Dual Margins on Autofluorescence in Tubercular Serpiginous-Like Choroiditis: A Biomarker for Increased Risk of Paradoxical Worsening and the Need for Immunosuppression.

PURPOSE: To assess the prognostic role of dual margins on fundus autofluorescence (AF) in predicting treatment outcomes in tubercular serpiginous-like choroiditis (TB SLC).

DESIGN: Retrospective interventional study.

METHODS: Patients with active TB SLC demonstrating dual hyperautofluorescent margins with an intervening hypoautofluorescent zone on baseline AF, positive laboratory evidence of tuberculosis, radiological evidence of active or healed TB, and ≥3 months follow-up were included. Each case was matched with three controls without dual margins. All patients received oral corticosteroids (prednisolone 1 mg/kg, tapered over 1-2 months) with concurrent antitubercular therapy. Primary outcomes were paradoxical worsening (PW), recurrence, and need for additional immunosuppression. Logistic regression was used to analyze risk factors for PW.

RESULTS: Three hundred and sixty-six patients of active SLC were screened and twenty-one cases and 63 controls were evaluated. PW occurred significantly more often in the dual-margin group (47.6% vs. 14.3%, = .002). Recurrence rates were comparable (9% vs. 6%, = .63). Escalation of immunosuppression, including increased corticosteroid use or additional immunomodulatory therapy, was required more frequently in cases (47.6% vs. 20.6%, = .01).

CONCLUSION: Dual AF margins may serve as an imaging biomarker of aggressive TB SLC and may predict higher risk of PW and greater immunosuppressive requirements. Early recognition may facilitate closer follow-up and timely therapeutic escalation.