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World Health Organization (WHO) reported that a total of 559 meningitis cases and 18 deaths were reported in the southeast of Niger from November 1, 2022 to January 27, 2023.Children were the major of patients.Among the laboratory confirmed cases, 93.7%(104/111) were epidemic cerebrospinal meningitis.Since 2021, the epidemic of meningococcal disease has attacked the gay and bisexual men in Florida, USA.This paper briefly reviews the occurrence and development of the two outbreaks of epidemic cerebrospinal meningitis, as well as the causes and countermeasures.The current prevention and control measures of meningitis is discussed based on the " Defeating meningitis by 2030: Global Road Map" issued by WHO in 2021.This paper is expected to attract the attention and to improve awareness and vigilance of domestic clinical and public health workers, which would lead to strengthen the surveillance, prevention and control of meningitis.
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Superantigens are highly mitogenic exotoxins produced by bacteria and viruses.They can bind to the major histocompatibility complex class Ⅱ, stimulate T cell receptor molecules to release a large quantity of proinflammatory cytokines, and activate the immune system in vastly low concentrations.Superantigens have been the most effective T cell mitogen discovered so far.Superantigens play important roles in infection diseases caused by streptococcal pathogens, and they can facilitate pathogen colonization, proliferation, and dissemination.Further research of biological chara-cteristics of streptococcus superantigens is vital to understanding the streptococcus pathogenesis, prevention and treatment of streptococcus infection.In this article, advances in the classification, biological properties, pathogenesis, deve-lopment and application of streptococcal superantigens were reviewed, so as to improve the clinical understanding and provide reference for in-depth research of related diseases.
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Objective:To analyze the genetic characteristics of Group A Streptococcus (GAS) isolated from the pharynx of children with scarlet fever-like erythema. Methods:Pharyngeal GAS isolates were collected retrospectively from children with scarlet fever-like erythema admitted in the Department of Dermatology, Beijing Children′s Hospital, Capital Medical University from June 2019 to February 2020.PCR and sequencing were used to detect emm genotyping and superantigen genes( speA, speB, speC, speF, speG, speH, speI, speJ, speK, speL, speM, ssa and smeZ) of the isolates.Data were compared by the chi-square test or Fisher′ s exact test between groups. Results:A total of 147 GAS strains were collected.The main emm genotypes were emm1.0 in 76 strains (51.70%) and emm12.0 in 60 strains (40.82%). Other 7 emm genotypes were all found in less than 5 strains.The detection rate of speF, smeZ, speG, speC, speB and ssa were as high as 100.00%(147/147 strains), 100.00%(147/147 strains), 99.32%(146/147 strains), 95.24%(140/147 strains), 94.56%(139/147 strains) and 92.52%(136/147 strains), respectively. speA, speJ, speI, speH and speM had a low detection rate of 51.70%(76/147 strains), 49.66%(73/147 strains), 32.65%(48/147 strains), 23.81%(35/147 strains) and 4.08%(6/147 strains), respectively.No speK and speL were detected.The frequencies of speA and speJ in emm1.0 strains (65/76 strains, 85.53% and 64/76 strains, 84.21%) were significantly higher than those in emm12.0 strains (4/60 strains, 6.67% and 6/60 strains, 10.00%). However, the frequencies of speH and speI in emm1.0 strains (7/76 strains, 9.21% and 2/76 strains, 2.63%) were significantly lower than those in emm12.0 strains (28/60 strains, 46.67% and 45/60 strains, 75.00%) (all P<0.001). Conclusions:At present, emm1.0 and emm12.0 are the main GAS strains isolated from the throat of children with scarlet fever-like erythema in Beijing, and emm1.0 is more common.There is a correlation between emm genotyping and the superantigen gene profile.Type 1 superantigen gene profile is significantly more frequently detected in emm1.0 strains than in emm12.0 strains.Type 2, 3 and 4 superantigen gene profiles are significantly more frequently detected in emm12.0 strains than in emm1.0 strains.
