The incidence of sickle trait in Blacks requiring filtering surgery.

Open-angle glaucoma in the blacks is generally thought to be a more malignant disease than in whites in terms of response to therapy and subsequent visual loss. An increased incidence of unsuspected sickle trait and undetected sickling may have contributed to these patients' optic nerve ischemia, progressive field loss and need for surgery. A homoglobin electrophoresis was done on 40 black patients who required filtering surgery for uncontrolled open-angle glaucoma. Only 2 of the 40 patients (5%) had sickle trait as determined by the hemoglobin electrophoresis. In a matched group of 40 controls, only 3 patients (7.5%) had sickle trait. Therefore, there does not appear to be an increased incidence of sickle trait in black patients requireing filtering surgery.