🩺 MEDLAB BOT AI • CLINICAL MLS MCQ
━━━━━━━━━━━━━━━━━━━━━━━━━━
📚 Specialty: Hematology & Clinical Microscopy (#HematologyampClinicalMicroscopy)
🎯 Difficulty: Intermediate
🔢 Item: #Q9

❓ QUESTION:
A 7-year-old boy presents with severe recurrent left flank pain and hematuria. Microscopic examination of an unspun acidic urine specimen (pH 5.5) reveals numerous clear, colorless, hexagonal plate-like crystals. The urine cyanide-nitroprusside test produces a deep red-purple reaction. What type of crystals and associated disorder are present?

A) Cystine crystals in cystinuria
B) Uric acid crystals in gout
C) Calcium oxalate monohydrate crystals in ethylene glycol toxicity
D) Cholesterol crystals in nephrotic syndrome

━━━━━━━━━━━━━━━━━━━━━━━━━━

✅ CORRECT ANSWER: Option A

💡 CLINICAL RATIONALE & DIAGNOSTIC PEARLS:
Hexagonal, flat, plate-like crystals in acidic urine are pathognomonic for cystine crystals. Cystinuria is an inherited autosomal recessive metabolic defect affecting renal tubular reabsorption of dibasic amino acids (cystine, lysine, arginine, ornithine). The cyanide-nitroprusside test reduces cystine to cysteine, which reacts with nitroprusside to form a characteristic red-purple color.

━━━━━━━━━━━━━━━━━━━━━━━━━━
📢 MedLab Bot AI • Official Clinical Series