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Group A Streptococcus (GAS) is a very important pathogen, especially for children.On a global scale, GAS is an important cause of morbidity and mortality.But the burden of disease caused by GAS is still unknown in China and also has not obtained enough attention.For this purpose, the expert consensus is comprehensively described in diagnosis, treatment and prevention of GAS diseases in children, covering related aspects of pneumology, infectiology, immunology, microbiology, cardiology, nephrology, critical care medicine and preventive medicine.Accordingly, the consensus document was intended to improve management strategies of GAS disease in Chinese children.
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Objective:To evaluate the antibacterial activity of pediatric Faropenem sodium against common pathogens isolated from children′s respiratory tract in vitro, and to provide reference for its clinical research and application. Methods:Retrospective analysis.The minimum inhibitory concentration (MIC) of Faropenem sodium, Merope-nem, Imipenem and other antibiotics was determined by the agar dilution method.A total of 156 strains of Streptococcus pneumoniae [including 32 strains of Penicillin-susceptible Streptococcus pneumoniae (PSSP), 28 strains of Penicillin-intermediate Streptococcus pneumoniae (PISP) and 96 strains of Penicillin-resistant Streptococcus pneumoniae (PRSP)], 98 strains of Haemophilus influenza, 173 strains of Klebsiella pneumoniae, and 55 strains of Moraxella catarrhali clinical isolates were used.MIC 50, MIC 90 and the accumulative inhibition of the bacteria were investigated. Results:The MIC of Faropenem sodium against all the Streptococcus pneumoniae strains ranged from 0.010-2.000 mg/L.There was no difference in the MIC distribution of Faropenem sodium against PSSP, PISP and PRSP, and the MIC 90 value was all 1.000 mg/L.Faropenem sodium inhibited all the Haemophilus influenza strains at concentrations ranging from 0.030-8.000 mg/L.There was no difference in the MIC distribution of Faropenem sodium against Haemophilus influenza with or without β-lactamase and Ampicillin resistance.The MIC 90 value was all 4.000 mg/L.Ho-wever, the MIC of Faropenem sodium against Klebsiella pneumoniae ranged from 0.250 to above 32.000 mg/L, and both MIC 50 and MIC 90 were greater than 32.000 mg/L.Faropenem sodium inhibited all the Moraxella catarrhalis strains at concentrations ranging from 0.030-2.000 mg/L, with MIC 50 being 0.500 mg/L and MIC 90 being 1.000 mg/L. Conclusions:Antimicrobial susceptibility testing results in vitro demonstrate that pediatric Faropenem sodium has satisfactory antibacterial activities against Streptococcus pneumoniae, Haemophilus influenza, and Moraxella catarrhalis, but comparatively weak antibacterial activities against Klebsiella pneumoniae.
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Objective:To examine whether the mixed infection rate in pertussis infants is significantly higher than that in non-pertussis infants with respiratory tract infection, to explore the mixed infection pathogen distribution in pertussis infants, and to provide reference for clinical diagnosis and treatment.Methods:A case-control study was conducted on 118 nasopharyngeal swabs collected from infants who applied for clinical pertussis etiological testing (culture and specific nucleic acid detection of Bordetella pertussis) in Beijing Children′s Hospital, Jiaxing Maternity and Child Health Care Hospital and Wuhu No.1 People′s Hospital from August 2018 to January 2021.According to the pertussis etiological testing results, the patients were divided into the pertussis group (65 cases) and non-pertussis group (53 cases). Thirty-three pairs of cases were matched according to age, onset season and city.All nasopharyngeal swabs were tested for infections of other pathogens using FilmArray RP2, which can detect 21 respiratory infection pathogens.The mixed infection rate was compared between groups by Chi- square test. Results:According to the FilmArray RP2 test results, 56.9%(37/65) cases in pertussis group and 15.1%(8/53) cases in the non-pertussis group were positive for multiple pathogens, and the difference was statistically significant ( χ2=21.651, P<0.001). The top 5 mixed infection pathogens in pertussis infants were human rhinovirus/enterovirus (HRV/EV) (38.5%, 25/65), parainfluenza virus (PIV) (18.5%, 12/65), respiratory syncytial virus (RSV) (10.8%, 7/65), coronavirus (Cov) (10.8%, 7/65), and adenovirus (ADV) (7.7%, 5/65). The mixed infection rates of the pertussis group in spring, summer, autumn and winter were 46.2% (6/13), 58.3%(14/24), 55.6%(5/9), and 63.2%(12/19), respectively.Comparison of matched and unmatched cases achieved similar results. Conclusions:Among clinical suspected pertussis infant specimens, the mixed infection rate in confirmed cases is tremendously higher than that in non-pertussis infants.The main mixed infection pathogens in pertussis infants are HRV/EV, PIV, RSV, Cov, and ADV.Mixed infection in pertussis children commonly occurs in four seasons, with the highest incidence in winter.
