Nitro disorders

Question 1

Cystinuria

Answer 1

• Inherited def. of Cys transporter (COAL transporter); kidney reabsorption of Cys, Ornithine, Arg, Lys (dibasic AA) decreased
• Recurrent Nephroliathiasis; morning urine sample (acidic) to see Cys crystals

Question 2

Hartnup’s Disease

Answer 2

• Inherited defect in Neutral AA (Trp) transport * decreased dietary absorption & increased excretion of Trp
• leads to NAD+ deficiency (Pellagra) since NAD+ cannot be synthesized from Trp in these Pt Sx:
• Dementia * Diarrhea * Dermatitis * Death
• Rx: diet rich in protein & niacin; avoidance of sun