How long is antibiotic therapy necessary after urgent cholecystectomy for acute cholecystitis?

The objective of the study was to analyze surgical site infection (SSI) frequency with different duration antibiotic courses to establish the minimum necessary duration.

This is an observational study of prospective surveillance of 287 consecutive patients (mean age 67.8 years) operated on for acute cholecystitis of grade II severity in the first 72 h. Postoperative antibiotics had been withdrawn before diagnosis of any infection as an inclusion criterion. Patients were classified into three groups, according to therapy duration: group 1 (0-4 days, n = 45, 15.7 %); group 2 (5-7 days, n = 75, 26.1 %); and group 3 (>7 days, n = 167, 58.2 %). A multivariable analysis of risk infection was performed.

Overall SSI frequency in groups 1, 2, and 3 was 2.2, 10.7, and 9 %, respectively. Risk analysis showed an increase in both crude and adjusted relative risks of overall infection in group 2 (crude relative risk (RR): 4.80 (0.62-37.13); adjusted RR, 2.03 (0.20-20.91)) and in group 3 (crude RR, 4.04 (0.55-29.79); adjusted RR, 2.35 (0.28-20.05)) by comparison with group 1, although without statistical significance. As a result, treatment lasting 4 days or less was not associated with overall surgical site infection incidence higher than longer treatment.

Antibiotic treatment over 4 days after early cholecystectomy provides no advantage in decreasing surgical site infection incidence.