Results: The causes of bacterial pneumonia in mechanically ventilated patients: Acinetobacter baumannii 56 (25.4%), Klebsiella pneumoniae 42 (19.2%), Staphylococcus aureus 40 (18.1%), Pseudomonas aeruginosa 34 (15.4%), Escherichi coli 26 (11.8%), Enterobacter cloace 22 (10.1%).