As you probably already know, the first 1000 days is a really ”critical window” for the development of the infant gut microbiome.

Anything that interferes with the optimal colonistation of the infant gut microbiome may in turn impact the maturation of the infant immune system. This may have consequences for a child's long-term health.

The use of antibiotics in very early life has a huge impact on these microscopic processes.

Antibiotics may affect the optimal "seeding and feeding" of the infant gut microbiome, which in turn may disrupt the maturation of the infant immune system, leading to adverse health outcomes such as atopic disorders.

{Worth noting: The terms atopy and allergy are different: Atopy is an exaggerated IgE-mediated immune response. All atopic disorders are type I hypersensitivity disorders. Allergy is any exaggerated immune response to a foreign antigen regardless of mechanism.}


New research article:

A new research article highlights how antibiotics given to newborn babies can impact their longer-term health.

Published as a Letter to the Editor by Kamphorst K. et al (March 27, 2021), researchers suggests newborn babies exposed to antibiotics for 5-7 days in their first week of life had an almost 3 times higher risk of allergy at age 4-6 years old (as reported by their parents).

The study:

Using data from the INCA study, 151 infants received broad-spectrum antibiotics in their first week of life. These were compared and 285 healthy controls who did not receive broad-spectrum antibiotics.

Previously, scientists showed that antibiotic treatment in the first week of life was associated with an increased risk of wheezing, infantile colic and more allergic sensitisation in the first year of life.

Now in this follow-up study of the group of 418 eligible children, researchers looked at the impact of antibiotics given in the first week on the child's health at 4-6 years old.

The scientists used questionnaires filled out by parents plus information from GPs and local pharmacies.

The results:

The scientists found that children exposed to antibiotics for 5-7 days in the first week had an almost 3 times higher risk of parental reported allergy at age 4-6 years old.

More importantly, this effect was INDEPENDENT of additional antibiotics given up to 2 years.

The conclusion:

"Our findings suggest that very early exposure to AB in the first week of life has a higher impact on immune development than when administered later in childhood."

This article highlights the need for clinicians to be "judicious" in their use of antibiotics for newborn babies, especially with prolonged antibiotic treatment of 5-7 days.

Scientific reference:

Kamphorst, K., Vlieger, A.M., Oosterloo, B.C., Waarlo, S. and van Elburg, R.M. (2021), Higher risk of allergies at 4‐6 years of age aftersystemic antibiotics in the first week of life. Allergy. March 27, 2021


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