Clostridium difficile infection (CDI) is a common infection in which alterations in gut microbiota play an important role in increased susceptibility. Although current research is assessing several clinical features that may predict CDI treatment response, there is a need for consistent predictors of response and recurrence in patients with a first occurrence of CDI.

A recent study, led by Dr. Purna C. Kashyap from the Division of Gastroenterology and Hepatology at Mayo Clinic in Rochester (USA), has found that gut microbiota signatures may allow identification of patients with Clostridium difficile infection who will respond to initial treatment.

The researchers prospectively recruited 88 patients (median age 52.7 years) with their first CDI episode and collected pre-treatment stool samples and clinical data.

Treatment failure occurred in 12.5% following the recommended treatment with either metronidazole or vancomycin. Patients who initially responded to treatment (responders) had an increase in Ruminococcaceae, Rikenellaceae, Clostridiaceae, Bacteroides, Faecalibacterium and Rothia compared to nonresponders. A risk index built from this panel of microbes allowed differentiation of responders from nonresponders. These data suggest that gut microbiota signatures prior to treatment may predict response to therapy in CDI. Besides this, among the patients who initially responded to treatment, 28.5% went on to experience another infectious episode (recurrent CDI). Patients with recurrent CDI after successful treatment had an increase in Veillonella, Enterobacteriaceae, Streptococci, Parabacteroides and Lachnospiraceae compared to patients without recurrence after treatment. A risk index built from this panel of microbes differentiated between patients with and without recurrence.

Corroborating the findings about gut microbiota composition, results showed the gut microbiota functional repertoire was significantly different in responders and nonresponders and in those with and without recurrence.

In conclusion, the initial response to treatment and recurrence after successful treatment in patients with primary CDI could be predicted by the presence of a specific panel of microbes. These microbial signatures could potentially be used for identifying subsets of patients that may benefit early from conventional therapies for CDI.



Khanna S, Montassier E, Schmidt B, et al. Gut microbiome predictors of treatment response and recurrence in primary Clostridium difficile infection. Aliment Pharmacol Ther. 2016; 44(7):715-27. doi: 10.1111/apt.13750.