Bilateral endogenous endophthalmitis developed in a 68-year-old woman with diabetic ketoacidosis and Escherichia coli septicemia secondary to a urinary tract infection. She was started on large doses of ampicillin, and later, during her hospitalization, she received steroids. When the vitreous cleared, the fundus revealed extensive bilateral occlusion of retinal arterioles that showed the appearance of white threads. The electroretinogram was nonrecordable in both eyes except for a very small a-wave in the left eye when tested with a strong photic stimulus. The septicemia was controlled, but vision did not recover in either eye.