SPEX Internal Medicine 5 — Questions and Answers
Question 1: A 50-year-old man presents with hemoptysis, hematuria, and bilateral pulmonary infiltrates. Serum creatinine is 3.2 mg/dL and ANCA testing is strongly positive for anti-PR3 (c-ANCA). What is the most likely diagnosis?
- Goodpasture syndrome
- Granulomatosis with polyangiitis (Wegener's) (Correct answer)
- Microscopic polyangiitis
- Eosinophilic granulomatosis with polyangiitis (Churg-Strauss)
Correct answer: Granulomatosis with polyangiitis (Wegener's)
Granulomatosis with polyangiitis classically presents with upper and lower respiratory tract involvement plus renal disease, with c-ANCA/anti-PR3 positivity.
Question 2: A 38-year-old woman presents with episodic flushing, watery diarrhea, and wheezing. Urine 5-HIAA is markedly elevated. CT scan reveals a hepatic mass. What is the underlying diagnosis?
- Zollinger-Ellison syndrome
- Carcinoid tumor with carcinoid syndrome (Correct answer)
- VIPoma
- Insulinoma
Correct answer: Carcinoid tumor with carcinoid syndrome
Carcinoid syndrome (flushing, diarrhea, wheezing) occurs when carcinoid tumors metastasize to the liver, allowing serotonin to bypass hepatic metabolism; elevated urinary 5-HIAA confirms it.
Question 3: A 66-year-old man with a 40-pack-year smoking history develops progressive weakness of the proximal limbs and thighs, with strength improving after repeated muscle testing. EMG shows facilitation. Chest imaging reveals a hilar mass. What is the most likely diagnosis?
- Myasthenia gravis
- Lambert-Eaton myasthenic syndrome (LEMS) (Correct answer)
- Polymyositis
- Amyotrophic lateral sclerosis
Correct answer: Lambert-Eaton myasthenic syndrome (LEMS)
Lambert-Eaton syndrome is a paraneoplastic disorder associated with small cell lung cancer; unlike MG, strength improves with repeated activity due to facilitated calcium channel opening.
Question 4: A 28-year-old woman at 32 weeks gestation develops blood pressure of 158/104 mmHg, proteinuria 3+, and thrombocytopenia (platelets 85,000). LFTs are elevated. What is the appropriate diagnosis and management?
- Gestational hypertension — continue pregnancy to 38 weeks
- HELLP syndrome — delivery is definitive treatment regardless of gestational age (Correct answer)
- Chronic hypertension — add oral labetalol and monitor
- Preeclampsia without severe features — hospitalize and continue pregnancy
Correct answer: HELLP syndrome — delivery is definitive treatment regardless of gestational age
HELLP syndrome (Hemolysis, Elevated Liver enzymes, Low Platelets) is a severe complication requiring prompt delivery as definitive treatment, regardless of gestational age.
Question 5: A 60-year-old man with alcoholic cirrhosis develops fever, abdominal pain, and confusion. Paracentesis shows PMN count of 350 cells/µL in ascitic fluid. What is the treatment of choice?
- Oral ciprofloxacin for 5 days
- IV cefotaxime plus IV albumin infusion (Correct answer)
- Therapeutic paracentesis only
- Oral trimethoprim-sulfamethoxazole
Correct answer: IV cefotaxime plus IV albumin infusion
Spontaneous bacterial peritonitis (SBP) is treated with IV third-generation cephalosporin (cefotaxime); IV albumin reduces risk of renal failure and improves survival.
Question 6: A 55-year-old woman with rheumatoid arthritis develops sudden painless vision loss in her right eye. She has been on hydroxychloroquine for 10 years. Ophthalmology exam reveals macular 'bull's eye' changes. What is the most likely cause?
- Scleritis from RA
- Hydroxychloroquine retinal toxicity (Correct answer)
- Giant cell arteritis causing AION
- Retinal detachment from steroid use
Correct answer: Hydroxychloroquine retinal toxicity
Long-term hydroxychloroquine use can cause irreversible retinopathy with a characteristic bull's eye maculopathy; annual ophthalmologic screening is recommended.
Question 7: A 45-year-old man presents with polyuria, polydipsia, and low urine osmolality (90 mOsm/kg) despite high serum osmolality (305 mOsm/kg). After water deprivation, urine osmolality remains low but rises appropriately with intranasal desmopressin. What is the diagnosis?
- Primary polydipsia
- Nephrogenic diabetes insipidus
- Central diabetes insipidus (Correct answer)
- SIADH
Correct answer: Central diabetes insipidus
In central DI, ADH is deficient; urine fails to concentrate with water deprivation but responds to exogenous desmopressin (ADH analog), distinguishing it from nephrogenic DI.
SPEX Internal Medicine 5
A 50-year-old man presents with hemoptysis, hematuria, and bilateral pulmonary infiltrates.
Serum creatinine is 3.2 mg/dL and ANCA testing is strongly positive for anti-PR3 (c-ANCA).
What is the most likely diagnosis?