title: Role of human coronavirus NL63 in hospitalized children with croup.
abstract: BACKGROUND
  Human coronavirus NL63 (HCoV-NL63) has recently been implicated as a common cause of croup in children. This study was performed to evaluate viruses associated with croup in children, with an emphasis on HCoV-NL63.
  
  
  METHODS
  Nasopharyngeal aspirates were prospectively collected from 182 children hospitalized with croup at Seoul National University Bundang Hospital from January 2005 to June 2009. Multiplex reverse-transcriptase polymerase chain reaction was conducted for detection of 11 respiratory viruses, and medical records were reviewed.
  
  
  RESULTS
  Viruses were identified in 147 (80.8%) of the 182 croup patients. The 3 most commonly detected viruses were parainfluenza virus type 1 (PIV1) in 44 (24.2%) patients, HCoV-NL63 in 30 (16.5%) patients, and influenza A virus in 25 (13.7%) patients. Other detected viruses were rhinovirus in 22 (12.1%) patients, PIV type 3 and respiratory syncytial virus in 15 (8.2%) patients, human bocavirus in 8 (4.4%) patients, and several others in a few patients. Coinfections with > or = 2 viruses were found in 20 (11%) patients. HCoV-NL63 was identified primarily in winter, which coincides with the peak occurrence of croup. Patients with HCoV-NL63 infection were younger than those who were positive for PIV1 (median age 13 months versus 21 months, P = 0.006) and had shorter fever duration than influenza A virus infection (median 1.5 days versus 4 days, P = 0.000).
  
  
  CONCLUSIONS
  PIV1 and HCoV-NL63 were most commonly associated with patients who were hospitalized with croup. HCoV-NL63 is prevalent in winter and is associated with younger age and with shorter fever duration.
authors: Department of Pediatrics, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors: Ji Yeon
authors: JY
authors: Sung
authors: Hoan Jong
authors: HJ
authors: Lee
authors: Byung Wook
authors: BW
authors: Eun
authors: So Hee
authors: SH
authors: Kim
authors: So Yeon
authors: SY
authors: Lee
authors: Ju Young
authors: JY
authors: Lee
authors: Kyoung Un
authors: KU
authors: Park
authors: Eun Hwa
authors: EH
authors: Choi
mesh_terms: D000367:Age Factors; D002648:Child; D002673:Child, Hospitalized; D002675:Child, Preschool; D017934:Coronavirus / Q000145:classification* / Q000302:isolation & purification*; D018352:Coronavirus Infections / Q000453:epidemiology* / Q000473:pathology*; D003440:Croup / Q000453:epidemiology* / Q000209:etiology*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009305:Nasopharynx / Q000821:virology; D012367:RNA, Viral / Q000235:genetics; D012189:Retrospective Studies; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D012621:Seasons
chemical_list: D012367:RNA, Viral