Unilateral Iris Mass Lesions in Presumed Ocular Tuberculosis

Abstract Iris mass lesions are uncommon and often raise suspicion of intraocular malignancy. However, infectious and inflammatory conditions, particularly ocular tuberculosis (TB), can closely mimic neoplastic lesions and pose significant diagnostic challenges, especially in the absence of systemic disease. A 36-year-old male presented with unilateral redness, pain, and reduced vision in the right eye for 15 days. Ocular examination revealed granulomatous anterior uveitis with two lobulated iris mass lesions and 360° posterior synechiae. Ultrasound biomicroscopy and anterior segment optical coherence tomography demonstrated well-defined lesions confined to the anterior surface of the iris, favoring an inflammatory etiology. Systemic evaluation showed no evidence of pulmonary TB; however, the interferon-gamma release assay (QuantiFERON-TB Gold) was positive, while other infectious and inflammatory investigations were negative. Based on clinicoradiological correlation and immunological evidence, a diagnosis of presumed isolated ocular TB was made. This case highlights the importance of considering ocular TB in the differential diagnosis of atypical iris mass lesions, even in the absence of pulmonary involvement. Multimodal anterior segment imaging and immunological testing are valuable tools in establishing a presumptive diagnosis and guiding timely management to achieve favorable visual outcomes.