Multiplex polymerase chain reaction: Could change diagnosis of Ventilator-associated pneumonia in pediatric critical care units to the fast track?

Abstract

Background: Ventilator-associated pneumonia (VAP) is a frequent hospital-acquired infection in critically ill children. The increasing incidence of infections by antibiotic-resistant pathogens adds significantly to the cost of hospital care and to the length of hospital stays. Besides clinical prerequisites for presumptive diagnosis of VAP, rapid identification of the causative pathogen is essential for appropriate treatment.

Aim of study: To identify the causative bacterial pathogens of VAP by both conventional microbiological cultures and multiplex reverse transcriptase reaction (m-PCR) methods with assessment of turnaround time for both diagnostic modalities together with their diagnostic accuracy.

Methods: Patients were diagnosed to have VAP when their Clinical Pulmonary Infection Score (CPIS) index was more than 6. Endotracheal aspirate was subjected to both microbiological cultures and multiplex PCR for bacterial pathogens.

Results: Multiplex-PCR showed better sensitivity and positive predictive value than bacterial culture for etiological diagnosis of VAP. Acinetobacter and Klebsiella pneumoniae were the most common identified pathogens. Mean turnaround times were 6 h for multiplex PCR and 72 h for conventional microbiology. Significant shorter turnaround time was recorded with m PCR compared to microbiological culture.

Conclusion: Multiplex-PCR permits simultaneous detection of several bacterial pathogens in a single reaction with best turnaround time that permit optimization of emergency diagnosis of VAP and subsequently improve early management of selective bacterial pathogens.

Keywords: m-PCR, Ventilator-associated pneumonia, Bacterial diagnosis, Turnaround time