Long-term linezolid: Unnerving the nerves?

It is well documented that systemic antimicrobials can cause ocular side effects. This becomes especially relevant in multidrug therapy where more than one drug can cause similar ocular side effect. We describe a case of progressive decrease in vision associated with linezolid therapy in a 17-year-old female patient, on treatment with the second-line anti-tuberculous drugs including linezolid, for multiple drug-resistant tuberculosis presented to us with painless progressive decrease in vision in both eyes. Color vision was defective and fundus examination revealed optic disc edema in both eyes. Since the patient was not on ethambutol and gave a history of peripheral neuropathy, linezolid-induced toxic optic neuropathy was suspected and linezolid dechallenge was done. Discontinuation of linezolid treatment resulted in marked improvement in visual acuity. Our report emphasizes the need for early detection of ocular side effects and how monitoring of visual function is imperative in patients on long-term linezolid treatment.