Multicenter Evaluation of the Unyvero Platform for Testing Bronchoalveolar Lavage Fluid

Bronchoalveolar lavage (BAL) culture is a standard, though time consuming, approach for identifying microorganisms in severe lower respiratory tract infections. Sensitivity of BAL culture is relatively low and prior antimicrobial therapy decreases the sensitivity further, leading to overuse of empiric antibiotics. The Unyvero LRT BAL Application (Curetis GmbH, Germany) is a multiplex molecular panel that detects 19 bacteria, 10 antibiotic resistance markers and a fungus, Pneumocystis jirovecii, in BAL fluid in ∼4.5 hours. Performance was evaluated using 1,016 prospectively collected and 392 archived specimens from 11 clinical trial sites in the United States. Overall positive and negative percent agreement with culture for identification of bacteria that grow in routine cultures were 93.4% and 98.3%, respectively, with additional potential pathogens identified by Unyvero in 21.7% of prospectively collected specimens. For detection of P. jirovecii, positive percent agreement with standard testing was 87.5%. Antibiotic resistance marker results were compared to standard antibiotic susceptibility testing to determine positive predictive values (PPVs). PPVs ranged from 80-100%, based on the microorganism and specific resistance marker(s). The Unyvero LRT BAL Application provides accurate detection of common agents of bacterial pneumonia and of P. jirovecii. The sensitivity and rapidity of this panel suggests significant clinical value for choosing appropriate antibiotics and for antibiotic stewardship.