Microbial keratitis after LASIK

Abstract

Purpose: To report cases of microbial keratitis after LASIK from a tropical climatic zone.

Methods: This retrospective case series included 17 eyes of 15 patients managed at our center from January 1999 to December 2007. All patients had a detailed clinical evaluation followed by corneal scrapings. The material obtained on scraping was subjected to detailed microbiology evaluation. Initial medical treatment was based on microbiology results and included irrigation of the interface with appropriate antimicrobial solutions. The flap was amputated in patients who developed flap necrosis. N-butyl cyanoacrylate tissue adhesive was applied for gross thinning and penetrating keratoplasty (PK) was performed for advanced cases of keratitis.

Results: Mean patient age was 25.8 years (range: 18 to 44 years). Two patients had undergone unilateral surgery. Thirteen patients presented with infection in 1 eye and 2 patients had bilateral infection. The microorganisms isolated were filamentous fungi (4 eyes), Nocardia asteroides (5 eyes), atypical mycobacteria (4 eyes), Acanthamoeba (2 eyes), Corynebacterium (1 eye), and Staphylococcus epidermidis (1 eye). The infection resolved with medical treatment in 6 eyes, medical treatment and flap amputation in 4 eyes, and PK in 4 eyes. Two patients were lost to follow-up. Five eyes of 4 patients referred to us within 10 days of symptom onset resolved on medical treatment with final visual acuity ranging from 20/20 to 20/80.

Conclusions: In a tropical region, it is important to consider uncommon organisms such as fungi, Nocardia, and Acanthamoeba as possible etiological agents in keratitis after LASIK. A detailed microbiology work-up will help in definitive diagnosis and appropriate treatment.