LAUSR

Background Frequency of complications in children hospitalized due to Respiratory Syncytial Virus ( RSV) infectionsis high,and fever is supposed to correlatewith the risk of complications. The aim of the study was to assess the correlation between presence of fever, its magnitude,and durationand the risk of complications. Material and methods 221 children (10 days to 91 months; median 3 months) were hospitalized due to RSV infection (2016/2017 and 2017/2018 seasons).219 children met inclusion criteria (1patient discharged on parents’ request, and 1 with nosocomial infection were excluded). RSV infections were diagnosed with rapid antigen test and/or polymerase chain reaction. Acute otitis media(AOM) was diagnosed with otoscopy; pneumonia was confirmed with chest X-ray.We analyzed the highest fever, duration of fever, time of its presence (prior or during hospitalization). Results Fever was present in 40%(88/219) patients, including 69 cases of fever prior and 55 during hospitalization (36 cases prior and during hospitalization). The risk of complications was higher in patients with fever(OR=6.09, 95%CI: 3.3–11.2), and it was more clearly pronounced in patients with longer (at least 3 days) duration of fever (OR=9.04, 95%CI: 4.2–19.4) than in patients with higher (at least 39°C) fever (OR=2.2, 95%CI: 0.7–6.5). Presence of fever was related with higher risk of both pneumonia andAOM (OR=5.27, 95%CI: 2.7–10.4, and OR=3.43, 95%1.5–7.7 respectively). Longer fever duration correlated with pneumonia more significantly than higher fever (OR=6.34, 95%CI: 3.1–13.1 vs.OR=0.94, 95%CI: 0.4–2.5). Similar correlation was observed in AOM (4.53, 95%CI: 2–10.2 for longer vs.OR=1.96, 95%CI: 0.7–5.6 for higher fever). Presence of fever showed AUC=0.76 (95%CI: 0.69–0.83; p< 0.001) with cut-off value of 3 days showing 44% sensitivity and 91%specificity;78% and 70% positive and negative predictive value respectively. Conclusions Fever correlates with the risk of complications, but duration of fever seems to be crucial in terms of pneumonia and AOM.