1094. Safety of Administering Cefazolin vs. Other Antibiotics in Penicillin Allergic Patients with Anaphylaxis for Surgical Prophylaxis

BACKGROUND: Approximately 10% of patients report a history of penicillin allergy. Recent literature suggests cross-reactivity between cephalosporins and penicillins are due to side-chain similarities. Since cefazolin has a unique side-chain from other β lactams, it can be safely administered in penicillin-allergic patients for surgical prophylaxis. Since October 2018, our hospital updated all surgical prophylaxis preprinted orders to use cefazolin in penicillin-allergic patients, except in those with histories of cefazolin-specific allergy or delayed skin reactions (e.g., Stevens–Johnson syndrome). This study aims to retrospectively determine outcomes and safety of cefazolin as compared with other antibiotics for surgical prophylaxis in penicillin-allergic patients with histories of anaphylaxis prior to implementation of cefazolin preprinted orders. METHODS: All patients with reported anaphylactic reactions to penicillins prescribed surgical prophylaxis from October 9, 2017 to October 9, 2018 were included. Patients were stratified based on antibiotic received (i.e., cefazolin, clindamycin, vancomycin, other antibiotic) and a retrospective chart review was performed to assess for outcomes and safety. RESULTS: One-thousand-seventy-three prescriptions for prophylactic antibiotics were identified. Of these, 223 cases met inclusion with histories of anaphylaxis to pencillins: 72 (32%) cefazolin, 70 (31%) clindamycin, 34 (15%) vancomycin, and 47 (21%) other antibiotics. General and orthotrauma surgeries used the most cefazolin in penicillin-allergic patients, while gynecology clindamycin and thoracics vancomycin. Amongst those receiving cefazolin, no critical incidents of allergic reactions were reported and the rates of adverse events, such as pruritus, hives and rash, did not differ between any antibiotic group. CONCLUSION: Cefazolin appears to be a safe option for surgical prophylaxis in patients with history of penicillin anaphylaxis. No differences in incidences of allergic reactions, complications or surgical delays were reported, as compared with alternate antibiotics. Further larger studies are needed to confirm our findings and determine rates of adverse events associated with the various antibiotic regimens. DISCLOSURES: All authors: No reported disclosures.