Increased risk for bronchitis after discharge in non-vaccinated very low birth weight infants.

BACKGROUND: In very low birth weight (VLBW) infants, obstructive bronchitis is a frequent cause of hospital re-admission. For VLBW infants, early vaccinations starting at 2 months after birth have been recommended. OBJECTIVE: To analyze risk factors for bronchitis during the first year after discharge and the effects of in-hospital standard vaccination (hexavalent/pneumococci) and/or RSV immunoprophylaxis with palivizumab. METHODS: A standardized questionnaire was sent to the parents of VLBW infants 7 month after discharge. The reported episodes of bronchitis were correlated with clinically recorded parameters including risk factors for pulmonary morbidity. The effects of in-hospital vaccination were assessed in a subgroup discharged after day 60. RESULTS: A sample of 1 967 responses of infants born 2009-2011 was analyzed. Risk factors for bronchitis were male gender and older siblings. 24% of the population had episodes of bronchitis. In the subgroup discharged after day 60, episodes of bronchitis were reported for 31% of infants who were not vaccinated in-hospital. A significant reduction of the bronchitis rate was found in infants who received palivizumab±standard vaccination (17% bronchitis, p=0.003). Interestingly, in-hospital standard vaccination without RSV immunoprophylaxis was protective (20% bronchitis; p=0.037) as well. CONCLUSIONS: Non-vaccinated male VLBW infants with older siblings are at increased risk for bronchitis during the first year after discharge. Vaccination according to schedule seems to have protective effects, while underlying mechanisms are unknown. The rate of timely vaccination in preterm infants should be increased.

CD14 promoter polymorphism -159C>T is associated with susceptibility to chronic Chlamydia pneumoniae infection in peripheral blood monocytes.

Chlamydia pneumoniae uses peripheral blood monocytes (PBMC) for systemic dissemination and has been linked to atherogenesis by inflammation mediated via TLR2/4 and CD14. We found 12.8% of 610 coronary artery disease (CAD) patients of Central European background to be chronically infected with C. pneumoniae based on the repeated detection of chlamydial DNA in PBMC. Among those the -159C>T CD14 promoter polymorphism was more frequent (OR 1.7, 95% CI 1.08-2.65, P=0.0224) than among C. pneumoniae-negative subjects matched for age and gender. The Arg753Gln TLR2 and Asp299Gly TLR4 polymorphisms were not related to chlamydial infection. Susceptibility for chronic chlamydial infection of PBMC in CAD patients appears associated with the CD14-159C>T promoter polymorphism encoding for enhanced CD14 expression.