Leber's hereditary optic neuropathy mutations in ethambutol-induced optic neuropathy.

Primary mitochondrial DNA (mtDNA) mutation at the nt 11778 site in Leber's hereditary optic neuropathy (LHON) has been reported to be present in patients with ethambutol-induced optic neuropathy. To study further this association between LHON and ethambutol-induced optic neuropathy, we tested ethambutol-induced optic neuropathy patients for the presence of the mtDNA mutations at nucleotides (nt)-11778, nt-14484, nt-3460, nt-15257, nt-9438, nt-9804, nt-13730, and nt-14459 in 24, 15, 8, 6, 5, 5, 5, and 5 patients respectively. However, none of the ethambutol-induced optic neuropathy patients was found to exhibit any pathogenic LHON mtDNA mutation. In conclusion, we found no evidence of any association between ethambutol-induced optic neuropathy and the LHON mutations.