Obiakor, C. V.

The Association Between Early Life Antimicrobial Exposure and C. difficile Colonization in Infants
Obiakor, C.V., Parks, J., Takaro, T.K., Tun, H.M., Morales-Lizcano, N., Konya, T.B., Guttman, D.S., Becker, A.B., Azad, M.B., Lefebvre, D.L., Mandhane, P.J., Moraes, T.J., Sears, M.R., Turvey, S.E., Subbarao, P., Scott, A.J., & Kozyrskyj, A.L.

In adults and older children, Clostridioides difficile (C. difficile) is the major pathogen responsible for antibiotic-induced diarrhea but it's presence in infants is unclear. Infants colonized with C. difficile usually do not present with infection or diarrhea. However, colonization with this bacterium in infancy has been linked to development of asthma and allergy in childhood. The aim of this study was to determine the cumulative impact from antibiotics and environmental antimicrobials (household cleaning products) on C. difficile colonization in infants.

This study included a representative sample of mothers and infants (N=1429) from the Canadian Healthy Infant Longitudinal Development (CHILD) cohort. Infant antimicrobial exposure was obtained from birth chart and standardized questionnaires. Fecal samples were collected at 3 months and C. difficile was analyzed using qPCR. Logistic regression analysis was used to determine the association between antimicrobial exposure and C. difficile colonization.

In our study, 44% of infants were exposed to maternal intrapartum antibiotic, 8% received an antibiotic and 47% lived in households with higher use of cleaning products by 3 months. Infants were grouped depending on antimicrobial exposure: no antibiotics and lower cleaning (NALC), any antibiotics and lower cleaning (AALC), no antibiotics and higher cleaning (NAHC), any antibiotics and higher cleaning (AAHC). Compared to NALC infants the odds of C. difficile colonization was 38% higher in AALC infants (p=0.047), 52% higher in NAHC infants (p=0.011) and 103% higher in AAHC infants (p<0.001). After adjusting for covariates, the increased odds of C. difficile colonization remained significant in AAHC infants (aOR 1.50 95%CI 1.03-2.17; p=0.032).

Our study suggests that cumulative exposure to antibiotics and household cleaning products is not without consequence. Hence, the effect of antimicrobial exposure on the infant gut should be considered because colonization with C. difficile may be a marker for future asthma and allergy.