718. Viral Coinfection and Nasal Cytokines in Children with Acute Bacterial Sinusitis (ABS)

BACKGROUND: ABS is one of the most common infections in childhood leading to antibiotic prescriptions, but remains a clinical diagnosis. Laboratory testing does not aid diagnosis and there are no predictors to identify those who will respond to therapy or develop complications. Thus, the tools to diagnose and manage ABS remain limited. Initial viral infection predisposes to development of ABS. However, there is poor understanding of the contribution of viral infection to pathogenesis, rate of complications, or the immune response to ABS. The objective of this study was to define bacterial upper airway colonization, viral co-infection and cytokine response in the upper airway during ABS. METHODS: In the context of an ongoing larger prospective clinical study, children were enrolled who were diagnosed with ABS using standardized clinical criteria. Nasopharyngeal (NP) samples were processed for bacterial culture for S. pneumoniae, H. influenzae, S. pyogenes and M. catarrhalis; real-time PCR viral testing and cytokine measurement by qPCR. We correlated these findings with clinical symptoms at the time of presentation. RESULTS: Of 184 enrolled children (median age 4.9 years), 134 (72.8%) had a positive bacterial culture for potentially pathogenic bacteria and 50 (27.2%) had growth of normal flora. A total of 129 (70.4%) subjects tested positive for a virus. The most common virus detected was rhinovirus (n = 86) followed by influenza virus (n = 23) and adenovirus (n = 21). A total of 102 patients (70.4%) had both a positive pathogenic bacterial culture and viral detection. Patients who had a bacterial pathogen plus a viral detection had a significantly higher expression of IL-6, IL-8 and IL-25 (P < 0.001). Univariable analysis found no correlation between clinical presentation with viral and/or cytokine expressions. CONCLUSION: Children meeting clinical criteria for ABS and a NP swab with a pathogenic bacteria plus viral detection demonstrated higher expression of inflammatory cytokines compared with subjects whose culture had normal respiratory flora. DISCLOSURES: J. V. Williams, Quidel: Board Member, Consulting fee. GlaxoSmithKline: Consultant, Consulting fee.