Acute Endophthalmitis Following Cataract Surgery Among US Medicare Beneficiaries in 2003-2004

Abstract

Methods: : We derived our sample from the 2003-2004 national Medicare billing database, which accounts for the majority of cataract surgeries in the United States. Cataract surgeries were identified by 2003-2004 standard current procedure terminology (CPT) codes. Among these surgeries, presumed endophthalmitis cases were identified by at least one billing claim in which endophthalmitis ICD-9 codes were used for billing diagnosis within six weeks following cataract surgery. All presumed post-operative endophthalmitis cases that occurred in the states of California, Texas, Illinois, Florida and Michigan were included. Treating physicians were contacted via telephone and requested to complete a questionnaire on clinical and microbiological data.

Results: : We describe 586 cases of presumed post-operative endophthalmitis. Median time to first Medicare claim was 6 days, typically within 2 days of symptom onset. At presentation, 68% of presumed cases had hypopyon and 61% had vitritis; wound leak was present in 8%. Prior to treatment, the majority (75%) of presumed endophthalmitis cases had VA worse than 20/200. Culture results were available for 86% of presumed cases and 55% were culture-proven. Identified organisms were 94% gram positive, 5% gram negative and 1% fungi. The most predominant organisms were coagulase-negative Staphylococcus (58%), Staphylococcus aureus (16%) and Staphylococcus, species unspecified (10%).

Conclusions: : This study yields a representative picture of post-cataract surgery endophthalmitis in the United States. Organisms implicated were similar to those reported by prior US studies.

Keywords: endophthalmitis • cataract