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Objective:To analyze the current status of neonatal nosocomial infection research at home and abroad, explore its research hotspots and development trends, and provide evidence for further research on the prevention and treatment of neonatal nosocomial infection.Methods:The Chinese and English literature related to neonatal nosocomial infection included in CNKI and Web of Science Database from 2010 to 2021 were searched, and CiteSpace 6.1.R2 and VOSviewer1.6.18 software were used to map the authors, institutions, countries, and keywords of the included literature. At the same time, the burst item map was used to predict the future research development trends to a certain extent.Results:A total of 235 authors and 2 core teams of Chinese literature (1 639 articles), 157 authors and 2 core teams of English literature (1 322 articles) were analyzed. 659 Chinese keywords and 1 330 English keywords were extracted, including "nosocomial infection", "risk factors", "infection", "epidemiology", etc. From these literature, 13 Chinese literature clusters and 6 English clusters were generated, and the clustering results were significant and reasonable. The current research hotspots in China focused on pregnancy outcomes and nursing management, while the hotspots of foreign researches focused on sequelae and disease burden.Conclusions:Compared with international research, domestic research on neonatal nosocomial infection hasn't combined with social, environmental and other related factors, while international research teams have begun to shift the focus of research on neonatal nosocomial infections to disease burden and infection sequelae. In the future, cooperation between domestic and foreign research teams should be strengthened, focusing on the frontier trend of international research, and improving the depth and breadth of research.
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Objective To investigate clinical features and detect mutations in a case of tuberous sclerosis complex (TSC) caused by a somatic mosaic mutation in the TSC2 gene.Methods Peripheral blood samples were obtained from a patient with suspected TSC,his parents,and 200 unrelated healthy controls.Genomic DNA was extracted from these blood samples,polymerase chain reaction (PCR)and nextgeneration sequencing were performed to amplify all the exons and their flanking sequences of the TSC 1 and TSC2 genes followed by DNA sequencing,so as to identify mutations in the TSC 1 and TSC2 genes.DNA was also extracted from lesional skin tissues of the patient,and PCR was conducted to amplify the target fragment of the TSC2 gene followed by DNA sequencing.Results The patient clinically presented with facial angiofibroma,depigmented patches on the waist,periungual fibroma and angioleio-myolipoma of the kidney,which were consistent with the diagnosis of TSC.A mutation c.5130_5131insT(p.V1711Cfs* 18) was identified in the TSC2 gene in the patient.A higher frequency of the mutation was found in the DNA of the tumor tissue than in that of the peripheral blood.No such a mutation was found in his parents'DNA,unrelated healthy controls or any public database.Conclusion The somatic mosaic mutation c.5130_513 1insT in the TSC2 gene is responsible for the phenotype of TSC in the patient.
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Objective To investigate the antimicrobial resistant mechanisms of high level carbapenem resistant Klebsiella pneumoniae infection of burn patients .Methods A retrospective study was conducted on totally 18 non-repetitive high level CR-KP which were isolated from burn patients hospitalized between July 2014 and June 2015.MIC of antibiotics were determined by using the GN 13 cards and agar dilution method.The specific PCR and DNA sequence analysis were performed to confirm the β-lactamase type.Plasmid conjugation transfer experiments and southem hybridization were applied to study