Lifestyle and Recurrent Clostridioides Difficile Infection (CDI)

Diet for Prevention of Recurrent C. Difficile Infection

This study aims to evaluate the impact of diet on the gut microbiome in adults with Clostridioides difficile infection (CDI). Eligible participants will be randomized and receive meals plus different types of health counseling. Counseling visits will be by phone or online videoconference (e.g. Zoom). Meals will be provided for two weeks and then participants will be asked to continue similar meals for 6 more weeks.

Participants will provide responses to questionnaires and multiple stool samples over the course of the study. The goal is to understand how different health factors might impact the risk of becoming infected again with C. difficile in the future.

Of note, this study will conceal the intervention details (type of diets) so that the control group does not increase their intake with the particular diet during the study. Participants in the control arm will be unblinded at the end of the study during a debrief with a member of the study team. At that time participants will be informed of diet being tested.

Study Overview

• Status: Not yet recruiting
• Conditions: Clostridioides Difficile Infection
• Intervention / Treatment: Other: Diet (experimental diet); Other: Health counseling sessions; Other: Diet (control diet)

• Study Type: Interventional
• Enrollment (Estimated): 20
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Kira Newman, MD, PhD; Phone Number: 734-615-4628; Email: kinewman@med.umich.edu

Study Locations

• United States
  • Michigan
    • Ann Arbor, Michigan, United States, 48109
      • University of Michigan
      • Contact: Kira Newman, MD, PhD; Phone Number: 734-615-4628; Email: kinewman@med.umich.edu
      • Principal Investigator: Kira Newman, MD, PhD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Provision of signed and dated informed consent form
• Stated willingness to comply with all study procedures and lifestyle considerations and availability for the duration of the study
• Non-recurrent non-fulminant CDI (laboratory-confirmed C. difficile infection without prior C. difficile infection within 3 months and no shock, hypotension, ileus, or megacolon)
• Currently receiving treatment or with plan to initiate treatment for CDI
• CDI treatment with standard regimen (fidaxomicin 200milligrams (mg) by mouth (PO) twice a day x 10 days or vancomycin 125mg PO 4 x a day (QID) x 10 days)
• No prior advanced therapy for C. difficile (i.e. prolonged antibiotic therapy, bezlotoxumab, fecal transplant, other microbial therapy)

Exclusion Criteria:

• Chemotherapy, immunotherapy, or transplant within 12 months
• Colon not in continuity (i.e. status post total colectomy or with current ileostomy)
• Medical comorbidities requiring specific fluid, sodium, or protein intake level outside range of prepared diet options
• Baseline diet with > 11grams fiber/1000 kilocalorie
• Low sodium diet, vegan diet, gluten-free diet, Kosher diet or any other diet not able to be accommodated by the metabolic kitchen
• Allergies, food preferences, or other restrictions not able to be accommodated by the metabolic (note: lactose intolerance will not impact eligibility)
• Unwilling to stop probiotic supplements during the study period
• Current antibiotic therapy that will continue after CDI treatment has finished
• Hospitalized or in skilled nursing facility at time of CDI treatment conclusion
• Pregnancy or breast-feeding
• Unable to provide a stool sample of appropriate quality for further analysis (i.e. low volume, adulterated, delayed return, etc.)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Experimental Diet plus health counseling; As stated earlier, the diet and intervention details will not be listed for concealment purposes.	Other: Diet (experimental diet); Participants will receive 2 weeks of prepared meals. Participants will then be asked to follow a similar diet for 6 weeks.
Other: Diet (control diet per protocol) plus health counseling; As stated earlier, the diet and intervention details will not be listed for concealment purposes.	Other: Health counseling sessions; Participant will have two health counseling visits with a member of the study team between weeks 2-8.; Other: Diet (control diet); Participants will receive 2 weeks of prepared meals. Participants will then be asked to follow a similar diet for 6 weeks.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change from baseline to week 2 in alpha-diversity of fecal microbiome by 16S rRNA sequencing	Change from baseline to week 2 (post feeding period) in alpha-diversity of fecal microbiome by 16S rRNA sequencing using Shannon index.	Baseline, 2 weeks (post feeding period)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change from baseline to week 8 in microbiome alpha-diversity (Shannon Index via 16S rRNA)	Measured by Shannon Index via 16S rRNA.	baseline to week 8
Incidence of recurrent CDI	Laboratory-confirmed symptomatic infection requiring treatment.	baseline to week 8
Change in CDI-related Quality of Life (QOL) baseline to Week 8	Patient-reported health-related quality of life assessed using the Clostridioides difficile Quality of Life Survey (Cdiff32) total score (range 0-100; higher scores indicate better quality of life).	Baseline to Week 8
Tolerability of diet based on the mean percent of meals consumed during the first 2 weeks	This is during the 2-weeks of receiving provided meals.	2 weeks (during the provided meal period)

Collaborators and Investigators

• Sponsor: University of Michigan
• Collaborators: Michigan Nutrition Obesity Research Center
• Investigators: Principal Investigator: Kira Newman, MD, PhD, University of Michigan

Study record dates

Study Major Dates

• Study Start (Estimated): June 1, 2026
• Primary Completion (Estimated): June 1, 2027
• Study Completion (Estimated): June 1, 2027

Study Registration Dates

• First Submitted: May 21, 2026
• First Submitted That Met QC Criteria: May 21, 2026
• First Posted (Actual): May 29, 2026

Study Record Updates

• Last Update Posted (Actual): May 29, 2026
• Last Update Submitted That Met QC Criteria: May 21, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Diet; Surveys; Stool samples; Health counseling
• Additional Relevant MeSH Terms: Infections; Gram-Positive Bacterial Infections; Bacterial Infections; Bacterial Infections and Mycoses; Clostridium Infections; Diet, Food, and Nutrition; Physiological Phenomena; Nutritional Physiological Phenomena; Diet
• Other Study ID Numbers: HUM00284257

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No