Investigation of Intestinal Microbiota and Fecal Calprotectin in Non-Toxigenic and Toxigenic Clostridioides difficile Colonization and Infection

In this study, we aimed to evaluate the composition of the intestinal microbiota and level of fecal calprotectin in Clostridioides difficile-colonized patients. We included 102 C. difficile non-colonized (group I), 93 C. difficile colonized subjects (group II), and 89 diarrhea patients with C. difficile (group III). Chao1 index for alpha diversity and principal coordinate analysis was performed for beta diversity using QIIME. The mean relative abundance in each group was compared at the phylum and genus levels. Fecal calprotectin was measured using EliA calprotectin (Thermo Fisher Scientific). Group II showed significantly lower levels of Sutterella, Blautia, Ruminococcus, Faecalibacterium, Bilophila, and Ruminococcaceae and higher levels of Enterobacteriaceae compared to group I (p = 0.012, 0.003, 0.002, 0.001, 0.027, 0.022, and 0.036, respectively). Toxigenic C. difficile colonized subjects showed significantly lower levels of Prevotella, Phascolarctobacterium, Succinivibrio, Blautia, and higher levels of Bacteroides. The level of fecal calprotectin in group III was significantly higher than those in group I and group II (p < 0.001 for both). These data could be valuable in understanding C. difficile colonization process and the microbiota and inflammatory markers could be further studied to differentiate colonization from CDI.