Going back to prospectively collected results with a probiotic for primary prevention of Clostridium difficile infection at a tertiary-care medical center

A detailed metagenomics analysis by Raymond et al3 of stool samples from healthy volunteers taking an antibiotic uncovered consistent impairments to the diversity and functioning of the gut microbiota and enrichment of resistance genes. The case-control study did not detect a protective effect, but results from the same cohort presented in 2015 indicate a reduced risk of CDI in patients treated with this probiotic.4 A risk ratio of 0.6 (95% CI, 0.4–0.9; P=.01) was calculated, representing a significant protective effect from C. difficile infection for the probiotic recipients (Fig. 1). The inputs for this equation are based on the principal data set collected prospectively within the design of the study, and as such, they do not rely on detailed electronic patient records. [...]these prospectively collected data suggest that the intervention was having the intended effect.