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Objective:To evaluate the relationship between the Panton-Valentine leukocidin (pvl) strain and clinical characteristics, and to describe the molecular biological characteristics of invasive Staphylococcus aureus ( S. aureus) infected clinical isolates. Methods:The isolates of S. aureus caused by invasive infection were collected in Beijing Children's Hospital Affiliated to Capital Medical University from January 2016 to December 2019, and the clinical data of the corresponding children were collected retrospectively using electronic medical records. Multilocus sequence typing, spa typing and pvl gene were analyzed using the PCR. In addition, the minimum inhibitory concentrations (MIC) of antibiotics of all isolates were detected by the micro-broth dilution method, and the isolates were divided into the pvl+ and pvl- groups according to whether or not the S. aureus isolates carried pvl. The t test and the Mann-Whitney U test were used to compare the clinical symptoms between the pvl+ and pvl- groups. Chi-square test was used to compare the drug susceptibility between the two isolates. Results:A total of 127 cases of invasive S. aureus infection were collected during the study period. The white blood cell count, neutrophil count, and C-reaction protein level in the pvl+ group were significantly higher than those in the pvl- group ( P=0.001, P=0.001, P=0.005). The rate of pvl carrier was 44.9%. Among 57 pvl+ pathogenic strains, 64.9% (37/57) were MRSA. The multidrug resistance rate of pvl- isolates was higher than that of pvl+ isolates (70% vs. 49.12%, P=0.02). Conclusions:In invasive S. aureus infection, pvl+ strain is associated with elevated inflammatory markers in children. the positive rate of pvl is higher in clinical isolates, and the multidrug resistance rate of pvl- S. aureus is higher.
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Pertussis toxin(PTx), an important toxin that produced by Bordetella pertussis, is an important pathogenic factor in the pathogenesis of whooping cough.The previous studies have showed that PTx interacting proteins vary distinctly in size, ranging from the 43 kD surface protein of human lymphocyte to the 200 kD surface protein of insulin secreting cells.PTx has been shown to interact with N-linked oligosaccharides on the surface of host cells, sialoglycoprotein-like factors, glycoproteins such as haptoglobin, fetuin, G D1a glycolipids.Especially, the interaction of PTx with its receptor Gi protein can result in increased intracellular cAMP level, which will lead to multiple physiological responses.However, the current limited understanding of other PTx modified substrates and interacting proteins in cells has seriously hindered our understanding on the mechanism that PTx regulates other signaling pathways and physiological functions of the host.
