Objective:This study aims to explore the prevalence,features,and risk factors of lower respiratory tract infections(LRTIs)in the intensive care unit(ICU)of a newly established hospital in Zunyi City.The goal is to dev...Objective:This study aims to explore the prevalence,features,and risk factors of lower respiratory tract infections(LRTIs)in the intensive care unit(ICU)of a newly established hospital in Zunyi City.The goal is to devise strategies for preventing LRTIs in the ICU of new hospitals,thereby mitigating the incidence of nosocomial LRTIs in ICU patients.Methods:A case-control study was conducted from March 2019 to December 2022 to investigate the incidence rate of LRTIs in the ICU of a newly constructed hospital in Zunyi City.Patients with LRTIs constituted the case group,while those without LRTIs constituted the control group,where a 1:1 matching principle was adhered to.A single-factor chi-square(χ2)test was employed to analyze the risk factors,with independent risk factors being explored using a multivariate logistic regression analysis.Results:A total of 169 strains of pathogenic bacteria were isolated,comprising 66.28%gram-negative bacteria,17.75%gram-positive bacteria,and 15.97%fungi.The most prevalent pathogens included Acinetobacter baumannii(43.20%),Candida albicans(10.65%),and Pseudomonas aeruginosa(8.88%).Of the 82 strains infected by multidrug-resistant bacteria in patients with LRTIs,81.7%were carbapenem-resistant Acinetobacter baumannii,9.8%were multidrug-resistant Pseudomonas aeruginosa,and 6.1%were carbapenem-resistant Escherichia coli.Identified risk factors included smoking history,total hospitalization days,ICU stay length,hypoproteinemia,indwelling gastric tube,intubation type,duration of mechanical ventilation,usage of antibacterial drugs,and administration of protein drugs(P<0.05).Multivariate logistic regression analysis demonstrated that these factors were independent risk factors for nosocomial LRTIs in ICU patients(P<0.05).Conclusion:ICU patients in our hospital were mainly infected by carbapenem-resistant Acinetobacter baumannii.To prevent LRTIs in patients,tailored preventive measures should be developed and the rational use of antibacterial drugs should be promoted.展开更多
Objective: To investigate the prevalence of isolated organisms in patients with lower respiratory tract infections and the antibiotic susceptibilities at a tertiary care center. Methods: In this observational and cros...Objective: To investigate the prevalence of isolated organisms in patients with lower respiratory tract infections and the antibiotic susceptibilities at a tertiary care center. Methods: In this observational and cross-sectional analysis, 114 patients admitted in the intensive care unit were enrolled. The endotracheal aspirates and bronchoalveolar lavage were collected. The bacteria were isolated and identified, and finally, antimicrobial sensitive pattern of the isolated bacteria was examined. Results: The prevalence of infection was 72.72% in male patients and 27.28% in females. The predominant bacteria were Klebsiella pneumoniae (37.50%) followed by Acinetobacter spp. (36.36%), Pseudomonas aeruginosa (7.95%),Escherichia coli (6.81%), Proteus mirabilis (2.27%), atypical Escherichia coli (1.13%), Enterococcus spp. (1.13%),Elizabethkingia meningoseptica (1.13%),Staphylococcus aureus (1.13%),Proteus vulgaris (1.13%), Citrobacter freundii (1.13%), and Citrobacter koseri (1.13%). High resistance to cephalosporins (82.18%) was demonstrated in all Gram-negative bacteria. Bacteria showed susceptibility to colistin (88.75%) followed by tigecycline (83.11%), gentamycin (36.18%), and amikacin (49.23%). Conclusions: As the most frequent respiratory organisms, Klebsiella pneumoniae and Acinetobacter spp. have increased resistance to cephalosporins and susceptibility to colistin followed by tigecycline.展开更多
Objective:To examine the effects of human bocavirus type 1(HBoV1)on the course of lower respiratory tract infections in cases of monoinfection and coinfection,and the effects of HBoV1 viral load on the disease in chil...Objective:To examine the effects of human bocavirus type 1(HBoV1)on the course of lower respiratory tract infections in cases of monoinfection and coinfection,and the effects of HBoV1 viral load on the disease in children under six years old hospitalized with a diagnosis of HBoV1-associated lower respiratory tract infections.Methods:Children under six years of age,who were hospitalized with the diagnosis of lower respiratory tract infection due to HBoV1 between 1 January 2021 and 1 January 2022 were included in the study.Laboratory confirmation of the respiratory pathogens was performed using polymerase chain reaction(PCR).Results:Fifty-four(16.4%)children with HBoV1 among 329 children whose PCR was positive with bacterial/viral