BACKGROUND: The objective of this study is to identify and characterize the species resistance of different pathogens between community acquired and hospital acquired infections pointing at patients' related independent co-morbidities and socio-demographic factors. METHODS: It was a retrospective cohort, multicenter study from five private hospitals located in Beirut and Mount Lebanon. Two hundred fifty-eight adult patients were included. RESULTS: 110 Gram negative pathogens and 26 Gram positive pathogens were implicated in hospital acquired infections. The Gram-negative bacteria that showed a positive correlation regarding patient's type of infection were Pseudomonas aeruginosa (12%), Klebsiella pneumoniae (6.2%) and Acinetobacter baumannii (3.1%). These bacteria were more frequent in patients with hospital acquired infections (P=0.002, 0.013 and 0.017 respectively). The ratio of methicillin resistant Staphylococcus aureus, Extended Spectrum Beta Lactamase producing Escherichia coli and K. pneumoniae and multi drug P. aeruginosa showed high significance in hospital acquired infections. The logistic regression, showed a significant relationship between resistant bacteria and age (p<0.001, ORa=5.680, CI [2.344; 13.765]) and immunosuppressed state (p=0.003, ORa=3.137, CI [1.485; 6.630]) and an inverse relationship for Chronic Obstructive Pulmonary Disease (COPD) (p=0.006, ORa=0.403, CI [0.212; 0.765]). CONCLUSION: Our results confirm that hospital acquired infections/bacteria have higher rates of resistance when compared to community acquired; these rates increase with age, immunosuppression and are inversely proportional with COPD. Therefore, physicians should be aware of patients' comorbidities to properly guide initial therapy.< Leer menos