Anti-Ro52-positive antisynthetase syndrome mimicking tuberculosis in a high-burden setting: a delayed diagnosis with therapeutic success

Antisynthetase syndrome (ASS) is a rare autoimmune condition characterized by interstitial lung disease (ILD), myositis, arthritis and characteristic cutaneous features. In tuberculosis (TB)-endemic regions, its diagnosis may be delayed owing to overlapping clinical features. We report a 52-year-old woman presenting with a 6-month history of fever and progressive dyspnoea, initially treated as recurrent respiratory infection and later empirically started on antitubercular therapy (ATT). Despite multiple hospital visits and antibiotic courses, her symptoms persisted. Imaging revealed features suggestive of ILD. Further evaluation at our centre uncovered inflammatory arthritis, myalgia, Raynaud phenomenon, elevated creatine kinase (CK) and strongly positive anti-Ro52 antibodies. Antinuclear antibody indirect immunofluorescence demonstrated a cytoplasmic staining pattern. A diagnosis of antisynthetase syndrome was made. The patient responded well to immunosuppressive therapy with azathioprine and corticosteroids, with normalization of CK levels and clinical stabilization. This case highlights the diagnostic challenges of ASS in TB-endemic regions, where empirical ATT may delay appropriate diagnosis and management. Early recognition of autoimmune features in ILD is crucial to prevent morbidity.