Tuberculous Uveitis

Tuberculous uveitis is intraocular inflammation caused by Mycobacterium tuberculosis infection (direct infection or hypersensitivity). It is a common cause of uveitis in endemic regions, can be the only manifestation, and mimics many other uveitis types.

• Patterns: chronic granulomatous anterior uveitis, intermediate uveitis, serpiginous like choroiditis, choroidal tubercles and tuberculoma, subretinal abscess, retinal vasculitis (including occlusive vasculitis with ischaemia, Eales disease), multifocal choroiditis, optic neuropathy, panuveitis, and endophthalmitis.
• Risk groups: people from endemic areas, HIV-infected individuals, immunosuppressed patients (anti-tumour necrosis factor biologics), contacts of infectious cases.
• Active pulmonary disease is present in a minority; most have latent infection or extrapulmonary disease.

• Painless or mildly painful reduced vision, floaters, with mutton fat keratic precipitates, iris nodules, posterior synechiae, vitritis.
• Serpiginous like choroiditis: multifocal creeping choroidal lesions with a broad advancing edge.
• Choroidal tubercles: yellow white lesions 1 to 3 mm in miliary disease; tuberculoma: large elevated mass with overlying exudative detachment.
• Retinal vasculitis with peripheral periphlebitis, haemorrhages, capillary non-perfusion, neovascularisation, and vitreous haemorrhage.
• Systemic: cough, weight loss, night sweats, fever, lymphadenopathy, and history of contact.

• Ocular examination with fluorescein angiography and optical coherence tomography.
• Interferon gamma release assay or tuberculin skin test (induration over 10 mm; over 5 mm in immunosuppressed); these show infection but not active ocular disease.
• Chest X-ray and CT chest; sputum or gastric aspirate for acid fast bacilli, culture and nucleic acid amplification when pulmonary disease is suspected; biopsy of accessible tissue.
• Aqueous or vitreous polymerase chain reaction for M. tuberculosis (IS6110, MPB64), supportive but not excluding when negative.
• Exclude syphilis and sarcoidosis, test for HIV.
• Presumptive diagnosis: compatible ocular findings, evidence of tuberculosis infection (positive interferon gamma release assay, chest imaging), exclusion of other causes, and good response to antituberculous therapy.

• Antituberculous therapy (4 drug) with an infectious disease or chest physician:
  • Isoniazid 5 mg/kg daily (maximum 300 mg) with pyridoxine 25 to 50 mg daily, rifampicin 10 mg/kg daily (maximum 600 mg), pyrazinamide 25 mg/kg daily (maximum 2 g), and ethambutol 15 mg/kg daily for 2 months (intensive phase), then isoniazid and rifampicin for 4 to 7 months (total 6 to 9 months; some programmes use up to 12 months for ocular disease).
  • Ethambutol requires baseline and monthly visual acuity, colour vision and disc checks (optic neuropathy risk).
  • Monitor liver function (baseline, 2 and 4 weeks, then as needed).
• Anti-inflammatory therapy after antituberculous therapy is started (at least 1 to 2 weeks): prednisolone 1 mg/kg daily tapered over 4 to 8 weeks, or periocular steroid; topical prednisolone acetate 1 percent and atropine 1 percent for anterior disease. Steroids without anti-tuberculous cover can worsen the infection.
• Retinal ischaemia and neovascularisation: panretinal photocoagulation, and intravitreal anti-VEGF (bevacizumab 1.25 mg) for neovascular complications; vitrectomy for non-clearing haemorrhage or tractional detachment.
• Paradoxical worsening on treatment (immune reconstitution) may need increased steroid.
• Before starting biologics, treat latent tuberculosis (isoniazid 300 mg daily for 6 months, or rifampicin 600 mg daily for 4 months).
• Contact tracing and notification.