Gastrointestinal Infections in IBD Flares: Can PCR-Based Stool Tests Differentiate the Smoke from the Fire?

Excerpt

Gastrointestinal (GI) infections are a major cause of morbidity and mortality worldwide [1, 2]. In the past, the diagnosis of infective pathogens was accomplished via microscopic examination or culture of, or detection of coproantigens in stool samples. These methods are limited by a lengthy turnaround time, poor sensitivity, a requirement for experts in microscopy, difficulty in isolating non-bacterial agents, and the influence of preanalytical factors such as antibiotics. Using these conventional methods and owing to infrequent detection, non-Clostridioides difficile enteric infections were thought to be minor contributors to the pathogenesis and the disease course of inflammatory bowel disease (IBD) [3, 4]. While multiple studies have supported the involvement of C. difficile toward exacerbations of IBD, with a cross-sectional prevalence up to 16% during an acute flare, far less is known about non-C. difficile pathogens [5]. Recently, rapid and highly sensitive stool molecular multiplex polymerase chain reaction (PCR) panel assays, or GI pathogen panels (GPPs) have replaced relatively insensitive culture-dependent methods for the detection of enteric pathogens in clinical practice. GPPs enable the simultaneous qualitative detection and identification of nucleic acids from multiple bacteria, viruses, and parasites directly from stool samples in Cary Blair transport medium obtained from individuals with signs and/or symptoms of GI infection. Using this technology, there has been renewed interest in the impact of enteric pathogens on IBD pathogenesis beyond C. difficile. …