Characterization of pathogens involved in ventilator associated pneumonia in surgical and medical intensive care units - A single center experience.

In the present study 60 samples were collected from lower respiratory tract of patients suffering from Ventilator Associated Pneumonia (VAP) admitted in surgical and medical Intensive Care Units (ICUs) of Khyber Teaching Hospital, Peshawar, Pakistan. Recovered pathogens were characterized and their susceptibility pattern against commonly used antibacterial agents investigated. Most frequent bacterial pathogen found was methicillin- resistant Staphylococcus aureus (MRSA) (40%) followed by members of Enterobacteriaceae (22%; of which Escherichia coli (50%), Klebsiella pneumonia (30%), Enterobacter cloacae (10%) and Citrobacter freundii (10%), Pseudomonas aeruginosa 20% and Acinetobacter baumannii 18%. Majority of the specimens yielded polymicrobial growth (85.75% polymicrobial growth compared to 14.25% specimens yielding monomicrobial growth). The susceptibility pattern showed that A. baumannii was the most resistant bacterial pathogen. Based on the results of susceptibility pattern obtained in the present study, combination of linezolid with meropenem and colistin has been found to be the best combination option for empirical therapy for VAP pathogens in this region.