agent in nasopharyngeal swab samples were included in the study.There were 28(51.9%)males and 26(48.1%)females with a median age 23.4 months[interquartile range(IQR):13.2,30.0 months](min-max:1 month-68 months).HBoV1 was detected as a monoinfecton in 26(48.1%)children,and as a coinfection with other respiratory agents in 28 children(51.9%).In multiple regression analysis,coinfection(P=0.032)was associated with the length of hospitalization(P<0.001;R^(2)=0.166).There was a negative correlation(r=−0.281,P=0.040)between cough and cycle threshold.Fever was found to be positively correlated with C-reactive protein(r=0.568,P<0.001)and procalcitonin(r=0.472;P=0.001).Conclusions:Although we found a higher HBoV1 viral load in children with more cough symptoms in our study,it had no effect on the severity of the disease,such as length of hospital stay and need for intensive care.Coinfection was found to affect the length of hospitalization.展开更多
BACKGROUND The association between hospitalization for human respiratory syncytial virus(HRSV)bronchiolitis in early childhood and subsequent asthma is well established.The long-term prognosis for non-bronchiolitis lo...BACKGROUND The association between hospitalization for human respiratory syncytial virus(HRSV)bronchiolitis in early childhood and subsequent asthma is well established.The long-term prognosis for non-bronchiolitis lower respiratory tract infections(LRTI)caused by viruses different from HRSV and rhinovirus,on the other hand,has received less interest.AIM To investigate the relationship between infant LRTI and later asthma and examine the influence of confounding factors.METHODS The PubMed and Global Index Medicus bibliographic databases were used to search for articles published up to October 2021 for this systematic review.We included cohort studies comparing the incidence of asthma between patients with and without LRTI at≤2 years regardless of the virus responsible.The meta-analysis was performed using the random effects model.Sources of heterogeneity were assessed by stratified analyses.RESULTS This review included 15 articles(18 unique studies)that met the inclusion criteria.LRTIs at≤2 years were associated with an increased risk of subsequent asthma up to 20 years[odds ratio(OR)=5.0,95%CI:3.3-7.5],with doctor-diagnosed asthma(OR=5.3,95%CI:3.3-8.6),current asthma(OR=5.4,95%CI:2.7-10.6),and current medication for asthma(OR=1.2,95%CI:0.7-3.9).Our overall estimates were not affected by publication bias(P=0.671),but there was significant heterogeneity[I 2=58.8%(30.6-75.5)].Compared to studies with hospitalized controls without LRTI,those with ambulatory controls had a significantly higher strength of association between LRTIs and subsequent asthma.The strength of the association between LRTIs and later asthma varied significantly by country and age at the time of the interview.The sensitivity analyses including only studies with similar proportions of confounding factors(gender,age at LRTI development,age at interview,gestational age,birth weight,weight,height,smoking exposure,crowding,family history of atopy,and family history of asthma)between cases and controls did not alter the overall estimates.CONCLUSION Regardless of the causative virus and confounding factors,viral LRTIs in children<2 years are associated with an increased risk of developing a subsequent asthma.Parents and pediatricians should be informed of this risk.展开更多
Objective:To use the gene chip of pseudomonas aeruginosa as a research sample and to explore it at an omics level,aiming at elucidating the co-expression network characteristics of the virulence genes exoS and exoU of...Objective:To use the gene chip of pseudomonas aeruginosa as a research sample and to explore it at an omics level,aiming at elucidating the co-expression network characteristics of the virulence genes exoS and exoU of pseudomonas aeruginosa in the lower respiratory tract from the perspective of molecular biology and identifying its key regulatory genes.Methods:From March 2016 to May 2018,312 patients infected with pseudomonas aeruginosa in the lower respiratory tract who were admitted to Department of Respiratory Medicine of Baogang Hospital and given follow-up treatments in the hospital were selected as subjects by use of cluster sampling.Alveolar lavage fluid and sputum collected from those patients were used as biological specimens.The genes of pseudomonas aeruginosa were detected with the help of oligonucleotide probes to make a pre-processing of chip data.A total of 8 common antibiotics(ceftazidime,gentamicin,piperacillin,amikacin,ciprofloxacin,levofloxacin,doripenem and ticarcillin)against Gram-negative bacteria were selected to determine the drug resistance of biological specimens.MCODE algorithm was used to construct a co-expression network model