MedGen

Hartnup disorder (HND) is characterized by transient manifestations of pellagra, cerebellar ataxia, and psychosis. It is caused by impaired transport of neutral amino acids across epithelial cells in renal proximal tubules and intestinal mucosa (summary by Kleta et al., 2004). [from OMIM]

The presence of an abnormally increased concentration of neutral amino acids in the urine. The neutral amino acids are tryptophan, alanine, asparagine, glutamine, histidine, isoleucine, leucine, phenylalanine, serine, threonine, tyrosine and valine. [from HPO]