Risk of Endophthalmitis in Diabetic Patients

Endophthalmitis--infection inside the eye--is a medical emergency most likely to happen to people who recently had eye surgery or injury. Although the condition is uncommon, it can result in permanent loss of vision, especially if proper diagnosis and treatment is delayed. Diabetes increases the odds of getting endophthalmitis and also makes for a worse outcome.

Symptoms

• Symptoms of endophthalmitis are pain, sensitivity to light, partial or total loss of vision and redness of the white portion of the eye. Pus might be visible behind the lens of the eye and the eyelid can be swollen as well.

Typical cause

• In the U.S., the typical cause of endophthalmitis is bacterial infection after cataract surgery. Symptoms show up within four to six weeks after surgery in 75 percent of cases, but in some cases do not develop for months or years afterward. The later symptoms develop, the milder they tend to be.

  According to an article in the October 2008 "Retinal Physician" magazine, post-operative endophthalmitis occurs in about 1 in 1,000 cataract surgery patients. About 2 million cataract operations are performed annually in the U.S., the article reads.

Diabetes and risk

• Emergency physician Dr. Alan Adams, on staff at Heart of the Rockies Regional Medical Center, Salida, Colo., said he's seen perhaps five cases of endophthalmitis in his 20 years practicing emergency medicine.

  "The outcome depends on the virulence of the organism and the quickness of treatment," Adams said.

  In a 1994 study published by Medline found that 21 percent of 162 patients treated for endophthalmitis within two weeks of eye surgery had diabetes. They also found that diabetic patients tended to have poorer vision after treatment when compared to non-diabetics.

  A 2001 study published by the National Institutes of Health concluded that among 420 patients treated for endophthalmitis after cataract surgery, 58 had diabetes. The diabetic patients generally had slightly worse vision before surgery than non-diabetic patients, and were less likely to achieve acceptable final vision after the infection. Researchers also noted that removal of some of the vitreous fluid from inside the eye during treatment of endophthalmitis gave better final results to some diabetic patients--though there were not a sufficient number of diabetics with "better than light-only" vision in the study group to draw a firm conclusion.

  A 2006 Japanese study of four diabetic patients treated for endophthalmitis concluded that all four had poor control of their diabetes before surgery.

  "Because long-term poor glycemic control can lead to endophthalmitis, strict glycemic control is necessary to avoid ocular infections in patients with (Type 2 diabetes)," researchers wrote.

Prognosis

• According to the 2001 study, only 39 percent of diabetic patients achieved 20/40 vision after endophthalmitis--the ability to see an object 20 feet away with the same clarity as someone with perfect vision standing 40 feet away. In comparison, 55 percent of non-diabetic patients achieved 20/40 vision.

Prevention

• If you have diabetes and are considering eye surgery, get your blood glucose levels under control well before your surgery date to make it less likely you will develop endophthalmitis.

  After surgery, follow your doctor's care instructions and do not skip follow-up examinations.