of the drug-resistance genes focused on exoS/exoU.Results:The expression level of exoS/exoU in the drug-resistance group was significantly higher than that in the non-resistance group(p<0.05).The top 5 differentially expressed genes in the alveolar lavage fluid specimens from the drug-resistance group were RAC1,ITGB1,ITGB5,CRK and IGF1R in the order from high to low.In the sputum specimens,the top 5 differentially expressed genes were RAC1,CRK,IGF1R,ITGB1 and ITGB5.In the alveolar lavage fluid specimens,only RAC1 had a positive correlation with the expression of exoS and exoU(p<0.05).In the sputum specimens,RAC1,ITGB1,ITGB5,CRK and IGF1R were positively correlated with the expression of exoS and exoU(p<0.05).The genes included in the co-expression network contained exoS,exoU,RAC1,ITGB1,ITGB5,CRK,CAMK2D,RHOA,FLNA,IGF1R,TGFBR2 and FOS.Among them,RAC1 had a highest score in the aspect of regulatory ability(72.00)and the largest number of regulatory genes(6);followed by ITGB1,ITGB5 and CRK genes.Conclusions:The high expression of exoS and exoU in the sputum specimens suggests that pseudomonas aeruginosa has a higher probability to get resistant to antibiotics;RAC1,ITGB1,ITGB5 and CRK genes may be the key genes that can regulate the expression of exoS and exoU.展开更多
Human metapneumovirus(HMPV) infection is one of the leading causes of hospitalization in young children with acute respiratory illness. In this study, we prospectively collected respiratory tract samples from children...Human metapneumovirus(HMPV) infection is one of the leading causes of hospitalization in young children with acute respiratory illness. In this study, we prospectively collected respiratory tract samples from children who were hospitalized with acute lower respiratory tract infection in six hospitals in China from 2017 to 2019. HMPV was detected in 145 out of 2733 samples(5.3%) from the hospitalized children. The majority of HMPV-positive children were under the age of two(67.6%), with a median age of one year. HMPV can independently cause acute lower respiratory tract infection in young children, while all patients showed mild clinical symptoms. Of all the co-infected patients, HMPV was most commonly detected with enterovirus(EV) or rhinovirus(RhV)(38.0%),followed by respiratory syncytial virus(RSV)(32.0%). The highest detection rate occurred from March to May in both northern and southern China. Out of 145 HMPV positive samples, 48 were successfully typed, of which 36strains were subgrouped into subtypes A2c(75%), eight strains were included in subtype B1(16.7%), and four strains were included in subtype B2(8.3%). Moreover, 16 A2c strains contained 111-nucleotide duplications in the G gene. Twenty-seven complete HMPV genomes were successfully obtained, and 25(92.6%) strains belonged to subtype A2c, whereas one strain was included in subgroup B1 and another was included in subgroup B2. A total of 277 mutations were observed in the complete genomes of 25 A2c strains. All results presented here improve our understanding of clinical characteristics and molecular epidemiology of HMPV infection in children.展开更多
Human respiratory syncytial virus(RSV) is a major pathogen of acute lower respiratory tract infection among young children. To investigate the prevalence and genetic characteristics of RSV in China, we performed a mol...Human respiratory syncytial virus(RSV) is a major pathogen of acute lower respiratory tract infection among young children. To investigate the prevalence and genetic characteristics of RSV in China, we performed a molecular epidemiological study during 2015–2019. A total of 964 RSV-positive specimens were identified from 5529 enrolled patients during a multi-center study. RSV subgroup A(RSV-A) was the predominant subgroup during this research period except in2016. Totally, 535 sequences of the second hypervariable region(HVR-2) of the G gene were obtained. Combined with182 Chinese sequences from GenBank, phylogenetic trees showed that 521 RSV-A sequences fell in genotypes ON1(512),NA1(6) and GA5(3), respectively;while 196 RSV-B sequences fell in BA9(193) and SAB4(3). ON1 and BA9 were the only genotypes after December 2015. Genotypes ON1 and BA9 can be separated into 10 and 7 lineages, respectively. The HVR-2 of genotype ON1 had six amino acid changes with a frequency more than 10%, while two substitutions H258 Q and H266 L were co-occurrences. The HVR-2 of genotype BA9 had nine amino acid substitutions with a frequency more than10%, while the sequences with T290 I and T312 I were all from 2018 to 2019. One N-glycosylation site at 237 was identified among ON1 sequences, while two N-glycosylation sites(296 and 310) were identified in the 60-nucleotide duplication region of BA9. To conclusion, ON1 and BA9 were the predominant genotypes in China during 2015–2019. For the genotypes ON1 and BA9, the G gene exhibited relatively high diversity and evolved continuously.展开更多