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Objective:To determine whether these Streptococcus pneumoniae isolates identified by routine cli-nical methods that cannot be serotyped by the quellung reaction contain other species of viridans group streptococci and to determine the antibiotic susceptibility to provide reference for clinical medicine. Methods:A total of 105 isolates identified as Streptococcus pneumoniae by routine methods with negative quellung reaction results were enrolled in this study.Multilocus sequence analysis (MLSA) and matrix-assisted laser desorption/ionization time of flight mass spectrometry(MALDI-TOF-MS) were used to identify species of these isolates.Broth microdilution method was used to detect susceptibilities of 14 antibiotics. Results:Twenty-four of the 105 isolates were identified as Streptococcus pseudopneumoniae by MLSA, and the remaining 81 were Streptococcus pneumoniae.Six isolates of Streptococcus pseudopneumoniae were misidentified as Streptococcus pneumoniae, and 3 isolates as Streptococcus mitis/ oralis by MALDI-TOF-MS; and 6 isolates of Streptococcus pneumoniae were misidentified as Streptococcus pseudopneumoniae.All isolates were susceptible to Vancomycin, Levofloxacin and Moxifloxacin.The non-susceptibility rates between Streptococcus Pneumoniae and Streptococcus pseudopneumoniae against Ceftriaxone(28.4% vs.58.4%), Chloramphenicol(39.5% vs.4.2%), Erythromycin(77.8% vs.95.8%) and Azithromycin(75.3% vs.95.8%) were obviously different. Conclusions:Routine clinical methods may misidentify some Streptococcus pseudopneumoniae as Streptococcus pneumoniae, and so does the MALDI-TOF-MS.In addition, Streptococcus pneumoniae isolates with negative results of the quellung reaction showed differences in antimicrobial resistance.And misidentification may affect the evaluation of pathogenic bacteria and antibiotic resistance.
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Objective:To investigate the serotype distribution and drug resistance of Streptococcus pneumoniae ( S. pneumoniae) isolated in Urumqi Children′s Hospital and to evaluate the significances of 13-valent pneumococcal conjugate vaccine (PCV13) in preventing infection and controlling drug resistance. Methods:The S. pneumoniae isolates stored in clinical laboratory of Urumqi Children′s Hospital from January to December in 2018 were re-cultured.The serotypes were detected by capsule swelling experiment to assess the coverage rate of PCV13.The minimum inhibitory concentration (MIC) of Penicillin, Amoxicillin, Cefotaxime and Ceftriaxone were detected by E-test method, and the susceptibility of the isolates to Meropenem and other 9 antibiotics was detected by VITEC 2 Compact system. Results:A total of 225 S. pneumoniae strains were identified.The common serotypes were 19F (32.9%), 23F (12.0%), 19A (10.7%), 6B (10.2%) and 6A (8.0%). PCV13 coverage rate was 80.4%.There was no significant difference in serotype distribution and PCV13 coverage between children < 2 years old and ≥ 2 years old, as well as between Han and minority people.The 57.8% and 31.7% strains showed intermediate susceptibility and resistance against oral Penicillin, respectively.Based on the breakpoints for meningitis, 89.4% strains were resistant against pare-nteral Penicillin, and 47.5% and 64.6% strains were non-susceptible (mainly intermediately susceptible) to Ceftria-xone and Cefotaxime, respectively.The resistance rates of strains against Erythromycin, Sulfamethoxazole-trimethoprim and Tetracycline were as high as 98.1%, 67.6% and 89.6%, respectively.More than 90% tested isolates were susceptible to Amoxicillin, Meropenem, Levofloxacin or Moxifloxacin.PCV13 strains were more resistant to Penicillin than non-PCV13 strains. Conclusions:The serotypes 19F, 23F, 19A, 6B and 6A are common among the S. pneumoniae isolated in Urumqi.The coverage rate of PCV13 is about 80%.There was no significant difference in serotype distribution between Han and minority nationality children. S. pneumoniae were frequently resistant against Erythromycin.The high resistance to Penicillin and other beta-lactams should be taken into account when treatment is decided for suspected pneumococcal meningitis.Universal administration of PCV13 would be effective strategy to prevent pneumococcal infection in children and to control the drug resistance of S. pneumoniae.
