Nosocomial pneumonia (NP) occurs frequently and is associated with inc
reased morbidity and mortality. Its diagnosis, however, is difficult.
The combination of clinical, radiographical and microbiological criter
ia may overestimate the true incidence of the infection. Although rece
ntly introduced techniques, such as bronchoscopy, probably increase th
e specificity for diagnosing NP, it remains to be established whether
the use of these techniques improves patient outcome or decreases unne
cessary antibiotic use.