Objective:To determine the appropriate treatment regimen and the clinical course of the lower respiratory tract infections(RTIs)and to detect the common viral causes of lower RTIs.Methods:The present study included a ...Objective:To determine the appropriate treatment regimen and the clinical course of the lower respiratory tract infections(RTIs)and to detect the common viral causes of lower RTIs.Methods:The present study included a total of 255 pediatric patients aged less than 7 years old and admitted to the Department of Pediatrics of Rize Training and Research Hospital between January 2014 and January 2015 with clinical pre-diagnosis of lower RTI.Nasopharyngeal swab specimens collected from these patients were tested for viral pathogens by using multiplex RTPCR kit the ResPlex II plus Panel PRE(Qiagen,Germany).Results:A total of 212 out of 255(83.1%)specimens revealed positive for one or more viral pathogens.The most common detected pathogens were respiratory syncytial virus(RSV)A/B in 110 samples(43.1%),rhinovirus in 51 samples(20.0%),adenovirus in 36 samples(14.1%),influenzae virus A in 32 samples(12.5%),and coronavirus in 24 samples(9.4%).In 76 samples(29.8%),more than one viral pathogen were detected.RSV was seen in more than 50%patients in the first 2 years.RSV was the most common pathogen in each year of the first 5 years but rhinovirus,influenza A and adenovirus were seen more than RSV after the fifth year.A total of 95.8%of the viral detections were seen between November and April without a significant peak amongst these months.The distribution of the pathogens by months of the year showed no significance.Conclusions:These findings can contribute to epidemiological data of Turkey.Detection of the viral pathogens causing lower RTIs can be critical in management of the disease,decrease inappropriate antibiotic treatment,and lower the morbidity and mortality rates in such diseases.展开更多
Objective To study the genotyping characteristics and antibiotic resistance of methicillin-resistant Staphylococcus aureus(MRSA)isolated from lower respiratory tract at 2 different level hospitals in Shanghai.Methods ...Objective To study the genotyping characteristics and antibiotic resistance of methicillin-resistant Staphylococcus aureus(MRSA)isolated from lower respiratory tract at 2 different level hospitals in Shanghai.Methods The subjects included 155 patients at Ruijin Hospital and Tongren Hospital between January 2013 and June 2014,including 108 males and 47 females,with a mean age展开更多
基金Analysis of influencing factors and direct economic losses of ICU infection in a newly built tertiary comprehensive hospital(Project No:Qiankehe Support[2021]General 043)。
文摘Objective:This study aims to explore the prevalence,features,and risk factors of lower respiratory tract infections(LRTIs)in the intensive care unit(ICU)of a newly established hospital in Zunyi City.The goal is to devise strategies for preventing LRTIs in the ICU of new hospitals,thereby mitigating the incidence of nosocomial LRTIs in ICU patients.Methods:A case-control study was conducted from March 2019 to December 2022 to investigate the incidence rate of LRTIs in the ICU of a newly constructed hospital in Zunyi City.Patients with LRTIs constituted the case group,while those without LRTIs constituted the control group,where a 1:1 matching principle was adhered to.A single-factor chi-square(χ2)test was employed to analyze the risk factors,with independent risk factors being explored using a multivariate logistic regression analysis.Results:A total of 169 strains of pathogenic bacteria were isolated,comprising 66.28%gram-negative bacteria,17.75%gram-positive bacteria,and 15.97%fungi.The most prevalent pathogens included Acinetobacter baumannii(43.20%),Candida albicans(10.65%),and Pseudomonas aeruginosa(8.88%).Of the 82 strains infected by multidrug-resistant bacteria in patients with LRTIs,81.7%were carbapenem-resistant Acinetobacter baumannii,9.8%were multidrug-resistant Pseudomonas aeruginosa,and 6.1%were carbapenem-resistant Escherichia coli.Identified risk factors included smoking history,total hospitalization days,ICU stay length,hypoproteinemia,indwelling gastric tube,intubation type,duration of mechanical ventilation,usage of antibacterial drugs,and administration of protein drugs(P<0.05).Multivariate logistic regression analysis demonstrated that these factors were independent risk factors for nosocomial LRTIs in ICU patients(P<0.05).Conclusion:ICU patients in our hospital were mainly infected by carbapenem-resistant Acinetobacter baumannii.To prevent LRTIs in patients,tailored preventive measures should be developed and the rational use of antibacterial drugs should be promoted.
