INTRODUCTION: The main objective of the study was to assess the adequacy of antibiotic therapy for urinary tract infections (UTI) in a French hospital medical department. The secondary objective was to identify factors associated with inadequacy of the antibiotic therapy. METHODS: A retrospective single centre cohort study was performed in the Post-Emergency Medicine Department (PEMD) of the university hospital of Lille. All patients presenting with an UTI from May 2012 to April 2014 were included. Adequacy of antibiotic therapy was assessed with reference to local guidelines. Factors associated with inadequacy of antibiotic prescription were determined using a multivariate logistic regression model. RESULTS: Two hundred and twenty-eight patients were included. The antibiotic prescription was fully adequate in 173 patients (76%) with appropriate use of a single or a combination antibiotic therapy in 96%, appropriate drug in 80%, appropriate dosage in 89% and appropriate route of administration in 95%. The risk for antibiotic inadequacy was significantly higher in patients with cystitis than in those with pyelonephritis (OR 12.01; 95% CI 4.17-34.65), when antibiotics were prescribed in the Emergency Department (OR 6.84; 95% CI 2.29-20.47) or before hospital admission (OR 382.46; 95% CI 19.61>/=999.99) compared to when antibiotics were first administered in the PEMD, and in patients with severe UTI (OR 19.55; 95% CI 2.79-137.01). CONCLUSION: Adequacy of antibiotic therapy for UTI is relatively high in our study, reflecting the effective dissemination of antibiotic guidelines. However, antibiotic therapy is still inappropriate in cystitis, severe UTI and in case of prescription before the admission in the PEMD.