Impact of Severity of Allergy to Beta-lactam Antibiotics on the Perioperative Use of Cephalosporins and Revision Rates following Total Shoulder Arthroplasty.

Abstract

Prosthetic joint infection (PJI) after total shoulder arthroplasty (TSA) is a devastating complication. Cephalosporins are considered the standard of care for antibiotic prophylaxis during TSA procedures; however reported β-lactam allergies may result in the use of less effective alternatives which are associated with higher infection and complication rates. The aim of this study is to evaluate the relationship between reported β-lactam allergies, antibiotic choice, and revision rates in TSA. A retrospective chart review was conducted on all TSA procedures performed at a single institution between January 2015 and January 2025. Information was collected regarding reported allergies to antibiotics including allergy severity and specific reactions. Additionally, all antibiotics administered during the procedures, intraoperative reactions to administered antibiotics, surgical complications, and subsequent revision procedures were collected. Revision procedures were categorized as septic or aseptic based on preoperative diagnosis. Perioperative antibiotics and patient allergies were categorized into penicillins, cephalosporins, clindamycin, vancomycin and other. Data from 4,232 TSAs were collected. 23% of patients had a reported antibiotic allergy and 15% had a β-lactam allergy. Cephalosporins were administered in 94% of all TSAs, but use declined with increasing β-lactam allergy severity, dropping from 90% in mild cases to 44% in severe cases, with corresponding increases in clindamycin and vancomycin use. Higher allergy severity was strongly associated with reduced cephalosporin use and increased alternative antibiotic use (OR = 0.40, p<.001). Notably, cephalosporins were given to patients labeled as having anaphylactic reactions to penicillins or cephalosporins with no adverse events reported. Overall, intraoperative cephalosporin prophylaxis was significantly associated with decreased all-cause revision odds (OR = 0.47, p<.001) and the presence of a β-lactam allergy was associated with increased likelihood requiring a revision procedure for a presumed septic etiology. The severity of reported β-lactam allergies strongly influences perioperative antibiotic selection despite evidence that most reported allergies are unreliable, unnecessarily increasing patient risk for PJI. Lack of cephalosporin prophylaxis was associated with increased revision rates, underscoring the clinical and economic value of appropriate antibiotic use. Given the high prevalence of mislabeled β-lactam allergies, established delabeling strategies using allergy testing or test-dosing in the operating room may offer a safe and effective means to increase first-line antibiotic use and improve stewardship. Level III, Retrospective Cohort Comparison, Prognosis Study.