title: Clinical characteristics of Korean pediatric patients critically ill with influenza A (H1N1) virus.
abstract: BACKGROUND
  Novel influenza A (H1N1) virus infection has persisted mainly through person-to-person transmission in schools. However, data on critically ill patients infected with H1N1 are currently limited. This study was conducted to investigate the epidemiological characteristics, clinical features, treatment modalities, and clinical outcomes of pediatric patients critically ill with H1N1 infection.
  
  
  METHODS
  Subjects included 30 critically ill pediatric patients reported to the Korea Centers for Disease Control and Prevention (KCDC) between June and November 2009. Data were obtained by medical record review and interviews with primary treating physician.
  
  
  RESULTS
  Of the 30 patients, 14 died and 16 were discharged from the hospital with complete recovery. The median patient age was 7 years (range, 2 months to 18 years). Nineteen patients belonged to the high-risk group. Cough was the most common initial symptom, followed by fever. In most patients, serum levels of C-reactive protein and lactate dehydrogenase were elevated. Oseltamivir, an antiviral agent, was administered to 29 patients. The most common causes of death were encephalopathy and myocarditis, with a higher mortality rate in the high-risk group. Platelet counts were significantly lower than normal and serum aspartate aminotransferase levels significantly higher in the non-survivors.
  
  
  CONCLUSIONS
  The results of this study suggest that Korean high-risk pediatric patients have an elevated mortality rate following infection with novel influenza A (H1N1) virus. Further studies involving high-risk pediatric patients classified using consistent criteria are needed to confirm our results.
authors.affiliation: Korea Centers for Disease Control and Prevention (KCDC), Division of Epidemic Intelligence Service, Seoul, Korea.
authors.forename: Soo Youn
authors.initials: SY
authors.lastname: Shin
authors.forename: Joon Hyung
authors.initials: JH
authors.lastname: Kim
authors.forename: Hyun Su
authors.initials: HS
authors.lastname: Kim
authors.forename: Young A
authors.initials: YA
authors.lastname: Kang
authors.forename: Ha Gyung
authors.initials: HG
authors.lastname: Lee
authors.forename: Jin Seok
authors.initials: JS
authors.lastname: Kim
authors.forename: Jong-Koo
authors.initials: JK
authors.lastname: Lee
authors.forename: Woo Kyung
authors.initials: WK
authors.lastname: Kim
mesh_terms: D005260:Female; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype; D007251:Influenza, Human / Q000401:mortality* / Q000628:therapy*; D008297:Male; D056910:Republic of Korea / Q000453:epidemiology; D012720:Severity of Illness Index