Diagnosis of ventilator-associated pneumonia

It is accepted that a definite diagnosis of ventilator-associated pneumonia is difficult to confirm by clinical or radiological features, as different entities can mimic its existence in critically ill patients. Numerous studies have been performed in recent years to find the most accurate technique for obtaining the causal microorganism and for confirming the suspected diagnosis of ventilator-associated pneumonia. However, most of the studies lack a reliable reference test to validate the techniques investigated. Moreover, an open debate exists as to whether non-invasive or invasive techniques are the best choice to diagnose ventilator-associated pneumonia microbiologically. The optimal technique for the diagnosis of ventilator-associated pneumonia remains unclear.