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

Hanup's disease : disease is caused by a mutation(six mutations in SLC6A19) of the gene that controls the processes of amino acid absorption and reabsorption. Symptoms: * sensitivity to light * anxiety * rapid mood swings * hallucinations * delusions * intention tremor * speech difficulties * abnormalities in muscle tone: either muscles can become more tight DIAGNOSIS: * Blood Test * Urine Test * Prenatal Screening Based On the Symptoms Treatment: * consists of a change in diet, avoidance of sunlight, and prescribing sulfonamide drugs * Consuming foods that contain the B-complex vitamin niacin can significantly reduce your symptoms. * Good sources of niacin include: meat poultry fish foified and whole grains peanut butter potatoes B-complex or niacin vitamin supplements (such as nicatonic acid) Reference: Harpers illustrated biochemistry 30th edition