Which of the following clinical laboratory observations is suggestive of Hanup disease?: (A) Burnt sugar smell in urine, (B) High plasma phenylalanine levels, (C) Extremely high levels of citrulline in urine, (D) High fecal levels of tryptophan and indole derivatives
Answer is D. High fecal levels of tryptophan and indole derivatives Hanup disease is autosomal recessive metabolic disorder also known as pellagra like dermatosis. This affect the absorption of nonpolar( neutral ) amino acids specially tryptophan. So there is no absorption of tryptophan.