Sterile endophthalmitis following intravitreal injection of triamcinolone acetonide

To investigate clinical findings and ocular characteristics of sterile endophthalmitis following intravitreal injection (IVI) of triamcinolone for the treatment of macular edema.

IVI is an institutional practice at our hospital. From March 2002 to January 2003, a total of 21 IVIs of triamcinolone acetonide were performed on 19 patients with macular edema secondary to various retinal disorders. Cases diagnosed as sterile endophthalmitis after IVI of triamcinolone were selected for the study. Fisher's discriminant linear analysis was used to determine whether a significant correlation existed between specific ocular features and the occurrence of post-injection sterile endophthalmitis.

Five of 21 eyes (23.8%) had sterile endophthalmitis with hypopyon formation after the injection. Of the five sterile endophthalmitis patients, three were pseudophakic with impaired posterior capsule and four had a diagnosis of Irvine-Gass syndrome. The rate of sterile endophthalmitis was significantly higher in pseudophakic patients with impaired posterior capsule (p = 0.0075) and in patients with Irvine-Gass syndrome (p = 0.0008). The best-corrected visual acuity (BCVA) in these patients remained unchanged or even improved when the inflammation subsided.

Pseudophakia with impaired posterior capsule and the diagnosis of cystoid macular edema due to Irvine-Gass syndrome are two risk factors of sterile endophthalmitis following IVI triamcinolone. No loss of BCVA was noted in the patients with post-injection sterile endophthalmitis.