[Tuberculous granuloma of the iris: a case report]

A 29-year-old man presented to Department of Ophthalmology, Affiliated Hospital of Nantong University with a 14-day history of redness and decreased vision in the right eye. Uncorrected visual acuity in the right eye was 0.02 (not improvable with correction). Slit-lamp examination revealed mutton-fat keratic precipitates on the corneal endothelium, anterior chamber inflammation, and two iris masses. Systemic evaluation suggested cervical lymph node tuberculosis, and empirical anti-tuberculosis therapy was initiated. After one month of treatment, the original iris lesion regressed, but new nodules developed. A diagnosis of iris tuberculous granuloma was suspected, and surgical excision of the iris lesions was performed. Histopathological examination demonstrated granulomatous nodules with chronic inflammatory cell infiltration. Furthermore, polymerase chain reaction analysis of vitreous fluid was positive for Mycobacterium tuberculosis DNA, confirming the diagnosis of iris tuberculous granuloma. Following continued systemic anti-tuberculosis therapy, the best-corrected visual acuity improved from 0.02 to 0.8, and the intraocular inflammation was completely controlled.