[Quantitative culture sampling of tracheal aspirates for diagnosis of nosocomial pneumonia in the ITU]

Nosocomial pneumonia is defined as a pneumonia developing within 48 hours of admission, in a patient with previously normal lung tissue. Ventilator-associated pneumonia (VAP) due to migration of microorganisms from the nose, throat and digestive tract is typical in ITU patients. Microbiological diagnosis is difficult, and there is no single method approved for VAP diagnosis. We have assessed the usefulness of Quantitative Endotracheal Aspirate (QETA) for this purpose, basing on its reported high sensitivity (mean 76% +/- 9%) and specificity (mean 75 +/- 28%).Endotracheal aspirates were sampled from ITU patients fulfilling the following criteria: (1) New or progressive infiltrations in the lungs plus hyperthermia (38.3 degrees C) or hypothermia (36 degrees C); (2) leukocytosis (12 G L(-1)) or leukopenia (4 G L(-1)); or (3) purulent sputum.Nosocomial pneumonia was diagnosed in 40 out of 312 patients treated in the ITU during the study period. VAP was diagnosed in 33 patients. Multi-drug resistant bacteria: Pseudomonas aeruginosa (16), Acinetobacter baumannii (19), ESBL pathogens (8) and MRSA (1) were cultured from QETA in 32 patients. The sensitivity of QETA was 86%.The results allowed for early and accurate diagnosis of nosocomial pneumonia and institution of the best possible treatment.