Molecular characteristics of Staphylococcus aureus isolated from neonates
10.3760/cma.j.issn.1673-4912.2019.11.003
- VernacularTitle: 新生儿金黄色葡萄球菌感染致病株分子特征研究
- Author:
Chen SUN
1
;
Yajuan WANG
2
;
Xin YANG
1
;
Lijuan WANG
1
;
Yujie QI
2
;
Fang DONG
3
;
Wenqi SONG
3
;
Yingchao LIU
1
;
Kaihu YAO
4
;
Suyun QIAN
1
Author Information
1. Pediatric Intensive Care Unit, Beijing Children′s Hospital, Capital Medical University, National Center for Children′s Health, Beijing 100045, China
2. Department of Neonatal Unit, Beijing Children′s Hospital, Capital Medical University, National Center for Children′s Health, Beijing 100045, China
3. Bacteriology Laboratory, Beijing Children′s Hospital, Capital Medical University, National Center for Children′s Health, Beijing 100045, China
4. MOE Key Laboratory of Major Diseases in Children, National Key Discipline of Pediatrics (Capital Medical University), National Clinical Research Center for Respiratory Diseases, Beijing Key Laboratory of Pediatric Respiratory Infection Diseases, Beijing Pediatric Research Institute, Beijing Children′s Hospital, Capital Medical University, National Center for Children′s Health, Beijing 100045, China
- Publication Type:Journal Article
- Keywords:
Staphylococcus aureus;
Neonate;
Molecular characteristics;
Virulence;
Antibiotic resistance
- From:
Chinese Pediatric Emergency Medicine
2019;26(11):813-819
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To study the clinical and molecular characteristics of Staphylococcus aureus(S.aureus ) isolated from neonates of Beijng Children′s Hospital.
Methods:The clinical information of S. aureus infection in newborns of Beijing Children′s Hospital from February 2016 to January 2017 was collected.The molecular biological characteristics of S. aureus isolates were detected.Methicillin-resistant S. aureus (MRSA) and methicillin-susceptible S. aureus(MSSA)were identified, using the cefoxitin disc method and the detection of the mecA gene.Multilocus sequence typing(MLST)and spa typing were analyzed using the PCR, and the staphylococcal chromosomal cassette mec(SCCmec) type was analyzed for the MRSA isolates.Eleven adhesion gene and three virulence genes(pvl, psma, hlα )were also detected by PCR.Antimicrobial susceptibility testing was performed by agra dilution method or E-test method.
Results:The total of 57 cases of neonatal S. aureus infection were collected during the study.The most common clinical diagnosis was 38 cases (66.7%) of pneumonia and 28 cases (49.1%) of skin infection syndrome (SSTI). There were 31 cases (54.4%) with MRSA infection and 26 cases (45.6%) with MSSA infection.The proportion of SSTI in the MRSA group (64.5%) and the infection of more than 2 sites (61.3%, 19/31) were significantly higher than those in the MSSA group (30.8%, 8/26 and 23.1%, 6/31). There were 16 MLST types and 29 spa types, the most common ones were ST59 (40.4%) and t437 (33.33%), respectively.The most common popular clones of MRSA and MSSA were ST59-SCCmecIVa-t437 (54.8%) and ST22-t309, respectively(11.5%). The sdrE carrying rate of MRSA was higher than that of MSSA, while the sdrD and cna carrying rates were lower than those of MSSA (P<0.05). The other adhesion and virulence gene carrying rates were not significantly different between the two strains.The multi-drug resistance rate of all strains was 61.4%(35/57). Except for lactam antibiotics, the most common resistant phenotypes of MRSA and MSSA were ERY-CLI, accounting for 74.2% and 26.9%, respectively.
Conclusion:The main types of neonatal S. aureus infection in our hospital were pneumonia and SSTI.SSTI and multi-site infections of MRSA infection are more common.MRSA and MSSA isolates have clonal dissemination characteristics.The most common clones are ST59-SCCmecIVa-t43 and ST22-t309, which show no significant differences in the status of carrying virulence factors between them.The multi-drug resistance rate of neonatal S. aureus isolates is higher.
