PT  - JOURNAL ARTICLE
AU  - Emmy Van Daele
AU  - Kim Kamphorst
AU  - Arine M Vlieger
AU  - Gerben Hermes
AU  - Christian Milani
AU  - Marco Ventura
AU  - Clara Belzer
AU  - Hauke Smidt
AU  - Ruurd M van Elburg
AU  - Jan Knol
TI  - Effect of antibiotics in the first week of life on faecal microbiota development
AID  - 10.1136/archdischild-2021-322861
DP  - 2022 May 09
TA  - Archives of Disease in Childhood - Fetal and Neonatal Edition
PG  - fetalneonatal-2021-322861
4099  - http://fn.bmj.com/content/early/2022/05/08/archdischild-2021-322861.short
4100  - http://fn.bmj.com/content/early/2022/05/08/archdischild-2021-322861.full
AB  - Background Infants are frequently exposed to antibiotics (AB) in the first week of life for suspected bacterial infections. Little is known about the effect of AB on the developing intestinal microbiota. Therefore, we studied intestinal microbiota development with and without AB exposure in the first week of life in term born infants.Methods We analysed the faecal microbiota from birth until 2.5 years of age by 16S rRNA gene amplicon sequencing in a cohort with 56 term born infants, exposed to AB in the first week of life (AB+) (AB for 2–3 days (AB2, n=20), AB for 7 days (AB7, n=36)), compared with 126 healthy controls (AB-). The effects of AB and duration were examined in relation to delivery and feeding mode.Results AB+ was associated with significantly increased relative abundance of Enterobacteriaceae at 3 weeks and 1 year and a decrease of Bifidobacteriaceae, from 1 week until 3 months of age only in vaginally delivered, but not in C-section born infants. Similar deviations were noted in AB7, but not in AB2. After AB, breastfed infants had lower relative abundance of potentially pathogenic Enterobacteriaceae compared with formula fed infants and recovered 2 weeks faster towards controls.Conclusions AB exposure in the first week of life alters faecal microbiota development with deviations in the relative abundance of individual taxa until 1 year of age. These alterations can have long-term health consequences, which emphasises the need for future studies aiming at restoring intestinal microbiota after AB administration.Data are available on reasonable request. The data are available on request with the corresponding author.