Rapid identification of Staphylococcus aureus in bronchoalveolar lavage fluid using a DNA probe (Accuprobe).

Staphylococcus aureus is one of the prominent causative agents of ventilator-associated pneumonia (VAP). Gram staining of bronchoalveolar lavage (BAL) fluid is not always reliable. A nonisotopid probe (Accuprobe) has been developed by Gen-Probe for the specific identification of S. aureus isolated from cultures. This study was undertaken to assess the reliability of this probe for the early diagnosis of S. aureus VAP.A prospective study in 120 consecutive patients.Department of intensive care medicine at a university hospital.120 ventilated patients (70 males and 50 females; mean age 52 +/- 12 years; mean simplified acute physiologic score = 13 +/- 4) were studied.164 bronchoalveolar lavages were performed (none of the patients received prior antibiotic therapy).S. aureus was identified 29 times at significant concentrations (> or = 10(4) cfu/ml) and 7 times at < 10(4) cfu/ml. The sensitivity and specificity of the Accuprobe system were 100 and 96%, respectively. We found agreement between quantitative cultures and probes in 96.3% of cases.We conclude that this probe provides a rapid (< or = 7 h) and accurate diagnosis of S. aureus pulmonary infection.