Peripheral retinal microaneurysms in chronic leukemia.

Of 25 patients with chronic leukemia, there was clinical evidence of peripheral retinal microaneurysm formation in two of eight patients with chronic lymphocytic leukemia and six of 17 patients with chronic myelogenous leukemia. There was no proliferative retinopathy in any of the 25 patients. An elevated leukocyte count seemed necessary for microaneurysm formation in leukemia, although some patients with elevated counts had no microaneurysms. The prolonged leukocytosis of chronic leukemia can produce peripheral capillary dropout, vascular stagnation, microaneurysm formation, and, rarely, peripheral proliferative retinopathy similar to sickle cell disease.