title: Characteristic findings of pediatric inpatients with pandemic (H1N1) 2009 virus infection among severe and nonsevere illnesses.
abstract: We analyzed the clinical features of inpatients at a Japanese pediatric department who were infected with pandemic (H1N1) 2009 virus. Study participants included 46 children hospitalized from July 2009 to January 2010. Infection with the virus was confirmed using real-time reverse transcriptase polymerase chain reaction (RT-PCR). The epidemic month was October 2009; 34 patients were boys, and median age was 7 years. Pandemic influenza-associated respiratory diseases included pneumonia (n = 42), bronchitis (n = 3), and pharyngitis (n = 1). The median time from onset to admission was 3 days. Children were divided into those with severe (n = 32) versus nonsevere illnesses (n = 14) according to Japanese guidelines. Significant features in the severe group were younger age, previous asthmatic attack, exacerbation of asthma, decreased oxygen saturation, elevated white blood cell/neutrophil counts and serum lactate dehydrogenase, and longer times from admission to being afebrile and discharged. Both groups showed lymphopenia at admission. Additional infection with Streptococcus pneumoniae was frequent in the severe group. Whereas 44 patients received antiviral therapy (median times from onset to initiation 2 days), 32 received antibiotics (median duration 7 days). All children recovered, with a median hospital stay of 8 days. Our observations suggest that history of asthma and preschool age might be risk factors for severe illness. Prompt initiation of antiviral and antibiotic treatments should be considered to prevent development of severe illness.
authors.affiliation: Department of Pediatrics, National Hospital Organization Tokyo Medical Center, 2-5-1 Higashigaoka, Meguro-ku, Tokyo, 152-8902, Japan.
authors.forename: Takafumi
authors.initials: T
authors.lastname: Okada
authors.forename: Miyuki
authors.initials: M
authors.lastname: Morozumi
authors.forename: Keita
authors.initials: K
authors.lastname: Matsubara
authors.forename: Osamu
authors.initials: O
authors.lastname: Komiyama
authors.forename: Kimiko
authors.initials: K
authors.lastname: Ubukata
authors.forename: Takashi
authors.initials: T
authors.lastname: Takahashi
authors.forename: Satoshi
authors.initials: S
authors.lastname: Iwata
mesh_terms: D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D000998:Antiviral Agents / Q000627:therapeutic use; D001991:Bronchitis / Q000150:complications / Q000188:drug therapy / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D007223:Infant; D053118:Influenza A Virus, H1N1 Subtype / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*; D007251:Influenza, Human / Q000150:complications* / Q000188:drug therapy / Q000453:epidemiology* / Q000821:virology; D007564:Japan / Q000453:epidemiology; D008297:Male; D058873:Pandemics; D010372:Pediatrics; D010612:Pharyngitis / Q000150:complications / Q000188:drug therapy / Q000453:epidemiology; D011014:Pneumonia / Q000150:complications / Q000188:drug therapy / Q000453:epidemiology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012720:Severity of Illness Index
chemical_list: D000900:Anti-Bacterial Agents; D000998:Antiviral Agents