Corneal opacities associated with NTBC treatment

PURPOSE: To describe a patient with hereditary tyrosinemia type I (HHT-I) treated with 2 (2-nitro-4-trifluoromethllbenzoyl),1,3-cyclohexanedione (NTBC) who developed corneal opacities. METHODS: A 14-month old patient was diagnosed with HHT-I and began treatment with NTBC. Her serial ocular examinations were normal until age 4 years, when she developed ocular discomfort and was found to have bilateral, linear, branching subepithelial corneal opacities. RESULTS: Over the next 3 years, the extent of the opacities fluctuated, and increased opacities correlated with periods of poor compliance with a restricted protein diet. Serum tyrosine levels remained elevated at 238 to 602 umol/L (normal 26 to 83) throughout the duration of NTBC treatment. CONCLUSION: Corneal opacities are a potential consequence of NTBC treatment for HHT-I. The lesions probably result from elevated serum and ocular tyrosine levels due to inhibition of the tyrosine catabolic pathway and poor dietary compliance. (C) 2002 by Elsevier Science Inc. All rights reserved.