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Objective:To investigate the isolation characteristics and the antibiotic resistance of Streptococcus pneumoniae in hospitalized children from the Bao′an District of Shenzhen for many consecutive years, and to provide evidence for the assessment as well as clinical prevention and treatment of Streptococcus pneumoniae infection. Methods:The isolation rate and sample source of Streptococcus pneumoniae isolates as well as age composition of hospitalized children in Bao′an Maternal and Child Health Hospital of Shenzhen city from January 2012 to December 2018 were retrospectively analyzed.The susceptibility of the isolates to antibiotics was tested by disk diffusion method and E-test method. Results:(1) From 2012 to 2018, a total of 90 807 specimens were retrospectively summarized, 9 193 strains of Streptococcus pneumoniae were isolated, with an isolation rate of 10.1%, which was the first pathogen; 98.68% (9 072/9 193 cases) from respiratory tract samples and 97.20% from sputum samples.Among 107 strains isolated from aseptic body fluid specimens, 97 strains were blood specimens. Streptococcus pneumoniae was the most common bacteria with positive culture in aseptic body fluids.(2) The isolation rate of Streptococcus pneumoniae was 10.7% in children under 2 years old, 10.2% in children between 2 and 5 years old and 4.1% in children over 5 years old.About 97% of Streptococcus pneumoniae isolates came from children under 5 years old.(3) According to breakpoints of non-meningitis strains, the sensitivity rate of parenteral Penicillin was 93.18%, the mediation rate was 6.79%, the resistance rate was only 0.03%, the lowest drug concentration to inhibit the growth of 50% bacteria(MIC 50) value was 0.50 and the lowest drug concentration to inhibit the growth of 90% bacteria(MIC 90) value was 2.00; the sensitivity rate of Ceftria-xone was 76.55%, the mediation rate was 20.18%, the resistance rate was 3.26%, the MIC 50 value was 1.00 and the MIC 90 value was 2.00; when interpreted by the breakpoint of meningitis strains, the resistance rate of extra-gastrointestinal Penicillin reached 77.22%, and the mediation rate of Ceftriaxone increased to 30.48% and the drug resistance rate reached 18.45%.The drug resistance rates of Erythromycin, Clindamycin, Tetracycline and Compound neomycin were all over 85.00%.The resistance rates against Levofloxacin and Chloramphenicol were 0.16% and 7.85% respectively.No Vancomycin-resistant Streptococcus pneumoniae was found. Conclusions:Streptococcus pneumoniae is the first bacterial pathogen causing respiratory tract and invasive infection in hospitalized children under 5 years old in this area.Penicillin is still the preferred drug for non-meningitis pneumococcal infection, but the drug resistance rate is high in meningitis patients.
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Streptococcus pneumoniae is the dominant pathogen of respiratory tract infections in children.Due to the long-term overuse of antibiotics, the growing resistance of Streptococcus pneumoniae against many kinds of antimicrobial agents, including the β-lactamides, the macrolides, the fluoroquinolones and so on, increasing infections caused by drug-resistant pneumococcal isolates, as well as the wide prevalence of such infections have posed great challenges to the selection of antibiotics in clinical practice.In this article, changes of resistance patterns of Streptococcus pneumoniae isolates against commonly used antimicrobial agents in Chinese children in the past 30 years were reviewed.The rapid development of antibiotic resistance of Streptococcus pneumoniae necessitates the prevention and control of Streptococcus pneumoniae infections as well as the reduction of unreasonable use of antibiotics.