the mode of carbapenem resistance transmission .Outer membrane proteins ( Omps) were isolated and examined by PCR and ( sodium dodecyl sulfate polyacrylamide gel electrophores ) SDS-PAGE.Pulsed-field gel electrophoresis( PFGE ) and Multilocus sequence typing ( MLST ) was used to determine the genotypes . Results Susceptibility of antimicrobial agents indicated that all these strains with multiple drug resistance . The resistance rate to piperacillin/tazobactam, ceftriaxone, levofloxacin, ciprofloxacin, gentamicin, tobramycin, cefotetan, ceftazidime, cefepime, aztreonam, imipenem, and meropenem was 100％ (18/18).Moreover, the resistance rate of CR-KP isolates to amikacin was 72.2％ ( 13/18 ) , compound sulfamethoxazole was 61.1％(11/18), tigecycline was 0％(0/18).Conjugation study with Escherictda coli J53 resulted in the transfer of significant reduced carbapenem susceptibility from donors (MICs increased at least 8-fold).By PCR, eighteen strains of Klebsiella pneumoniae carried NDM-1 gene, 5 strains carried KPC-2 gene.The blaNDM-1 was transferable by plasmids.Southern blot hybridization indicated that the blaNDM-1 gene was located on plasmid in size of 46 kb.The plasmid belonged to incompatibility group IncX 3.Seven types of CR-KP were detected by PFGE.In addition, MLST assigned them to sequence type ( ST)11, ST395, ST17, ST37, ST263, ST14 and ST76 types.SDS-PAGE and ompK35/36 genes sequence analysis of Omp indicated that there was absence of outer membrane proteins OmpK 36 in ST11, ST395, ST37 strains.However, the other STs strains expressed lower quantities of OmpK 36.Conclusions High level carbapenem resistance in K.pneumoniae causing infection in burn patients is attributable to production of plasmid-mediated metallo· β-laetamase NDM-1 combined with porin OmpK36 deficiency or low expression .The K.pneumoniae with NDM-1 and KPC-2 carbapenemase were detected .
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Objective To explore the constitute and antimicrobial susceptibility of pathogenic fungi causing candidemia in Nanchang City of Jiangxi Province.Methods Candida spp.isolated from blood specimens of patients at a hospital in Nanchang in March-October 2015 were collected, fungal strains were identified by amplifying the internal transcribed spacer (ITS) and large ribosomal subunit (D1/D2 region of 26rRNA), antifungal susceptibility of fungi was detected.Results A total of 1 332 positive blood culture specimens were collected, including 74 fungal positive specimens, accounting for 5.56％, 52 strains of Candida spp.were obtained, most were Candida tropicalis (n=17,32.69％),followed by Candida albicans(n=16, 30.77％) and Candida parapsilosis complex (n=16, 30.77％).Identification results of ITS and D1/D2 region were identical.52 strains of Candida spp.were sensitive to both micafungin and caspofungin, epidemiological cutoff value(ECV) of amphotericin B showed that 52 strains were all wild type.Resistance rates of Candida tropicalis to fluconazole and voriconazole were 29.41％ and 17.64％ respectively, ECV of itraconazole and posaconazole showed that wild type accounted for 82.35％ and 94.12％ respectively;resistance rates of Candida albicans to fluconazol and voriconazole were 93.75％ and 81.25％ respectively, ECV of itraconazole and posaconazole showed that wild type accounted for 75.00％ and 81.25％ respectively;Candida parapsilosis complex strains were sensitive to both fluconazole and voriconazole, ECV of itraconazole and posaconazole showed that all were wild type;all Candida glabrata strains had intermediate resistance rates to fluconazole, ECV of voriconazole, itraconazole, and posaconazole showed that wild type accounted for 66.67％, 100.00％, and 100.00％ respectively.Conclusion Candida tropicalis is the most common pathogenic fungus causing candidemia in Nanchang of Jiangxi, followed by Candida albicans and Candida parapsilosis complex.Azole, echinocandin, and amphotericin B are still first-line antifungal agents.
