A child with pellagra like symptoms, amino acids in urine, family history of one siblings affected and three normal. Parents are normal. What is the diagnosis?

Diagnosis is Hanup's disease. autosomal recessive (normal carrier parents with 25% of their children are affected) There is failure to reabsorb tryptophan from urine.So, tryptophan comes in urine (Aminoaciduria) . Patient has Pellagra like symptoms (as Tryptophan forms Niacin - Vitamin B3 in body). Fig:-NORMAL AND ABNORMAL ROUTES OF TRYPTOPHAN Treatment: 1. Niacin 2. High protein diet