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Objective:To explore the clinical characteristics, drug resistance and the serotype distribution of the isolates from peadiatric patients with pneumococcal meningitis (PM).Methods:Clinical data, follow-up outcomes, drug susceptibility of isolated strains and serotyping results of 72 children diagnosed as PM and hospitalized in Beijing Children′s Hospital, Capital Medical University, from January 2012 to December 2017 were retrospectively analyzed, and the independent risk factors of mortality in the PM patients were analyzed.Results:There were 46 males and 26 females.In 72 PM cases, with the age ranging from 1 month to 9 years, and hospital stay from 1 to 363 days(median, 22.0 d). A total of 71 cases (98.6%) had community-acquired infections.There were 28 cases (38.9%) with definite underlying diseases, the top 3 of which were cerebrospinal fluid rhinorrhea(6 cases), head trauma (4 cases)and immunodeficiency diseases (4 cases). Fever (72 cases, 100.0%) was the most common clinical symptom, followed by depression of spirit, change of consciousness (46 cases, 63.9%), vomitting (45 cases, 62.5%), convulsion (42 cases, 58.3%), increased tension of anterior fontanelle (27 cases, 37.5%) and headache (17 cases, 23.6%) .There were 44 cases (61.1%) of neurological complications, including 29 cases (40.3%) of subdural effusion.Bacterial meningitis recurred in 2 cases, both of which were recurrent Streptococcus pneumoniae infection.The intracranial infections were divided into meningitis (43.1%, 31/72 cases) and meningoencephalitis (56.9%, 41/72 cases) .The penicillin nonsensitive rate of meningitis isolates was 74.3%, and their resistance rate to Erythromycin, Clindamycin and Tetracycline were 95.7%, 95.7% and 89.1%, respectively.All meningitis isolates were susceptible to Levofloxacin, Vancomycin and Linezolid.The serotypes of 24 cases (33.3%) were identified, among which 8 strains were type 19F (33.4%), 5 strains were type 14, 4 strains were type 23F, 3 strains were type 6A, 2 strains were type 19A, 1 strain was type 1 and 1 strain was type 15B, with a 13-valent protein-polysaccharide conjugate vaccine (PCV13) coverage rate of 95.8%(23/24 strains). Among all children that were followed up, 51 cases got better, 21 cases (case fatality rate was 29.2%) were confirmed dead, and 21 children (29.2%) had sequelae.The multiva-riate Logistic regression analysis suggested that respiratory failure and peripheral blood white blood cell count <4×10 9/L were independent risk factors for death of children with PM(all P<0.05). Conclusions:Most PM cases in this center are children under 5 years old.Cerebrospinal fluid rhinorrhea, head trauma and immunodeficiency diseases are common underlying diseases in children with PM.Respiratory failure or peripheral blood leukopenia during the course of the disease may indicate a poor prognosis.
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Pneumococcal diseases are one of the serious global public health problems, which seriously threa-tens the health and brings heavy economic burden to children and adults in the world.Pneumococcal conjugated vaccines (PCVs) have been proved to be a safe and effective intervention to prevent invasive and non-invasive pneumococcal diseases.PCVs are conducive to saving lives, preventing disability and lowering costs in the world, especially in Africa and Asia.
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Objective:To investigate the molecular characteristic and antimicrobial resistance of Staphyloco- ccus aureus ( S. aureus) isolated from children with pneumonia, in order to provide the evidence for clinical diagnosis and treatment. Method:s The S. aureus strains isolated from children diagnosed as S. aureus pneumonia in the Beijing Children′s Hospital, Capital Medical University, between January 2016 and March 2017 were collected.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. S. aureus isolates were characterized by multilocus sequence typing (MLST) and Staphylococcal protein A (spa) typing, and MRSA strains were characterized by Staphylococcal chromosome cassette (SCC mec) typing.Besides, 21 superantigens (SAgs) genes, panton-valentine leucocidin (PVL) genes, adhesion genes fnbb and cna were detected by PCR; E-test was used to detect in vitro drug sensitivity of 14 antibiotics. Result:s A total of 42 S. aureus were collected, and 21 isolates were MSSA, the same to MRSA, while MSSA strains had relatively dispersed typing, with ST25-t078 (14.2%) as the most common one.ST59-SCC mecⅣa-t437 (71.4%) were the most predominant clones of MRSA.Of the 42 isolates, 36 strains (85.7%) had at least 1 superantigen gene, and sek- seq (21.4%) was the main virulence genotype.The ratio of pvl in MRSA strains (52.3%)was significantly higher than that in MSSA strains (14.2%), while the detection rate of fnbB and cna in MRSA(9.5%, 9.5%) was significantly lower than that in MSSA(42.8%, 47.6%), and the differences were statistically significant (all P<0.05). Ninety point four percent (38/42 strains) of the S. aureus isolates were multidrug resistant. Conclusions:In children with S. aureus pneumonia, MRSA has a high detection rate, and its dominant clonotype is ST59-SCC mecⅣa-t437.The pre-valence of superantigen genes and the multidrug resistant rate of S. aureus are relatively high.MRSA strains often carry pvl, while MSSA strains usually carry fnbB and cna gene.
