Study on the Association Between Vitamin C Deficiency and Diarrhea in Children

Diarrheal disease is the second leading cause of death in children under five, althought it is both preventable and treatable. The causative factors of diarrheal diseases vary a lot from region to region (bacteria, viruses, parasites). Diarrhea is one of the main causes of malnutrition in children under five years of age. Inversely, nutritional deficiency, particularly vitamin C deficiency, can be a risk factor for diarrhea.

The main objective of this study is to assess the impact of vitamin C deficiency on diarrheal infection in children aged 2 to 5 years in countries with a high diarrheal rate. This pilot case-control study will be conducted in metropolitan France, Africa and South America. This question will be addressed by comparing vitamin C levels in children with diarrhea, regardless of the infectious agent, to levels in age- and sex-matched controls.

The study aims at (i) determining whether vitamin-deficiency may occurs in children living in developing countries and at (ii) determining the plasma vitamin A, C and E concentrations in children suffering of diarrheal diseases.

A total of 360 children will participate to the study.

Controls :

Inclusion criteria

• not suffering of diarrhea
• no fever
• no sign of infection

Exclusion criteria

• Suspected or diagnosed infectious diseases
• Known genetic diseases
• Known diseases that may interfere with iron and/or vitamin C metabolism
• Known inflammatory diseases
• Malnutrition
• Diarrhea
• Fever
• Positive malaria rapid diagnostic test (Africa)
• Child currently being breastfed

Chronic diarrhea cases :

Inclusion criteria

-Children suffering from chronic diarrhea defined by the emission of at least 3 soft or liquid stools per day for at least 4 weeks.

Exclusion criteria

• Suspected or diagnosed infectious diseases
• Known genetic diseases
• Known diseases that may interfere with iron and/or vitamin C metabolism
• Known inflammatory diseases
• Positive malaria rapid diagnostic test (Africa)
• Antibiotic treatment prescribed within 10 days prior to sampling
• Nutritional supplements in the three months prior to sampling
• Vitamin C supplementation in the last 3 months prior to blood collection
• Child currently being breastfed

Acute diarrhea cases :

Inclusion criteria

-Children suffering from acute diarrhea defined as 3 or more loose or watery stools per day for at least 3 consecutive days and up to 10 consecutive days.

Exclusion criteria

• Malnutrition
• Suspected or diagnosed infectious diseases
• Known genetic diseases
• Known diseases that may interfere with iron and/or vitamin C metabolism
• Known inflammatory diseases
• Positive malaria rapid diagnostic test (Africa)
• Antibiotic treatment prescribed within 10 days prior to sampling
• Nutritional supplements in the three months prior to sampling
• Vitamin C supplementation in the last 3 months prior to blood collection
• Child currently being breastfed