Microbiome and Atopy in Mali

Not yet recruiting

• Conditions: Atopic Disease

• Registration Number: NCT07051902
• Lead Sponsor: National Institute of Allergy and Infectious Diseases (NIAID)

Brief Summary

This study is about allergic diseases in people living in Mali. Allergic diseases can cause health problems like asthma or skin rashes. In this study, we will look for clues about things that may affect whether people get allergic diseases. We will look at things on or in the body, like germs, and things in the environment, like pollution. To do this, we will collect different types of biological samples, health information, and environmental information from people with allergic diseases and people without allergic diseases. We will compare what we find in each group to look for differences that might be related to allergic disease.

Detailed Description

This is a case-control study where participants from Bamako in Mali will be screened to identify patients with atopic disease (asthma and atopic dermatitis). Age and sex-matched healthy controls will be selected at a 1:1 ratio. All study participants (including healthy controls) will undergo a clinical evaluation and provide skin swabs, nasal swabs, induced sputum (if successful), blood samples, drinking water samples, stool samples, as well as complete an interviewer-administered questionnaire on environmental exposures. All participants (including healthy controls) will also undergo pulmonary function testing (spirometry and/or oscillometry) and undergo testing of transepidermal electrical impedance (using a Nevisense machine). Samples will be used to evaluate the microbiome diversity in participants with allergy-related diseases (ARDs) compared to healthy controls. Environmental surveys will assess the association between atopy and exposures that are primarily outdoor versus indoor exposures. Temporal and spatial variation in these pollutants will be assessed. Air samples taken from the community and participant home drinking water samples (when available) will be used to assess the presence and variability of pollutants in the environment.

Study Timeline

• Status Verified: 2025-06
• Study First Submitted: 2025-06-26
• Study First Submitted QC: 2025-06-26
• Last Update Submitted: 2025-06-26
• Study First Posted: 2025-07-04
• Last Update Posted: 2025-07-04
• Study Start: 2025-08-01
• Primary Completion: 2026-08
• Study Completion: 2026-08-01

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: All
• Target Recruitment: 288

Inclusion Criteria

Not provided

Exclusion Criteria

• Use of antibiotics in the 3 months prior to screening.
• Current pregnancy or lactation (determined by self-report).
• Treatment with an investigational drug within 12 months prior to screening.
• Current smoker or tobacco use within 4 months prior to screening.
• Current skin infections other than atopic dermatitis (e.g., scabies).
• Active diarrhea as defined by three or more loose stools per day (Bristol stool scale score of 6 or 7).
• Presence of current bacterial, viral, or fungal infection, with the exception of isolated onchomycosis, which is not exclusionary.
• Any other condition or factor that the investigator determines may significantly influence the results of testing.

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Differences in gut microbiome between atopic patients and healthy controls in children and adults.	Within 28 days after the screening visit.	Shannon diversity index analyzed using t-test with significance level of .05.

Secondary Outcome Measures

Name	Time	Method
Relative abundance of taxa and expression of metabolically functional genes in the skin microbiome.	Within 28 days after the screening visit.	RNAseq
Relative abundance of taxa and expression of metabolically functional genes in the gut microbiome.	Within 28 days after the screening visit.	Metagenomic sequencing
Relative abundance of taxa and expression of metabolically functional genes in the nasal microbiome	Within 28 days after the screening visit.	Metagenomic sequencing
Presence, frequency, and/or proximity to environmental exposures.	Within 28 days after the screening visit.	Patient survey
Serum concentration of total IgE, specific IgE panels, and eosinophils	Within 28 days after the screening visit.
Concentration of pollutants or pollutant biomarkers in urine and serum	Within 28 days after the screening visit.

Trial Locations

Locations (2)

Dermatology Hospital of Bamako; 🇲🇱 Bamako, Mali

Pneumology Ward, Point G University Hospital; 🇲🇱 Bamako, Mali