Results at seven years after the use of intracamerular cefazolin as an endophthalmitis prophylaxis in cataract surgery

A prospective, observational study of all patients submitted to cataract surgery over the period January 1996 to December 2009. All cases of postoperative endophthalmitis over that period were reviewed. The patients were classified in two groups: Group 1 (11,696 patients) operated on between January 1996 and December 2002, Group 2 (13,305 patients) between January 2003 and December 2009 (in whom a 1 mg/0.1 bolus of intracameral cefazolin was instilled).During the study period, 76 cases of endophthalmitis were observed in Group 1, and seven in Group 2. The rate of postoperative endophthalmitis reduced from 0.63% to 0.05% with a cefazolin injection. The relative risk (RR) for endophthalmitis in Group 1 against group 2 was 11.45 [95% CI 5.72-22.84, p < 0.001].An intracameral bolus injection of cefazolin (1 mg in 0.1 ml solution) at the conclusion of the cataract surgery significantly reduced the rate of postoperative endophthalmitis.Endophthalmitis remains a serious complication after cataract surgery, although prophylactic measures introduced in recent years have reduced the number of patients with this complication.Currently there are two streams of opinion towards endophthalmitis prophylaxis, the use of fourth-generation quinolones (gatifloxacin and moxifloxacin) topically [1-4], or the introduction of intracameral cephalosporins, the latter being cefuroxime (a second generation cephalosporin), which is the most widely used and accepted [5-10]. However, our study group [11], as well as Garat et al [12,13], prefers the use of cefazolin (a first generation cephalosporin). Having previously studied the bacteria that cause endophthalmitis in our environment most frequently, we prefer cefazolin because of its higher frequency of gram-positive bacteria in our medium, and because it best covers infections by such bacteria. Furthermore, cefazolin shows no corneal toxicity at doses of 1 mg or 2 mg; its toxicity was established when doses of 5 mg or more were injected. We con