Some new research into why FMT fails for some people:

“Although [FMT] is a powerful therapy for individuals who develop recurrent CDI (rCDI), 10% to 15% of patients still fail to recover following FMT”

Researchers have identified a number of risk factors for treatment failure after fecal microbiota transplantation (FMT) for Clostridioides difficile infection (CDI), some of them modifiable.

“In univariate analyses, poor cleansing of the transverse colon (P=0.043) and narcotic use were significant predictors of rCDI after successful FMT (P=0.039).”

“In multivariate analyses, the presence of diabetes predicted initial FMT failure (odds ratio [OR], 0.03; 95% CI, 0.001-0.81), and failure to deliver transplanted stool to the terminal ileum predicted rCDI after initial success (OR, 0.81; 95% CI, 0.66-0.99).”

“Of 26 different risk factors identified in the studies, the current meta-analysis identified inpatient FMT administration (OR, 5.2; 95% CI, 3-8.92), older age (OR, 1.05; 95% CI, 1.021-1.086) and the presence of IBD (OR, 5.2; 95% CI, 2.53-10.67) as predictors of failure. Other predictors of FMT failure included early antibiotic use after FMT (OR, 4.73; 95% CI, 1.77-12.65), immunosuppression (OR, 3.85; 95% CI, 1.85-8), higher Charlson Comorbidity Index scores (OR, 1.34; 95% CI, 1.1-2.87) and the presence of pseudomembranes at the time of FMT (OR, 4.681; 95% CI, 1.79-12.25).”

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