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Objective:To analyze the molecular and virulence characteristics of Staphylococcus aureus ( S. aureus) isolated from neonates. Methods:A total of 189 S. aureus isolates were collected from Beijing Children′s Hospital from January 2013 to October 2019 and analyzed by multilocus sequence typing (MLST), staphylococcal cassette chromosome mec (SCC mec) typing and Spa typing. Panton-valentine leucocidin (PVL)-encoding gene ( pvl) and 21 superantigen virulence genes were also detected. Results:The 189 S. aureus strains were isolated from respiratory secretions ( n=125), pus ( n=55), blood ( n=8) and pleural effusion ( n=1). There were 98 methicillin-susceptible S. aureus (MSSA) belonging to 42 MSSA clones and 91 methicillin-resistant S. aureus (MRSA) belonging to 26 MRSA clones. ST188-t189 and ST59-SCC mecⅣa-t437 were the predominant MSSA and MRSA clones accounting for 11% and 53%, respectively. The prevalence of pvl gene in MRSA isolates was significantly higher than that in MSSA isolates (32% vs 10%, P<0.01). There were 166 isolates (88%) carrying at least one superantigen virulence gene and among the 21 genes, seq and seb were the most common genes accounting for 47% and 43%, respectively. The most common superantigen genotype was seb- sek- seq. The positive rates of superantigen genes in MRSA and MSSA isolates were 85% (77/91) and 90% (88/98), respectively ( P>0.05). Conclusions:The main clones of MRSA and MSSA were different in neonates. ST59-SCC mecⅣa-t437 was the most predominant MRSA clone, while ST188-t189 was the most predominant MSSA clone. MSSA clones were more dispersed. The prevalence of pvl gene in MRSA was higher than that in MSSA. No significant difference in the prevalence of superantigen genes was observed between MRSA and MSSA.
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Pertussis is an acute highly contagious respiratory disease, which is associated with high rate of hospitalization and death in infants and young children.The pathogenesis of severe pertussis has not been elucidated, and there has not been a consistent universal definition in severe pertussis.This article summarizes the present clinical de-finitions of severe pertussis related diagnosis, and the risk factors for death from pertussis.This text could benefit the clinical practice and the further researches, and to contribute to establish a regulation of the diagnosis and treatment of severe pertussis early.
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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.
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Post-traumatic tetanus is the main type of non-neonatal tetanus. To reduce the incidence and mortality rate of tetanus and guide the primary medical institutions to prevent and control tetanus after trauma, National Immunization Planning Technical Working Group of the Chinese Center for Disease Control and Prevention has compiled this document in the reference with Position Paper by World Health Organization, the latest research progress from home and abroad. The guidelines focus on the basic procedures for the prevention and disposition of post-traumatic tetanus, the application of tetanus vaccines and immune preparation, and the pre-exposure immunization in high-risk populations of trauma.
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Pertussis is an acute highly contagious respiratory disease,which is associated with high rate of hospitalization and death in infants and young children.The pathogenesis of severe pertussis has not been elucidated,and there has not been a consistent universal definition in severe pertussis.This article summarizes the present clinical definitions of severe pertussis related diagnosis,and the risk factors for death from pertussis.This text could benefit the clinical practice and the further researches,and to contribute to establish a regulation of the diagnosis and treatment of severe pertussis early.