Comorbid status and the faecal microbial transplantation failure in treatment of recurrent Clostridioides difficile infection – pilot prospective observational cohort study

Background Faecal microbial transplantation (FMT) is currently the most effective treatment of recurrent Clostridioides difficile infection (CDI). However, up to 20% of patients experience further recurrences after single FMT. The mechanisms that lead to FMT failure and its risk factors are poorly understood. Comorbidity is one of the risk factors of the failure of standard antibiotic therapy of recurrent CDI. It is not known if comorbidity is also associated with the risk of FMT failure. Methods We conducted a prospective observational cohort study in order to elucidate if comorbid status is associated with FMT failure. Patients with microbiologically proven recurrent CDI were recruited and underwent FMT via retention enema. Patients were followed up for 12 weeks after FMT for signs and symptoms of CDI recurrence. Single FMT failure was defined as recurrence of diarrhoea and a positive stool test for the presence of C. difficile antigen or toxin at any time point during the 12 weeks of follow-up. We assessed the association of single FMT failure with possible manageable and unmanageable risk factors. As a surrogate of comorbid status, we used Charlson Comorbidity Index (CCI) ≥ 7. Results A total of 60 patients that underwent single FMT (34 women, 26 men) were included in the study. Overall, 15 patients (25%) experienced single FMT failure. 24 patients (40%) had CCI ≥ 7, and 45.0% patients with CCI ≥ 7 experienced failure of single FMT. Patients who experienced single FMT failure had a significantly higher CCI and significantly lower albumin concentration as compared to patients who experienced single FMT success. There was no difference in age, C-reactive protein concentration, leukocyte count and time from FMT to first defecation. In multivariate analysis, CCI ≥ 7 was positively associated with the failure of single FMT. Analysis was controlled for sex, age, time from FMT to first defecation, concomitant PPI therapy, severe CDI, hospital-acquired infection and albumin concentration. Conclusions Comorbid status surrogated by CCI is positively associated with the failure of single FMT in the treatment of recurrent CDI.