A cluster of adenovirus serotype 3 infections in children in Northern Taiwan: Clinical features and laboratory findings

Background and Purpose: To define clinical manifestations and laboratory findings of adenovirus serotype 3 infections in children. Methods: A total of 499 children diagnosed with adenovirus infections based on throat virus cultures were treated in Chang Gung Children's Hospital from January 2004 to May 2005. Serotypes were determined in 197 strains, of which majority were serotype 3 (n = 147; 107 inpatients and 40 outpatients). Demographics, clinical presentations, and laboratory findings of the inpatients and demographics only of the outpatients were evaluated. Results: The mean age was 4 years and 7 months (range, 5 months to 12 years). Adenovirus serotype 3 infections were identified in 74.6% of the 197 children examined between January 2004 and May 2005. The mean time lag between specimen collection and a positive culture result was 8.3 days. The 3 most common symptoms were fever (100.0%), cough (87.9%), and rhinorrhea (73.8%). The mean duration of fever was 6 days, and the mean duration before admission was 4 days. The mean length of hospital stay was 5.4 days. The 3 most common diagnoses were tonsillitis/pharyngitis (43.0%), pneumonia/bronchopneumonia (32.7%), and acute otitis media (6.5%). Fifteen children had documented bacterial coinfection. Leukopenia (white blood cell [WBC] <5000/mm³) was noted in 2 patients (2.1 %) and leukocytosis (WBC ≥15,000/mm³) in 28 patients (30.4%). Of the 92 children with serum C-reactive protein level measurements, 74 children (80.4%) had a serum C-reactive protein level >40 mg/L Although 69 (64.0%) of the 107 hospitalized children never received antibiotic therapy, the outcomes were excellent. Conclusion: By recognizing that children with adenoviral infections may present with prolonged high fever, leuokocytosis, and elevated C-reactive protein levels, mimicking symptoms of bacterial infections, clinicians will be able to avoid the unnecessary prescription of antibiotics to these patients.