| HIAA urine levels are suggestive of

Patients with renal disease may have falsely low 5-HIAA levels in the urine. 5-HIAA is increased in untreated patients with malabsorption, who have increased urinary tryptophan metabolites. Such patients include those with celiac disease, tropical sprue, Whipple disease, stasis syndrome, and cystic fibrosis. Ref: guyton and hall textbook of medical physiology 12 edition