CD79A and clostridium difficile infection: In a study of active CDI in 24 patients, the infecting strains of C. difficile were the dominant fraction of IgA-coated bacteria, while strains belonging to Clostridium cluster IV (Eubacterium, Ruminococcus and Anaerofilum genera) and Lactobacillales order showed decreased IgA-coating [54].