Antibiotic resistance in nosocomial pulmonary pathogens

Nosocomial pneumonia is the second most common hospital-acquired infection and are associated with antibiotic-resistant microrganisms. In nosocomial p neumonia, both the diagnosis of the disease and the identification of the p athogen agent are controversial. The lack of standard diagnostic criteria c an lead to the inappropriate use of broad-spectrum antibiotic therapy and t he emergence of multiresistant bacteria. Moreover, empirical antibiotic tre atment must be prescribed after bacteriological sample but before culture r esults because the majority of nosocomial pneumonias require an urgent anti biotic therapy. Most nosocomial pneumonias are of an endogenous origin, par ticularly in mechanically ventilated patients, and this is associated with a higher rate of multiresistant methicillin-resistant Staphylococcus aureus , Acinetobacter baumanii, Klebsiella pneumoniae with extended spectrum b-la ctamases, and Pseudomonadaceae. Multiple factors influence the frequency of pathogens associated with antibiotic resistance, such as duration of hospi tal stay, time of onset, prior antibiotic therapy, and local microbial ecol ogy.