['clostridium difficile', 'pseudomembranous colitis']
['vancomycin (before randomization)']

        Inclusion criteria:

          -  Recurrent C. difficile infection (identified by positivity of C. difficile toxin in
             stools) with severe clinical picture (defined by the ESCMID Guidelines published in
             2014 - Debast et al, Clin Microbiol Infect 2014)

          -  Possibility to undergo standard antimicrobial therapy for recurrent C. difficile
             infection Approval of informed consent

          -  Possibility to undergo protocol diagnostic and therapeutic procedures

          -  Stool negativity for parasites

          -  Stool negativity for Salmonella spp., Shigella spp., Yersinia enterocolitica,
             Campylobacter, Streptococcus agalactiae, Staphylococcus aureus, enteropathogenic
             Escherichia coli and other microorganisms except for C. difficile

          -  Blood negativity for: Hepatitis A virus-Immunoglobulin M, HBsAg, Anti-Hepatitis C
             Virus, Anti-Human Immunodeficiency Virus1-2, venereal disease reaction level (VDRL).

        Exclusion Criteria:

          -  Subjects <18 years old

          -  Prior colectomy

          -  Negativity of C. difficile toxin in stools

          -  Mild clinical picture of C. difficile infection

          -  High risk of post-colonoscopy complications

          -  Other main gastrointestinal diseases (es. Crohn's disease or ulcerative colitis)

          -  Stool positivity for parasites

          -  Stool positivity for Salmonella spp., Shigella spp., Yersinia enterocolitica,
             Campylobacter, Streptococcus agalactiae, Staphylococcus aureus, enteropathogenic
             Escherichia coli and other microorganisms except for C. difficile

          -  Blood positivity for: Hepatitis A virus-Immunoglobulin M, HBsAg, Anti-Hepatitis C
             Virus, Anti-Human Immunodeficiency Virus1-2, venereal disease reaction level (VDRL).

          -  Pregnancy or breastfeeding.

          -  Inability to follow protocol procedures
      