Treatment of Ocular Tuberculosis

Initial Phase (First 2 Months)

The American Thoracic Society recommends a standard 4-drug anti-tuberculosis regimen consisting of isoniazid, rifampin, pyrazinamide, and ethambutol for 2 months, followed by isoniazid and rifampin for an additional 4 months, for a total duration of 6 months 1, 2, 3
The initial phase must include all four first-line drugs, with isoniazid (5 mg/kg, up to 300 mg daily), rifampin (10 mg/kg, up to 600 mg daily), pyrazinamide (35 mg/kg, up to 2 g daily), and ethambutol (15 mg/kg daily) 1, 4
The fourth drug (ethambutol) can only be omitted if drug susceptibility testing confirms full susceptibility to isoniazid and rifampin, or in previously untreated patients from areas with documented low isoniazid resistance (<4% primary resistance) 2

The American Thoracic Society recommends continuing with isoniazid and rifampin daily for 4 additional months after completing the initial 2-month phase 1, 2

The treatment duration should be extended to 9 months if pyrazinamide cannot be tolerated or was not included in the initial phase, with ethambutol given for the initial 2 months with isoniazid and rifampin, then continuing isoniazid and rifampin for 7 additional months 1, 5
The treatment duration should be extended to 12 months if the patient has cerebral tuberculoma, using the same 4-drug initial phase for 2 months, then rifampin and isoniazid for 10 additional months 4, 5

The use of oral corticosteroids as adjunctive therapy may be considered, with a reasonable approach being prednisolone 60 mg daily initially, with gradual tapering over several weeks 5, 4
Corticosteroids have demonstrated clear benefit in tuberculous pericarditis and CNS tuberculosis, and may be beneficial in ocular TB 1, 5

For isoniazid-resistant TB, a later-generation fluoroquinolone (such as moxifloxacin or levofloxacin) should be added to a 6-month regimen of rifampin, ethambutol, and pyrazinamide 6, 5
For rifampin-resistant TB, a 9-month regimen of isoniazid, streptomycin, pyrazinamide, and ethambutol for 2 months, followed by isoniazid, streptomycin, and pyrazinamide for 7 months should be used 7
For multidrug-resistant TB, consultation with a TB expert is mandatory, and treatment must include at least 5 effective drugs, typically including a later-generation fluoroquinolone and an injectable agent (preferably amikacin or streptomycin, not kanamycin) 6, 7

Clinical and ophthalmologic monitoring should occur at the end of the initial 2-month phase, at the end of treatment (6-9 months), and visual acuity should be monitored throughout due to ethambutol's potential ocular toxicity 1, 4