Urinalysis and Body Fluids 6th Edition by Majorie DiLorenzo, Susan Strasinger

Exercise 15

Hartnup disease is a disorder associated with the metabolism of:

A. Organic acids

B. Tryptophan

C. Cystine

D. Phenylalanine

Step 1 of 2

Hartnup disease:

It is an inherited disorder caused by conversion of large volume of tryptophan to indole.

• The indole is reabsorbed into blood stream from intestine then circulated to liver

• In liver, indole is converted to indican, which is excreted in urine

• Diagnosis is made when mother reports blue stain in her infant’s diaper, which is called as blue diaper syndrome

Therefore, “tryptophan” metabolism is associated with Hartnup disease. Hence, the correct answer is option.