Lower respiratory tract illness and RSV prophylaxis in very premature infants

Aims: To determine the frequency of and the risk factors for readmissions for any lower respiratory tract illness (LRTI) and for respiratory syncytial virus (RSV) documented LRTI in children born very prematurely who had or had not received RSV prophylaxis. Methods: Multicentre prospective longitudinal cohort study of 2813 infants, born between April 2000 and December 2000 at less than 33 weeks of gestational age, and followed until the end of the epidemic season. Results: Among the 2256 children who had no bronchopulmonary dysplasia at 36 weeks of postmenstrual age and were not submitted to RSV prophylaxis, 27.4% were readmitted at least once for any reason during the epidemic season; 15.1% and 7.2% were readmitted at least once for any LRTI and RSV related LRTI, respectively. Children born at less than 31 weeks' gestation, having an intrauterine growth restriction, or living in a single mother family were at a significantly higher risk of readmission for LRTI in general as well as for RSV related LRTI. Of the 376 children submitted to prophylaxis, 28.2% were readmitted at least once for any LRTI and 6.1% for RSV related LRTI. Conclusion: One out of four children who had received no prophylaxis, was born very prematurely, and was without bronchopulmonary dysplasia at 36 weeks of postmenstrual age, was readmitted at least once for any reason. Roughly 50% and 20% of these readmissions were related to a LRTI and an RSV infection, respectively. Further epidemiological studies are warranted to assess the aetiology and impact of other respiratory pathogens on post-discharge readmission and respiratory morbidity in this population.