Latanoprost-induced iris heterochromia and open-angle glaucoma: A clinicopathologic report

Purpose: To report the histopathologic and immunohistochemical findings fro m the iridectomy specimen of a patient with acquired unilateral iris hetero chromia due to latanoprost. Patient and Methods: A 45-year-old woman with open-angle glaucoma and unila teral iris heterochromia was evaluated for uncontrolled intraocular pressur e increase. Subsequently, the patient underwent trabeculectomy with mitomyc in C and an iridectomy specimen was obtained for analysis. Results: The histopathologic analysis of the iridectomy specimen did not re veal any nuclear atypia, nuclear crowding, or mitotic figures. Immunohistoc hemical studies showed that the iris melanocytes were negative for HMB45 an d S-100, and weakly positive for Melan A. Conclusion: Latanoprost-associated iris color change may exhibit a diffuse, uniform, dark velvet-brown appearance, thereby simulating diffuse iris mel anoma. Histopathologic and immunohistochemical analysis confirmed the benig n characteristics of the affected iris melanocytes.