Comparative Analysis of Fecal Short Chain Fatty Acids Profiles in Atopic Dermatitis And Healthy Infants

RATIONALE: Short chain fatty acids (SCFAs) are intermediate and end products of metabolism of dietary fibre by intestinal commensal bacteria, and regulate the host’s immune function. The aim of this study was to evaluate and compare fecal SCFAs profiles in infants with atopic dermatitis (AD) and healthy controls.

METHODS: From Growing Up in Singapore Towards healthy Outcomes (GUSTO) cohort, a subcohort of 64 subjects were recruited and categorized into three clinical groups: (1) non-allergen sensitized AD (n=15), (2) allergen sensitized AD (n=14) and (3) healthy controls (n=35). A total of 164 fecal samples were collected at week 3, month 3, 6 and 12 and quantitated for acetic, propionic, butyric, isobutyric, valeric, isovaleric, 2-methylbutyric, caproic and 4-methylvaleric acids by liquid chromatography tandem mass spectrometry. Longitudinal multivariate analysis was employed to study the dynamic trends of SCFAs, while adjusted for possible confounders (gender, presence of siblings, mode of delivery, feeding pattern, use of pre-natal antibiotics and family history of atopic diseases).

RESULTS: All fecal SCFAs levels except for caproic and 4-methylvaleric acids increased with age in all three clinical groups. Decreased acetic, propionic and butyric acid levels were significantly associated with allergen sensitized AD compared to controls, but not with non-allergen sensitized AD (adj p<0.05). The other SCFAs did not show significant differences between groups. Clinical determinants of SCFAs levels included presence of siblings, use of pre-natal antibiotics and family history of atopic diseases (adj p<0.05).

CONCLUSIONS: Fecal SCFAs may play a role in the development of AD with allergen sensitization.