Total Shoulder Arthroplasty: Antibiotic Allergies Increase Risk of Postoperative Complications

Background: Periprosthetic infections after total shoulder arthroplasty (TSA) are associated with devastating complications and prolonged treatment. Patients with identified antibiotic allergy (ABX) may be at increased risk for complications because of suboptimal preincisional prophylaxis. This study aims to quantify the risk of postoperative outcomes and complications for patients undergoing TSA with a history of ABX. Methods: Retrospective cohort analysis of patient data was conducted using the PearlDiver Patient Records Database. Patients who underwent TSA for osteoarthritis were identified using Current Procedural Terminology and International Classification of Diseases codes and were stratified based on self-reported (1) penicillin, (2) sulfonamide, or (3) other antibiotic allergies. We analyzed patient demographics, comorbidities, 90-day medical complications, and rate of revision at 30 days, 90 days, 1 year, and 2 years. Results: In total, 85,606 patients who underwent TSA for osteoarthritis from 2010 to 2018 were identified, of whom 7,836 (9.15%) had a reported ABX. Univariate analysis found the ABX cohort was younger (67.5 versus 67.7 year; P = 0.042), more often female (67.57% versus 54.79%; P < 0.001), and more likely to have Elixhauser comorbidities than nonallergic control subjects. Multivariate analysis found patients who reported ABX had increased likelihood of periprosthetic joint infection (PJI) within 30 days (odds ratio [OR]: 3.129), 1 year (OR: 2.016), and 2 years of surgery (OR: 2.221). Patients with reported ABX had increased likelihood of postoperative anemia (OR: 1.126), blood transfusion (OR: 1.238), and readmission (OR: 1.585) within 90 days of surgery. Patients with penicillin allergy had a greater incidence of revision due to PJI at 30 days (OR: 4.811), 90 days (OR: 2.91), 1 year (OR: 2.105), and 2 years (OR: 2.72). Rates of reported ABX increased from 2010 to 2018 (8.60% to 10.91%; P = 0.001) in patients undergoing TSA. Conclusion: Patients undergoing TSA with a history of ABX had a higher risk of readmission, postoperative anemia, blood transfusions, and PJI. These findings support critical assessment and clarification of reported allergies before TSA and possibly the use of preoperative allergy testing. Level of Evidence: Level 3 therapeutic study