Outcome of Tyrosinemia Type 1 in Indian Children

Aim: The objective of this study was to determine the outcome of children with tyrosinemia type 1 from India.

Methods: A retrospective observational study was conducted on 11 patients diagnosed with type I tyrosinemia under our care. Age at symptoms, age at diagnosis, age at starting 2-nitro-4-trifluoromethylbenzoyl-1,3-cyclohexanedione (NTBC), duration between diagnosis and initiation of NTBC, dose given, total duration of NTBC, and outcomes were noted.

Results: Eleven children with a median age of 1.1 years (0.51-1.52) at onset of symptoms were included in the study. The median age at diagnosis was 1.76 years (0.95-2.43). Their current median age is 5.44 (2.36-8.80) years. Common clinical features at presentation were chronic liver disease in 8 (72.72%), rickets in 2 (18.18%), and fulminant liver disease in 1 (9.09%) patient. Hepatomegaly was observed in all children, growth retardation in 9 (81.81%), coagulopathy in 8 (72.72%), and abdominal distention in 6 (54.54%) patients. The median duration of NTBC therapy was 13.5 (7-21.25) months. The median dose of NTBC was 1 (0.77-1) mg/kg/day. One (9.09%) patient died due to liver cell failure. However, she had received NTBC only for a month. Another patient developed hepatocellular carcinoma (HCC) and underwent liver transplantation. He could receive NTBC only for 2 months, although he was diagnosed to have tyrosinemia for over a 1 year. Eight patients are on treatment with NTBC and are doing well, and 1 patient is not on NTBC and continues to have renal tubular acidosis.

Conclusion: NTBC therapy is effective and improves the prognosis of tyrosinemia. A long-term follow-up is required to determine progression to HCC and need for liver transplantation.