Corneal opacities associated with NTBC treatment.
OBJECTIVE
To describe a patient with hereditary tyrosinemia type I (HHT-I) treated with 2-(2-nitro-4-trifluoromethylbenzoyl)-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.


CONCLUSIONS
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.
Department of Ophthalmology and Visual Sciences (S.A., G.T.L.), Washington University Medical Center and St. Louis Children's Hospital, St. Louis, Missouri 63110, USA
Saad
S
Ahmad
Jeffrey H
JH
Teckman
Gregg T
GT
Lueder
D015111:4-Hydroxyphenylpyruvate Dioxygenase / Q000037:antagonists & inhibitors; D002675:Child, Preschool; D003315:Cornea / Q000187:drug effects* / Q000503:physiopathology; D003318:Corneal Opacity / Q000139:chemically induced* / Q000503:physiopathology; D003512:Cyclohexanones / Q000009:adverse effects*; D018753:Diet, Protein-Restricted; D004791:Enzyme Inhibitors / Q000009:adverse effects*; D005260:Female; D006801:Humans; D009579:Nitrobenzoates / Q000009:adverse effects*; D014443:Tyrosine / Q000097:blood; D020176:Tyrosinemias / Q000097:blood / Q000188:drug therapy*
D003512:Cyclohexanones; D004791:Enzyme Inhibitors; D009579:Nitrobenzoates; D014443:Tyrosine; D015111:4-Hydroxyphenylpyruvate Dioxygenase; C077073:nitisinone