For a study, it was determined that there was mounting evidence that the large intestine microbiota influences the risk of colon cancer, as well as other disorders such as type 1 diabetes, inflammatory bowel disease, and irritable bowel syndrome. Obtaining microbiological specimens using current sample procedures, such as feces and mucosal biopsies, was cumbersome and unattractive to patients. Rectal swabs could be a faster and easier way to collect samples, but it’s uncertain if they were a good substitute. The researchers investigated the bacterial diversity and composition of rectal swabs with rectal mucosal biopsies to determine if rectal swabs may be used instead of biopsies. In un-prepped subjects (n=11), paired rectal swabs and mucosal biopsy samples were taken, and microbial diversity was determined using Terminal Restriction Fragment Length Polymorphism (T-RFLP) analysis and quantitative polymerase chain reaction (qPCR) of the 16S rRNA gene. Swab samples had a distinct microbial community composition than rectal mucosal biopsies (P=0.001). As measured by diversity indexes such as richness (P=0.01), evenness (P=0.06), and Shannon’s diversity (P=0.04), bacterial diversity was higher in swab samples than in biopsies. qPCR analysis of certain bacterial families revealed that swab samples had greater copy numbers of Lactobacillus (P<0.0001) and Eubacteria (P=0.0003) than biopsies.
Link:www.tandfonline.com/doi/full/10.4161/gmic.22157