The Effect of Beta-lactam Allergy Status on the Rate of Surgical Site Infections: A Retrospective Cohort Study.

OBJECTIVE

To determine if patients with reported BL allergies have increased odds of developing SSI compared to reported NBL allergic patients.

SUMMARY OF BACKGROUND DATA

SSI represent a significant risk of morbidity and mortality for patients. Cefazolin-based perioperative antibiotic prophylaxis is the guideline-recommended drug-of-choice for most procedures. Due to over-reporting of BL allergies, many patients may not receive guideline-directed cephalosporin-based prophylaxis, which may result in an increased SSI rate.

METHODS

A single-center retrospective cohort design study was performed. Data was collected on all targeted surgical procedures: cesarean section, vaginal, and abdominal hysterectomy, colon, laminectomy, and spinal fusion surgeries.

RESULTS

During the study period, 2676 procedures were analyzed with 454 (17%) and 2222 (83%) in reported BL and NBL allergic cohorts, respectively. Significantly more SSI developed in the BL cohort versus NBL cohort (3.1% vs 1.5%, odds ratio 2.015; 95% confidence interval, 1.090-3.724; P = 0.023). Through a multivariate logistic regression, receipt of a NBL antibiotic regimen was the only variable to have a significant effect on SSI rate (adjusted odds ratio, 3.815; 95% confidence interval, 1.142-12.749; P = 0.030).

CONCLUSION

Reported BL allergic patients have an increased odds of developing SSI in comparison to NBL allergic patients. The increased risk is likely related to administration of NBL antibiotic regimens in comparison to BL-based regimens. Thorough antibiotic allergy history collection can be a valuable SSI prevention tool to safely increase the proportion of patients receiving BL regimen.