Role of human coronavirus NL63 in hospitalized children with croup.
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.
Sung
Ji Yeon
JY
Department of Pediatrics, Seoul National University College of Medicine, Seoul, Republic of Korea.
Lee
Hoan Jong
HJ
Eun
Byung Wook
BW
Kim
So Hee
SH
Lee
So Yeon
SY
Lee
Ju Young
JY
Park
Kyoung Un
KU
Choi
Eun Hwa
EH
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
D012367:RNA, Viral