but in other case of 13 year-old boy without clinical signs of histidinemia , elder brother of former case , serum histidine level was 4.7 mg/dl , histidase activity was 11 % of normal control , excretion of figlu and urocanic acid in urine , and urocanic acid in sweat were observed , and the half life of histidine was 5 hours and 50 minutes ( normal : 2 hours and 20 minutes ) .
C3540840
clinical signs
C0038984
sweat