文摘Objective: To investigate the prevalence of isolated organisms in patients with lower respiratory tract infections and the antibiotic susceptibilities at a tertiary care center. Methods: In this observational and cross-sectional analysis, 114 patients admitted in the intensive care unit were enrolled. The endotracheal aspirates and bronchoalveolar lavage were collected. The bacteria were isolated and identified, and finally, antimicrobial sensitive pattern of the isolated bacteria was examined. Results: The prevalence of infection was 72.72% in male patients and 27.28% in females. The predominant bacteria were Klebsiella pneumoniae (37.50%) followed by Acinetobacter spp. (36.36%), Pseudomonas aeruginosa (7.95%),Escherichia coli (6.81%), Proteus mirabilis (2.27%), atypical Escherichia coli (1.13%), Enterococcus spp. (1.13%),Elizabethkingia meningoseptica (1.13%),Staphylococcus aureus (1.13%),Proteus vulgaris (1.13%), Citrobacter freundii (1.13%), and Citrobacter koseri (1.13%). High resistance to cephalosporins (82.18%) was demonstrated in all Gram-negative bacteria. Bacteria showed susceptibility to colistin (88.75%) followed by tigecycline (83.11%), gentamycin (36.18%), and amikacin (49.23%). Conclusions: As the most frequent respiratory organisms, Klebsiella pneumoniae and Acinetobacter spp. have increased resistance to cephalosporins and susceptibility to colistin followed by tigecycline.
文摘Objective:To examine the effects of human bocavirus type 1(HBoV1)on the course of lower respiratory tract infections in cases of monoinfection and coinfection,and the effects of HBoV1 viral load on the disease in children under six years old hospitalized with a diagnosis of HBoV1-associated lower respiratory tract infections.Methods:Children under six years of age,who were hospitalized with the diagnosis of lower respiratory tract infection due to HBoV1 between 1 January 2021 and 1 January 2022 were included in the study.Laboratory confirmation of the respiratory pathogens was performed using polymerase chain reaction(PCR).Results:Fifty-four(16.4%)children with HBoV1 among 329 children whose PCR was positive with bacterial/viral agent in nasopharyngeal swab samples were included in the study.There were 28(51.9%)males and 26(48.1%)females with a median age 23.4 months[interquartile range(IQR):13.2,30.0 months](min-max:1 month-68 months).HBoV1 was detected as a monoinfecton in 26(48.1%)children,and as a coinfection with other respiratory agents in 28 children(51.9%).In multiple regression analysis,coinfection(P=0.032)was associated with the length of hospitalization(P<0.001;R^(2)=0.166).There was a negative correlation(r=−0.281,P=0.040)between cough and cycle threshold.Fever was found to be positively correlated with C-reactive protein(r=0.568,P<0.001)and procalcitonin(r=0.472;P=0.001).Conclusions:Although we found a higher HBoV1 viral load in children with more cough symptoms in our study,it had no effect on the severity of the disease,such as length of hospital stay and need for intensive care.Coinfection was found to affect the length of hospitalization.
