Neonatal sepsis, antibiotic therapy and later risk of asthma and allergy.

Neonatal sepsis and early antibiotic therapy affect bacterial colonisation and immune activation after birth. This could have implications for later risk of allergy and asthma. Using a validated questionnaire (International Study of Asthma and Allergies in Children, ISAAC), we screened for asthma and allergy in three cohorts (total n = 834; median age 12, range 7-23 years) with different perinatal exposures as regards infection and antibiotics. Asthma, but not hay fever, was more prevalent after neonatal sepsis with adjusted odds ratio (OR) 1.63 [95% confidence interval (CI) 1.04, 2.56] and early antibiotic therapy (OR 1.48 [0.93, 2.35]) as compared with a control group. There was a trend towards increased atopic eczema after neonatal sepsis (OR = 1.39 [CI = 0.98, 1.98]). We conclude that neonatal sepsis is associated with an increased risk for later development of asthma. Early antibiotic exposure may contribute to this association.