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Objective To investigate the occurrence of postoperative healthcare-associated infection(HAI)and its risk factors in neurosurgical patients undergoing removal of intracranial tumor,so as to provide theoretical basis for formulating intervention measures.Methods Prospective survey was adopted to monitor the occurrence of postoperative HAI in patients who admitted to the department of neurosurgery of a hospital and underwent selective removal of intracranial tumor between April 2013 and December 2014 ,risk factors for HAI were analyzed with univariate and multivariate logistic regression analysis.Results A total of 1 218 patients were surveyed,163 patents developed 193 times of postoperative HAI,inci-dence of postoperative HAI was 13.38%,case incidence of HAI was 15.85%.The main HAI site was intracranial site(n=125,64.77%),the next was lower respiratory tract (n=55,28.49%).Multivariate logistic regression analysis showed that operation grade and subtentorial operation were independent risk factors for postoperative HAI in neurosurgical patients undergoing removal of intracranial tumor,OR and 95%CI were 4.352(1.878-10.080)and 1.812(1.280-2.564)respec-tively.Conclusion Risk of postoperative HAI in neurosurgical patients undergoing high grade operation and subtentorial removal of intracranial tumor is high,effective prevention and control measures should be taken to prevent the occurrence of HAI.
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Objective To identify mutations in the OSMR gene in a pedigree with familial primary cutaneous amyloidosis (FPCA).Methods Clinical data were collected from a pedigree with FPCA.Peripheral blood samples were obtained from the proband,his 19 relatives,and 50 unrelated healthy human controls.Genomic DNA was extracted from these blood samples,and subjected to PCR for the amplification of 18 encoding exons and their flanking sequences of the OSMR gene followed by DNA sequencing.Results A heterozygous missense mutation c.2081C ＞ T,which leads to the substitution of proline by threonine at position 694,was detected in the OSMR gene of the proband and his affected relatives,but not in unaffected relatives or healthy controls.Conclusion The heterozygous mutation p.P694L in the OSMR gene may cause the clinical phenotype of FPCA in this family.
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Objective To investigate the molecule phenotype, epidemiology, and resistance genes of the New Delhi metallo- β-lactamase-1 ( NDM-1 ) producing Klebsiella pneumoniae ( K. pneumoniae ) . Methods Retrospective study was made on one hundred and ten non-repetitive carbepenem-resistant K. pneumoniae clinical isolated strains, which were collected from January 2011 to December 2012 in our hospital. The minimal inhibitory concentrations ( MICs ) of antibiotics were tested by the GN13 cards of BioMerieux Company. Modified Hodge test were used for the detection of carbapenemases. The blaNDM-1 encoding gene and linkage of ISAba125-NDM were detected by PCR method. The purified PCR products were cloned and sequenced. The homology of the K. pneumoniae were analyzed by the multilocus sequence typing ( MLST ) . Plasmid conjugation experiment and curing method were used to study the transfer of bacterial resistance. The Fisher′s exact probability test was used to compare the data. Results 13% NDM-1-producing K. pneumoniae were detected and confirmed as blaNDM-1 by sequencing (14/110). The resistance rates of the 14 NDM-1-producing K. pneumoniae strains to imipenem, meropenem, ertapenem, ciprofloxacin, levofloxacin, amikacin, and aztreonam were 14/14, 14/14, 13/14, 10/14, 9/14, 5/14, and 11/14. Meanwhile, the positive rate of ISAba125-NDM linkage of those 14 NDM-1-producing K. pneumoniae strains was 14/14. The E. coli J53 transconjugants, whose MICs of imipenem, meropenem, and ertapenem were increased by 4 to 64 times, were blaNDM-1 gene and ISAba125-NDM linkage positive. In addition, it was showed that the blaNDM-1 gene and ISAba125-NDM linkage were located on a plasmid with a size of approximately 65 000 bp. Conclusions The NDM-1 producing K. pneumoniae strains in this study were resistant to many commonly used antibiotics, however, the resistance rate to aminoglycoside and aztreonam were relatively low. The carbapenemase-resistant genotype spread by blaNDM-1 carried plasmid. Attention should be paid to its easily transmissible feature among the strains in clinic. The insertion sequence ISAba125 may be involved in the blaNDM-1 gene mediated carbapenemase-resistant genotype.