基金Supported by the European Union (EDCTP2 Programme),No. TMA2019PF-2705
文摘BACKGROUND The association between hospitalization for human respiratory syncytial virus(HRSV)bronchiolitis in early childhood and subsequent asthma is well established.The long-term prognosis for non-bronchiolitis lower respiratory tract infections(LRTI)caused by viruses different from HRSV and rhinovirus,on the other hand,has received less interest.AIM To investigate the relationship between infant LRTI and later asthma and examine the influence of confounding factors.METHODS The PubMed and Global Index Medicus bibliographic databases were used to search for articles published up to October 2021 for this systematic review.We included cohort studies comparing the incidence of asthma between patients with and without LRTI at≤2 years regardless of the virus responsible.The meta-analysis was performed using the random effects model.Sources of heterogeneity were assessed by stratified analyses.RESULTS This review included 15 articles(18 unique studies)that met the inclusion criteria.LRTIs at≤2 years were associated with an increased risk of subsequent asthma up to 20 years[odds ratio(OR)=5.0,95%CI:3.3-7.5],with doctor-diagnosed asthma(OR=5.3,95%CI:3.3-8.6),current asthma(OR=5.4,95%CI:2.7-10.6),and current medication for asthma(OR=1.2,95%CI:0.7-3.9).Our overall estimates were not affected by publication bias(P=0.671),but there was significant heterogeneity[I 2=58.8%(30.6-75.5)].Compared to studies with hospitalized controls without LRTI,those with ambulatory controls had a significantly higher strength of association between LRTIs and subsequent asthma.The strength of the association between LRTIs and later asthma varied significantly by country and age at the time of the interview.The sensitivity analyses including only studies with similar proportions of confounding factors(gender,age at LRTI development,age at interview,gestational age,birth weight,weight,height,smoking exposure,crowding,family history of atopy,and family history of asthma)between cases and controls did not alter the overall estimates.CONCLUSION Regardless of the causative virus and confounding factors,viral LRTIs in children<2 years are associated with an increased risk of developing a subsequent asthma.Parents and pediatricians should be informed of this risk.
文摘Objective:To use the gene chip of pseudomonas aeruginosa as a research sample and to explore it at an omics level,aiming at elucidating the co-expression network characteristics of the virulence genes exoS and exoU of pseudomonas aeruginosa in the lower respiratory tract from the perspective of molecular biology and identifying its key regulatory genes.Methods:From March 2016 to May 2018,312 patients infected with pseudomonas aeruginosa in the lower respiratory tract who were admitted to Department of Respiratory Medicine of Baogang Hospital and given follow-up treatments in the hospital were selected as subjects by use of cluster sampling.Alveolar lavage fluid and sputum collected from those patients were used as biological specimens.The genes of pseudomonas aeruginosa were detected with the help of oligonucleotide probes to make a pre-processing of chip data.A total of 8 common antibiotics(ceftazidime,gentamicin,piperacillin,amikacin,ciprofloxacin,levofloxacin,doripenem and ticarcillin)against Gram-negative bacteria were selected to determine the drug resistance of biological specimens.MCODE algorithm was used to construct a co-expression network model of the drug-resistance genes focused on exoS/exoU.Results:The expression level of exoS/exoU in the drug-resistance group was significantly higher than that in the non-resistance group(p<0.05).The top 5 differentially expressed genes in the alveolar lavage fluid specimens from the drug-resistance group were RAC1,ITGB1,ITGB5,CRK and IGF1R in the order from high to low.In the sputum specimens,the top 5 differentially expressed genes were RAC1,CRK,IGF1R,ITGB1 and ITGB5.In the alveolar lavage fluid specimens,only RAC1 had a positive correlation with the expression of exoS and exoU(p<0.05).In the sputum specimens,RAC1,ITGB1,ITGB5,CRK and IGF1R were positively correlated with the expression of exoS and exoU(p<0.05).The genes included in the co-expression network contained exoS,exoU,RAC1,ITGB1,ITGB5,CRK,CAMK2D,RHOA,FLNA,IGF1R,TGFBR2 and FOS.Among them,RAC1 had a highest score in the aspect of regulatory ability(72.00)and the largest number of regulatory genes(6);followed by ITGB1,ITGB5 and CRK genes.Conclusions:The high expression of exoS and exoU in the sputum specimens suggests that pseudomonas aeruginosa has a higher probability to get resistant to antibiotics;RAC1,ITGB1,ITGB5 and CRK genes may be the key genes that can regulate the expression of exoS and exoU.
基金funded by the National Natural Science Foundation of China(82172275)the CAMS Innovation Fund for Medical Sciences,China(CIFMS,2019-I2M-5-026)
文摘Human metapneumovirus(HMPV) infection is one of the leading causes of hospitalization in young children with acute respiratory illness. In this study, we prospectively collected respiratory tract samples from children who were hospitalized with acute lower respiratory tract infection in six hospitals in China from 2017 to 2019. HMPV was detected in 145 out of 2733 samples(5.3%) from the hospitalized children. The majority of HMPV-positive children were under the age of two(67.6%), with a median age of one year. HMPV can independently cause acute lower respiratory tract infection in young children, while all patients showed mild clinical symptoms. Of all the co-infected patients, HMPV was most commonly detected with enterovirus(EV) or rhinovirus(RhV)(38.0%),followed by respiratory syncytial virus(RSV)(32.0%). The highest detection rate occurred from March to May in both northern and southern China. Out of 145 HMPV positive samples, 48 were successfully typed, of which 36strains were subgrouped into subtypes A2c(75%), eight strains were included in subtype B1(16.7%), and four strains were included in subtype B2(8.3%). Moreover, 16 A2c strains contained 111-nucleotide duplications in the G gene. Twenty-seven complete HMPV genomes were successfully obtained, and 25(92.6%) strains belonged to subtype A2c, whereas one strain was included in subgroup B1 and another was included in subgroup B2. A total of 277 mutations were observed in the complete genomes of 25 A2c strains. All results presented here improve our understanding of clinical characteristics and molecular epidemiology of HMPV infection in children.
