Serum type III procollagen in children with type I hereditary tyrosinemia

Background: Type I hereditary tyrosinemia leads to hepatic dysfunction and fibrosis and is associated with a high risk of hepatic malignancy. Serum N- terminal propeptide of type III procollagen is a sensitive marker of organ fibrosis of diverse origins. The current study was conducted to determine w hether analysis of serum levels of type III procollagen in hereditary tyros inemia would be useful in the follow-up of the progressive liver disease an d eventually in detecting hepatic malignancy. Methods: Serum N-terminal propeptide of type III procollagen was sequential ly studied in 10 children with type I hereditary tyrosinemia. Results: At diagnosis of type I hereditary tyrosinemia, serum N-terminal pr opeptide of type III procollagen ranged from 0.6 to 2.9 multiples of age-re lated median. During follow-up, serum N-terminal propeptide of type III pro collagen decreased, yet remained elevated 0.2 to 2.6 years after diagnosis. Children with the acute type of the disease tended to have higher serum N- terminal propeptide of type III procollagen than did those with the chronic type. Porphyria crises were associated with elevated serum type III procol lagen. The one patient receiving 2-(2-nitro-4-trifluoromethyl-benzoyl)-1,3- cyclohexanedione (NTBC) did not differ from the other ones in serum type II I procollagen levels. Serum N-terminal propeptide of type III procollagen d id not increase with developing hepatocellular carcinoma. Conclusions: Serum N-terminal propeptide of type III procollagen may be use ful in monitoring the hepatopathy in type I hereditary tyrosinemia but is n ot useful in detecting malignant transformation in the liver.