Abstract Introduction The use of antibiotics is very high in the departments of Emergency and Trauma Surgery above all in the treatment of the intra-abdominal infections, to decrease morbidity and mortality rates; often the antimicrobial drugs are prescribed without a rationale and they are second-line antibiotics; this clinical practice increases costs without decreasing mortality. Aim of our study is to report the results in the application to the clinical practice of the World Society Emergency Surgeons (WSES) guidelines for the management of intra-abdominal infections, at the department of Emergency and Trauma Surgery of the University Hospital of Parma (Italy) in 2012. Methods A retrospective observational analysis was carried out about patients admitted in the department of Emergency and Trauma Surgery of Parma (Italy), between January 2011 and December 2012. The data are expressed as percentages (%) and means (± SD). The results of the compared groups were analyzed using the Pearson’s Chi-Square and Fisher’s tests. For means involving continuous numerical data, the independent sample T test and the Mann–Whitney U-test were used for normally and abnormally distributed data, respectively (the data had been previously tested for normality using the Kolmogorov-Smirnov test). A p -value