qPCR-based Bio-burden Testing of Duodenoscopes

qPCR-based Bio-burden Testing of Duodenoscopes qPCR-based Bio-burden Testing of Duodenoscopes Nosocomial infections with carbapenem-resistant Enterobacteriaceae (CRE) have been reported in several healthcare facilities. In the United States, outbreaks of CRE transmission through duodenoscopes have been reported in patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) despite adherence to endoscope reprocessing guidelines[1-4]. This is a substantial public health and patient concern as approximately 500,000 ERCPs are performed annually in the US. Monitoring endoscope disinfection through culture is labor-intensive, time consuming, and prone to false positives due to non-pathogenic environmental contaminants[6].. Some endoscopy units are routinely performing ethylene oxide sterilization of all duodenoscopes, which adds substantial expense and may damage the endoscope. Developing and validating real-time monitoring methods to detect bacterial pathogens on reprocessed endoscopes and assess the risk of infection has been identified as a critical unmet need[3]. We (LaBaer laboratory) are currently developing qPCR-based, sensitive, diagnostic methods for detecting radiation exposure in people by measuring the expression of rare genes from a sample of 10 to 100 blood cells. We propose adapting this novel technology to address an important clinical problem. Our overall aim is to develop a qPCR-based sensitive method for testing duodenoscopes in 2-3 hours, compared to the current 2-3 days. Culture and qPCR are the methods used for quantifying microorganisms in different conditions[5]. We aim to use DNA intercalating agent(s) together with qPCR reaction to discriminate and count both live and dead bacteria, pathogens and viruses simultaneously from endoscope-derived samples. We will use rRNA and other species-specific TaqMan assays to detect different bacteria, pathogens and viruses. Such an assay will be clinically applicable and vastly improve practice efficiency and resource utilization in high-throughput endoscopy units.