Case ReportOcular Ethambutol Toxicity
Section snippets
Report of A Case
A 43-year-old man with a medical history remarkable for end-stage renal disease secondary to hypertension was hospitalized in May 2002 with shortness of breath. Chest radiography showed left-sided pleural effusion, and pleurocentesis revealed an exudative process. Pleural biopsy specimens showed extensive necrotic tissue with focal fibrosis, rare noncaseating granulomas, and acid-fast bacilli. Culture was positive for Mycobacterium tuberculosis. Isoniazid was initiated at a dosage of 300 mg
Discussion
Ethambutol toxicity is dose related. In 1 report of 18 patients treated with ethambutol at 60 to 100 mg/kg per day, 8 developed toxic optic neuropathy.2 Patients receiving 25 mg/kg per day have a 5% to 6% reported incidence of optic neuropathy, and the incidence of optic neuropathy with dosages of 15 mg/kg per day is reportedly less than 1%.8, 12 Of note, most of these reports are from tertiary referral centers and may have a detection bias because severe cases tend to be referred. Therefore,
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Ethambutol-induced toxic optic neuropathy during treatment of tuberculosis meningitis in a child
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