The association of penicillin allergy with outcomes after open ventral hernia repair.

Background: Up to 11% of patients report a penicillin allergy (PA), with 1-2% demonstrating a true IgE mediated allergy upon testing. PA patients often receive non-beta-lactam antibiotic surgical prophylaxis (non-BLP). This study evaluates the relationship of PA to outcomes after open ventral hernia repair (OVHR).

Methods: A prospective institutional database was queried for patients undergoing OVHR. Demographics, operative characteristics, and outcomes were evaluated by the reported PA and the administration of beta-lactam prophylaxis (BLP).

Results: Allergy histories were reviewed in 1178 patients. PA was reported in 21.6% of patients, with 55.5% reporting rash or hives, 15.0% airway compromise or anaphylaxis, and 29.5% no specific reaction. BLP was administered to 76.3% of patients, including 22.1% of PA patients and 89.9% of patients without PA. PA patients were more often female (64.6% PA patients vs. 56% non-PA, p = 0.01), with higher rates of chronic steroids, MRSA, anxiety, asthma, COPD, chronic pain, and sleep apnea (p < 0.03 all values). PA patients had higher rates of contaminated cases, including mesh infection and fistula. Of the 683 clean cases, 82.1% received BLP. Of the 117 clean contaminated cases (CDC wound class 2), 82.9% received BLP, which was associated with reduced long-term readmission for hernia complications (21.5 vs. 55%, p = 0.002, OR 0.27, CI 0.09-0.83). In the 120 CDC wound class 3 and 4 patients, 65.8% received BLP. In multivariate analysis, BLP was associated with lower rates of reoperation (OR 0.31, CI 0.12-0.76) and recurrence (OR 0.32, CI 0.11-0.86). BLP was given to 22.1% of the PA patients with no adverse reactions noted.

Conclusion: PA patients had more comorbidities and complex ventral hernias. When controlling for contamination and MRSA history, BLP is associated with improved outcomes particularly in contaminated cases. PA may be a risk factor for patient complexity, and further studies are warranted to determine if allergy testing can be warranted in known or anticipated contaminated cases.