KnowraHartnup diseaseLinked fromLinked fromThe 3 pages that link to Hartnup disease, each with the reason it gives.All 3Related 2Compared with 1TryptophanRelated: Reduced intestinal uptake and kidney reabsorption can cause tryptophan deficiency.PellagraRelated: Reduced tryptophan availability can limit niacin production and cause pellagra-like illness.CystinuriaCompared with: It also causes amino-acid transport abnormalities but does not chiefly produce cystine stones.