[Chemoprophylaxis with palivizumab in Andalusia (Spain). Results of the 2000-2001 respiratory syncytial virus epidemic].

OBJECTIVE: To assess the hospitalization rate for bronchiolitis in newborns treated with palivizumab in Andalusia. PATIENTS AND METHODS: We performed a prospective study of 283 neonates and infants who received prophylaxis with palivizumab in Andalusia during the 2000-2001 bronchiolitis epidemic. We also performed a descriptive study of hospitalization for bronchiolitis, classifying patients according to gestational age and whether they had bronchopulmonary dysplasia (BPD). RESULTS: Most (86.9 %) of the treated patients were born before week 32 of gestation (63 % before week 30) and 38.4 % developed BPD. A total of 10.6 % of palivizumab-treated newborns were hospitalized for bronchiolitis, of which 3.9 % was caused by respiratory syncytial virus (RSV) (4.8 % of patients with BDP and 3.5 % of those without BPD were RSV-positive). Compared with preterm neonates born in weeks 31 or 32 of gestation, palivizumab-treated newborns born before week 31 showed a higher hospitalization rate for bronchiolitis (13.3 % vs 6.3 %; p < 0.05) and that for RSV was three times higher (5.0 % vs 1.6 %; p < 0.05). Age at admission was 5.8 3.2 months. Length of hospital stay was shorter in RSV-positive patients with bronchiolitis (6.7 vs 7.6 days; p > 0.10). Admission to the intensive care unit was required in 0.7 % of patients and in 50 % of those who were RSV-positive. Adverse effects were observed in 5.1 % of palivizumab-treated patients. CONCLUSION: The marked differences in the perinatal antecedents of patients receiving immunoprophylaxis may explain the variations in the efficacy of palivizumab reported in available studies.