基金This work was supported by the National Science and Technology Major Projects(Grant Number 2017ZX10104001-005-010,2017ZX10103004-004)the CAMS Innovation Fund for Medical Sciences(CIFMS)(Grant Number 2019-I2M-5-026)。
文摘Human respiratory syncytial virus(RSV) is a major pathogen of acute lower respiratory tract infection among young children. To investigate the prevalence and genetic characteristics of RSV in China, we performed a molecular epidemiological study during 2015–2019. A total of 964 RSV-positive specimens were identified from 5529 enrolled patients during a multi-center study. RSV subgroup A(RSV-A) was the predominant subgroup during this research period except in2016. Totally, 535 sequences of the second hypervariable region(HVR-2) of the G gene were obtained. Combined with182 Chinese sequences from GenBank, phylogenetic trees showed that 521 RSV-A sequences fell in genotypes ON1(512),NA1(6) and GA5(3), respectively;while 196 RSV-B sequences fell in BA9(193) and SAB4(3). ON1 and BA9 were the only genotypes after December 2015. Genotypes ON1 and BA9 can be separated into 10 and 7 lineages, respectively. The HVR-2 of genotype ON1 had six amino acid changes with a frequency more than 10%, while two substitutions H258 Q and H266 L were co-occurrences. The HVR-2 of genotype BA9 had nine amino acid substitutions with a frequency more than10%, while the sequences with T290 I and T312 I were all from 2018 to 2019. One N-glycosylation site at 237 was identified among ON1 sequences, while two N-glycosylation sites(296 and 310) were identified in the 60-nucleotide duplication region of BA9. To conclusion, ON1 and BA9 were the predominant genotypes in China during 2015–2019. For the genotypes ON1 and BA9, the G gene exhibited relatively high diversity and evolved continuously.
文摘Objective:To determine the appropriate treatment regimen and the clinical course of the lower respiratory tract infections(RTIs)and to detect the common viral causes of lower RTIs.Methods:The present study included a total of 255 pediatric patients aged less than 7 years old and admitted to the Department of Pediatrics of Rize Training and Research Hospital between January 2014 and January 2015 with clinical pre-diagnosis of lower RTI.Nasopharyngeal swab specimens collected from these patients were tested for viral pathogens by using multiplex RTPCR kit the ResPlex II plus Panel PRE(Qiagen,Germany).Results:A total of 212 out of 255(83.1%)specimens revealed positive for one or more viral pathogens.The most common detected pathogens were respiratory syncytial virus(RSV)A/B in 110 samples(43.1%),rhinovirus in 51 samples(20.0%),adenovirus in 36 samples(14.1%),influenzae virus A in 32 samples(12.5%),and coronavirus in 24 samples(9.4%).In 76 samples(29.8%),more than one viral pathogen were detected.RSV was seen in more than 50%patients in the first 2 years.RSV was the most common pathogen in each year of the first 5 years but rhinovirus,influenza A and adenovirus were seen more than RSV after the fifth year.A total of 95.8%of the viral detections were seen between November and April without a significant peak amongst these months.The distribution of the pathogens by months of the year showed no significance.Conclusions:These findings can contribute to epidemiological data of Turkey.Detection of the viral pathogens causing lower RTIs can be critical in management of the disease,decrease inappropriate antibiotic treatment,and lower the morbidity and mortality rates in such diseases.
文摘Objective To study the genotyping characteristics and antibiotic resistance of methicillin-resistant Staphylococcus aureus(MRSA)isolated from lower respiratory tract at 2 different level hospitals in Shanghai.Methods The subjects included 155 patients at Ruijin Hospital and Tongren Hospital between January 2013 and June 2014,including 108 males and 47 females,with a mean age
