ABSTRACT
Ventilator associated pneumonia [VAP] is defined as pneumonia occurring after the first 48 hours of starting mechanical ventilation. The incidence of VAP varied between 7-70% in different studies. The pathogenesis of VAP usually requires the occurrence of two important processes: bacterial colonization of the aerodigestive tract and the aspiration of contaminated secretion into the normally sterile lower respiratory tract. The principal promise of bronchoscopy for the diagnosis consists of the ability to retrieve uncontaminated lower respiratory secretions and consequently doing quantitative cultures, this should allow a valid differentiation of colonization from infection. The aim of this study was to determine the role of legionella species, mycoplasma pneumoniae, Chlamydia pneumoniae, mycobacterium tuberculosis, fungi, and anaerobes as etiologic agents of VAP and to compare between quantitative Endotracheal Aspirate [EA] and bronchoalveolar lavage[BAL] techniques for the diagnosis of VAP. The study was conducted on 30 patients admitted to the critical care medicine department of Alexandria main university hospital who required invasive mechanical ventilation for at least 48 hours and developed clinical manifestations of VAP. Gram negative bacteria were the most common etiologic pathogens, followed by atypical bacteria. There was no statistically significant difference between both EA and BAL regarding the aetiologic pathogens