Otolaryngological complications in patients infected with the influenza A (H1N1) virus

To describe bacterial upper respiratory infections in patients with influenza A (H1N1) virus during the 2009 pandemic.

Case series with chart review.

May 17 to July 17, 2009, Clinica Las Condes, Santiago, Chile.

Patients with clinical and/or laboratory diagnosis of influenza A (H1N1) who presented to the emergency department or other medical specialists with bacterial upper respiratory infection requiring antibiotic treatment within 2 months of influenza diagnosis.

A total of 10,048 cases of influenza A (H1N1) were identified by the emergency department. All patients received oseltamivir. Fifty-four patients (0.55%) who presented with bacterial upper respiratory infection within 2 months after the diagnosis of influenza were selected. The median time to presentation with bacterial respiratory infection was 12 days. Median age was 12 years, and 51.8% were male. The most common bacterial upper respiratory infections were acute rhinosinusitis (46.4%; median age, 17 years), acute otitis media (33.9%; median age, 5 years), and pharyngotonsillitis (14.3%; median age, 17 years). Four patients were hospitalized: 3 with streptococcal tonsillitis with prolonged fever and 1 with acute otitis media who later developed pansinusitis and otomastoiditis. There were no deaths in this group of patients.

There were few bacterial upper respiratory infections associated with influenza A (H1N1) (0.55%). The most common infections were acute otitis media in young children and acute rhinosinusitis and pharyngotonsillitis in young adults. These complications were more often seen during the 2 months following the influenza infection than at the time of diagnosis with influenza. Outcome was favorable for all patients.