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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Porphobilinogen in urine produces pink colour with-
assistant
The correct answer is  Ehrlich's aldehyde reagent test is used for porphobilinogen and urobilinogen in urine. It is mainly used in acute intermittent porphyria.

About other options

Sodium nitroprusside (Rothera's test) → For ketone bodies
Benedict's test                                     → Glucose and other reducing sugars in urine
Fouchet's (barium sulphate) test         → Bile pigment (bilirubin)