We report a case of optic neuropathy in a patient who was treated with pre-extensively drug-resistant tuberculosis(pre-XDR TB) treatment with linezolid. Case summary

A 61-year-old male patient with no other underlying disease was diagnosed with pre-XDR Tb 6 months before and took the TB drug at another hospital. Ethambolol was not prescribed because it was resistant from the beginning of TB treatment. Threrefore, linezolid was included for treatment of pre-XDR TB. The patient's best corrected visual acuity was 20/400 in both eyes at the time of outpatient visit. In Ishihara color vision test, both eyes showed complete color blindness. There was no detectable relative afferent pupillary defect, and fundus examination showed hyperemic optic discs and visual field examination showed both central visual field defects. Linezolid induced optic neuropathy was suspected, the drug was discontinued. After one month, the patient's best corrected visual acuity recovered to 20/20 in both eyes, and visual field and color vision returned to normal at 3 months. Conclusions

Linezolid is a broad spectrum antibiotic and is a useful drug for the treatment of broad-spectrum tuberculosis. However, since long-term use may cause optic neuropathy, the possibility of optic neuropathy should always be considered. If optic neuropathy is suspected, prompt drug withdrawal is required and reversible clinical changes can be expected.