Association between Chlamydia pneumoniae antibodies and wheezing in young children and the influence of sex

Abstract

Background: The proposed association between Chlamydia pneumoniae (Cpn) infection and wheezing needs further clarification. Methods: Serum samples obtained from 1581 children aged 4 years in a population based cohort were tested for antibodies to Cpn and IgE antibodies to common allergens. Data on environmental factors and disease were collected prospectively from birth. Results: The occurrence of IgG antibodies to Cpn at 4 years of age was associated with reported wheezing at different ages; however, these findings were most often not significant. In girls, the occurrence of antiCpn IgG was associated with wheezing at the ages of 1, 2, and 4 years (odds ratios (ORs) 3.41 (95% confidence interval (CI) 1.46 to 7.96), 2.13 (95% CI 1.02 to 4.44), and 2.01 (95% CI 1.14 to 3.54), respectively), and even higher ORs were observed for each age category when only high level antibody responses to Cpn were analysed. At the time of blood sampling the association between anti-Cpn IgG and wheezing was restricted to girls without atopic sensitisation (OR 2.39 (95% CI 1.25 to 4.57). No associations with wheezing were detected in boys, in whom IgE sensitisation was inversely associated with the presence of anti-Cpn IgG (OR 0.49 (95% CI 0.26 to 0.90). Conclusions: This study suggests an association between evidence of earlier Cpn infection and a history of wheezing in young girls. Infection with Cpn may be an important risk factor for wheezing and possibly for non-atopic asthma, predominantly in girls.

Risk factors for non-atopic asthma/wheeze in children and adolescents: a systematic review

“…Consistent and strong associations with the risk of non-atopic asthma were observed only for 3 factors: family history of asthma, rhinitis or eczema [14,17-23], dampness or mold in the household [17,19,22-25], and lower respiratory infections in childhood [14,17,18,28,29]. A brief period or no breastfeeding also showed a strong, albeit less consistent, association.…”

A clinically silent respiratory infection withChlamydophilaspp. in calves is associated with airway obstruction and pulmonary inflammation

“…The phenomenon of chronicity and persistence, however, is thought to be involved in the pathogenesis of chronic inflammatory airway diseases, i.e. human asthma and COPD, and even in pulmonary emphysema or lung cancer [2,3,14,19,22,26,50,51,56].…”

Nasopharyngeal bacterial colonization during the first wheezing episode is associated with longer duration of hospitalization and higher risk of relapse in young children

“…Evidence of bacteria in the upper airways of children has been found using culture or serology in up to 40% of wheezing children (4)(5)(6). These have included Streptococcus pneumoniae (S Pne),…”