A 60 year old male patient admitted in ICU develops fever and productive cough 48 hours after admission in the hospital. Which of the following is the most common causative organism?: (A) Mycoplasma, (B) Pseudomonas, (C) Staphylococcus, (D) Hemophhilus Influenza
Answer is B. Hospital acquired pneumonia is polymicrobial in origin and is most commonly caused by gram negative bacilli such as Pseudomonas, Klebsiella and E coli. Other causative organisms inlcudes anaerobic bacteria and Staphyloccoccus aureus.