Presumed ocular tuberculosis presenting as a subfoveal choroidal granuloma in a healthcare professional: a case report

Background: Ocular tuberculosis (OTB) is a great masquerader and may occur without pulmonary symptoms, making its diagnosis challenging. In endemic regions like Malaysia, clinicians should consider OTB in patients with unexplained posterior segment ocular lesions. This report describes presumptive OTB with underlying tuberculous lymphadenitis in a healthcare professional; however, the source of tuberculosis (TB) exposure could not be established.

Case Description: A 36-year-old primary care physician with 12 years of clinical experience presented with a 1-day history of sudden wavy line vision (metamorphopsia) and a central scotoma in her left eye. Slit-lamp examination revealed a solitary yellowish choroidal granuloma with a baseline best-corrected visual acuity (BCVA) of 6/9. Although she was systemically asymptomatic, a further investigation workup led to a diagnosis of presumptive OTB with underlying tuberculous lymphadenitis. This was supported by a positive Mantoux test (14 mm), a positive interferon-gamma release assay (IGRA), and bilateral hilar lymphadenopathy on a contrast-enhanced computed tomography (CECT) thorax. Following the initiation of a nine-month course of anti-tuberculosis therapy (ATT), the patient’s vision fully restored to 6/6 alongside complete resolution of the choroidal lesion, and she remained entirely recurrence-free at the 1-year follow-up.

Conclusions: This case underscores the eye’s role as a potential clinical indicator for occult systemic TB. In endemic regions, unexplained posterior-segment ocular findings should prompt consideration of extra-pulmonary TB workup, even in the absence of pulmonary symptoms. Diagnosing OTB remains a complex clinical challenge as it is predominantly a presumptive diagnosis, where definitive confirmation typically necessitates high-risk, invasive procedures that rarely yield the pathogen.