Endophthalmitis after cataract surgery: Risk factors relating to techniqueand events of the operation and patient history - A retrospective case-control study

Objective: This study aimed to investigate the relationship between postope rative endophthalmitis and current changes in the cataract operative techni que. Design: A retrospective case-control study. Participants: The 22,091 cataract operations performed from 1990 through 19 93 at St Eriks Hospital formed the basis for this investigation. In a rando m fashion, 220 control subjects were selected to be compared with the endop hthalmitis cases. Main Outcome Measures: Numerous variables pertaining to the cataract extrac tion procedure and to the ocular and general health of patients with catara cts were analyzed regarding the development of postoperative intraocular in fection. Patient age, presence of diabetes or immunosuppression, type of ca taract extraction and intraocular lens (IOL), and intraoperative or postope rative complications were the principal variables assessed. Results: Fifty-seven patients with endophthalmitis were diagnosed, resultin g in an overall frequency of 0.26%. Immunosuppressive treatment (P = 0.019) , wound abnormality (P = 0.03), and the use of IOLs without a heparinized s urface (P = 0.0023) were the only significant risk factors found in a logis tic regression model. Conclusions: The results suggest that cataract operating practice may alter the risk for endophthalmitis in that implanting a heparinized IOL and crea ting a tight section both seem to provide protection against this dreaded c omplication. Regarding patient history, an increased susceptibility was fou nd among subjects treated with immunosuppressants. Designing a prophylactic protocol that protects against endophthalmitis more efficiently than did t he study prophylaxis of 20 mg of subconjunctival gentamicin, is important n ot only for this patient subgroup but also for the cataract operated popula tion at large.