[Epidemiological study on nasal carriage in hospitalized children infected with Staphylococcus aureus].
OBJECTIVE
To study the relationship between nasal carriage and Staphylococcus aureus (S. aureus) infection in hospitalized children.


METHODS
Fifty-six hospitalized children infected with S. aureus were recruited in this study. Nasal swabs were collected and cultured, and the nasal carriage rate of S. aureus was examined. PVL virulence gene and mecA resistance gene were both detected in clinical strains and nasal carriage strains by PCR.


RESULTS
Twenty-two (39%) of the 56 children had nasal carriage of S. aureus, and most of them (18 cases) were younger than one year. Among these 22 children, 11 (50%) had previous hospitalization over the past year. In the infected strains, the rate of methicillin-resistant S. aureus (MRSA) was 29% (16/56), while it was 32% (7/22) in carriage strains. The mecA positive results in clinical strains were consistent with the results in nasal carriage strains. Among 5 PVL-positive nasal carriage strains, 4 (90%) could be matched with their clinical strains, all of which were MRSA.


CONCLUSIONS
Nasal carriage is a potential risk factor for S. aureus infection. Nosocomial transmission may lead to nasal carriage, which can cause S. aureus infection. The isolation rate of MRSA is high in hospitalized children infected with S. aureus, which implies that more attention is needed for this situation. The isolates from noses may be clonally identical to the isolates from clinical secretions, and the homology between them needs to be confirmed by multi-locus sequence typing.
Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu 610041, China. suemin2005@163.com.
Shan
S
Tan
Chao-Min
CM
Wan
Jian-Jun
JJ
Deng
Guo-Guang
GG
Xiao
Qiong
Q
Liao
Min
M
Shu
D001426:Bacterial Proteins / Q000235:genetics; D002353:Carrier State / Q000382:microbiology*; D002648:Child; D002673:Child, Hospitalized; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus / Q000302:isolation & purification; D009666:Nose / Q000382:microbiology*; D046915:Penicillin-Binding Proteins; D013203:Staphylococcal Infections / Q000382:microbiology*; D013211:Staphylococcus aureus / Q000302:isolation & purification*
D001426:Bacterial Proteins; D046915:Penicillin-Binding Proteins; C487789:mecA protein, Staphylococcus aureus