glucose 62 mg/dL, PaCO2 58 mmHg. TSH is 78 mIU/L. After airway support, what is the next step?
1. AIV 3% saline to correct sodium
2. BOral levothyroxine 25 µg daily
3. CIV hydrocortisone, then IV levothyroxine
4. DActive external rewarming with heating blankets
Answer and explanation in LearnFree account
Question 19 · Medium
A 29-year-old woman delivered 8 months ago at a district hospital, where she had a massive postpartum haemorrhage and needed six units of blood. She could not breastfeed, her periods have not returned, and she now has fatigue, cold intolerance and loss of axillary and pubic hair. Serum Na 129 mmol/L. What is the most likely diagnosis?
1. ASheehan syndrome
2. BPrimary ovarian insufficiency
3. CProlactinoma
4. DAsherman syndrome
Answer and explanation in LearnFree account
Question 20 · Medium
A 45-year-old man had transsphenoidal removal of a large non-functioning pituitary adenoma 6 weeks ago. He is tired and cold. Free T4 0.5 ng/dL (0.8-1.8), TSH 1.2 mIU/L (0.4-4.5). The resident plans to start levothyroxine. What must be assessed before the first dose?
1. ASerum IGF-1
2. BAdrenal (cortisol) reserve
3. CSerum prolactin
4. DThyroid ultrasound
Answer and explanation in LearnFree account
Question 21 · Medium
A 40-year-old schoolteacher in Pune had thyroid tests at a health check. She feels well, is not pregnant and does not plan pregnancy. TSH 7.8 mIU/L (0.4-4.5), free T4 1.1 ng/dL (0.8-1.8), anti-TPO antibody positive. What is the next best step?
1. AStart levothyroxine 100 µg daily
2. BRepeat TSH and free T4 in 2-3 months
3. CUltrasound-guided FNAC of the thyroid
4. DRadioactive iodine uptake scan
Answer and explanation in LearnFree account
Question 22 · Medium
A 44-year-old man notices that his rings and shoes no longer fit. He has coarse facial features, a large tongue, sweaty doughy hands, snoring and newly diagnosed diabetes. Visual fields are normal. What is the best initial biochemical test?
1. AMRI of the pituitary
2. BRandom serum growth hormone
3. CSerum IGF-1
4. DSerum prolactin
Answer and explanation in LearnFree account

Thyroid, adrenal and pituitary disorders

A 42-year-old woman from a village near Nagpur has fatigue, salt craving and darkening of her gums for 6 months. BP 96/62 mmHg, Na 128 mmol/L, K 5.6 mmol/L. An 8 am serum cortisol is borderline low. Which test should confirm the diagnosis?

A 26-year-old woman taking carbimazole 10 mg daily for Graves disease misses her period. Ultrasound confirms a live 6-week intrauterine pregnancy. She is clinically mildly thyrotoxic, and free T4 is just above the upper limit. What change should be made to her treatment?

A 68-year-old man with stable angina is found to have TSH 42 mIU/L (0.4-4.5) and free T4 0.4 ng/dL (0.8-1.8). He has fatigue, constipation and dry skin. Which is the most appropriate way to start levothyroxine?

A 30-year-old man is found to have medullary carcinoma of the thyroid with a raised serum calcitonin. Before surgery, plasma metanephrines are found to be high and CT shows a 3 cm right adrenal mass. His father died of thyroid cancer at 45. Which gene is most likely mutated?

A 35-year-old man with known Addison disease stopped his hydrocortisone tablets a week ago. He is brought to casualty with vomiting, abdominal pain and drowsiness. BP 78/48 mmHg, pulse 122/min, Na 124 mmol/L, K 5.9 mmol/L, glucose 64 mg/dL. Which drug should be given first?

A 34-year-old man from Chennai is referred with central obesity, new diabetes, hypertension, thin skin that bruises easily and difficulty climbing stairs. He takes no steroid in any form, including creams or inhalers. Which is the most appropriate first test for Cushing syndrome?

A 35-year-old man is seen in the endocrine OPD with episodes of headache, sweating and palpitations for 6 months. During an episode his BP was 210/118 mmHg; between episodes it is 128/84 mmHg. He takes no drugs. Which test should be done first?

A 74-year-old woman, who had a thyroidectomy years ago and stopped levothyroxine, is brought in drowsy on a cold January morning in Shimla. Temperature 33°C, pulse 46/min, BP 90/60 mmHg, Na 122 mmol/L, glucose 62 mg/dL, PaCO2 58 mmHg. TSH is 78 mIU/L. After airway support, what is the next step?

A 45-year-old man had transsphenoidal removal of a large non-functioning pituitary adenoma 6 weeks ago. He is tired and cold. Free T4 0.5 ng/dL (0.8-1.8), TSH 1.2 mIU/L (0.4-4.5). The resident plans to start levothyroxine. What must be assessed before the first dose?

A 40-year-old schoolteacher in Pune had thyroid tests at a health check. She feels well, is not pregnant and does not plan pregnancy. TSH 7.8 mIU/L (0.4-4.5), free T4 1.1 ng/dL (0.8-1.8), anti-TPO antibody positive. What is the next best step?

A 44-year-old man notices that his rings and shoes no longer fit. He has coarse facial features, a large tongue, sweaty doughy hands, snoring and newly diagnosed diabetes. Visual fields are normal. What is the best initial biochemical test?