Ocular tuberculosis: A differential diagnosis-based review

Abstract

Ocular tuberculosis (OTB) remains one of the most challenging forms of extrapulmonary TB. Its clinical manifestations overlap extensively with infectious and noninfectious inflammatory, as well as neoplastic conditions. Microbiological confirmation from ocular tissues is rarely available, while commonly used tests such as the tuberculin skin test and interferon-gamma release assays have limitations in both sensitivity and specificity. Consequently, the diagnosis of OTB relies heavily on clinical judgment. In this review, we adopt a differential diagnosis-based framework to evaluate the most common OTB phenotypes, including scleritis, granulomatous anterior uveitis, intermediate uveitis, retinal vasculitis, choroidal granuloma, multifocal choroiditis, and serpiginous-like choroiditis. For each phenotype, we highlight the key clinical, imaging, and laboratory features that help distinguish OTB from its closest mimickers. We also propose a practical six-step diagnostic algorithm that integrates ocular phenotype, differential diagnoses, supportive evidence for TB, and phenotype-specific treatment thresholds to guide decisions regarding antitubercular therapy. A differential diagnosis-driven approach may reduce both overdiagnosis and underdiagnosis of OTB and facilitate more rational, phenotype-specific management in clinical practice.