Study identifies age-related risk factors for infectious keratitis

Infectious keratitis is more severe, has more risk factors and is harder to prevent in elderly patients than in younger patients, a retrospective study found. Elderly patients also have more complications and a worse prognosis.

"Prevention should aim at minimizing topical steroid use and controlling blepharitis, ocular surface disease and herpetic eye disease," the study authors said. "Initial antibiotic treatment should include sufficient coverage of gram-positive pathogens.

In order to create a set of guidelines for infectious keratitis prevention, Ivanka J. van der Meulen, MD, and colleagues assessed age-related risk factors, microbiologic profiles and prognosis severity for 156 patients with the infection who had been admitted to two Dutch tertiary centers between January 2002 and December 2004. The patients averaged 56.6 years of age, and 49.4% were 60 years of age or older.

The most common risk factors among the elderly were systemic illness (36.4%), ocular surgery (33.8%), topical steroids (26%), blepharitis (20.8%) and herpetic eye disease (28.6%), the authors noted.

However, among younger patients, the most common risk factor was contact lens wear (62.7%; P = .000).

Gram-negative infections were more prevalent in the younger patients (52.3%; P = .000), according to the study.

"Gram-positive infections prevailed among the elderly," the authors said.

The researchers found that untreated patients had higher culture positive rates (68.7%) than patients treated with antibiotics before culturing (41.3%; P = .001).

Elderly patients had a higher risk of perforations (27.6%) than younger patients (9.9%) and had a worse average visual acuity (6/30) than younger patients (6/10; P < .005 for both).

In addition, elderly patients needed surgery more often (57.1%) than younger patients (23.4%; P < .005), according to the study, published in the June issue of Cornea.