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<p><b>OBJECTIVE</b>To study the resistance mechanism and homology of carbapenems-resistant Pseudomonas aeruginosa (PA).</p><p><b>METHODS</b>A total of 812 strains of PA (identified) were isolated from sputum, urine, blood, pus, and drainage of patients with burn, severe pneumonia, diabetes, chronic obstructive pneumonia, myocarditis, liver transplantation, or brainstem hemorrhage hospitalized from January to September 2012. Drug resistance of the 812 strains of PA to 15 antibiotics commonly used in clinic, including piperacillin, imipenem, etc., was tested using the automatic microorganism identifying and drug sensitivity analyzer. Among the carbapenems-resistant PA isolates, synergism test with imipenem-ethylene diamine tetraacetic acid (EDTA) and enhancement test with imipenem-EDTA and ceftazidime-EDTA were used to screen metallo-β-lactamase (MBL)-producing strains; modified Hodge test was used to screen strains producing Klebsiella pneumoniae carbapenemases (KPC); the carbapenemase gene, plasmid mediated quinolone resistant (PMQR) gene, and mobile genetic elements (MGE) were detected by polymerase chain reaction (PCR). In addition, a comparative analysis of the PMQR gene carrying level between the carbapenemase gene positive strains and carbapenemase gene negative strains was carried out. The repetitive consensus sequence of Enterobacteriaceae genome PCR (ERIC-PCR) was carried out for gene typing. Moreover, the source and resistance genes of strains with the same genotype were analyzed. Data were processed with Fisher's exact probability test.</p><p><b>RESULTS</b>The sensitive rates of the 812 strains of PA to ceftriaxone and trimethoprim-sulfamethoxazole were high, respectively 83.07% and 88.19%, and those of the other antibiotics ranged from 17.30% to 55.18%. Twenty-four carbapenems-resistant PA strains were screened, including 11 MBL-producing strains and 2 KPC-producing strains. Eleven carbapenems-resistant PA strains were found to harbor the blaVIM-2 gene, accounting for 45.83%; 2 carbapenems-resistant PA strains carried the blaKPC-2 gene, accounting for 8.33%. Fourteen carbapenems-resistant PA strains only harbored the PMQR gene acc (6')-Ib-cr, accounting for 58.33%; 3 carbapenems-resistant PA strains (12.50%) harbored the PMQR genes acc (6')-Ib-cr and qnr, including 1 strain with qnr A1 and 2 strains with qnr B4. Ten carbapenems-resistant PA strains carried the MGE gene ISCR1, accounting for 41.67%; 6 carbapenems-resistant PA strains carried the MGE gene ISEcp1, accounting for 25.00%. In addition, 3 carbapenems-resistant PA strains co-harbored the MGE genes ISCR1 and ISEcp1 (accounting for 12.50%), while only 1 carbapenems-resistant PA strain co-harbored the MGE genes class 1 integron and ISEcp1, accounting for 4.17%. Twelve out of the 13 carbapenemase gene positive strains carried one or two PMQR gene (s), which was significantly higher than that of the carbapenemase gene negative strains (with only five strains harboring one PMQR gene, P = 0.023). The 24 carbapenems-resistant PA strains were classified into 6 genotypes by the ERIC-PCR. Thirteen strains (accounting for 54.17%), mainly isolated from pus and blood samples, which were collected from burn department, were in genotype A. Eight out of the 13 strains harbored genes blaVIM-2, acc (6')-Ib-cr, and ISCR1. Five strains (accounting for 20.83%), mainly isolated from sputum samples which were collected from ICU, were in genotype B. Only 2 out of the 5 strains co-harbored the carbapenemase gene, PMQR gene, and MGE gene. There were respectively 2 strains in genotypes C and D, both accounting for 8.33%; the strains in different pattern were isolated from different wards, and they harbored diverse resistance genes. There were respectively 1 strain in genotypes E and F, both accounting for 4.17%.</p><p><b>CONCLUSIONS</b>The resistance mechanism of PA to carbapenems is mainly mediated by the VIM-2 type MBL in our hospital during 2012, followed by KPC-2 type carbapenemase, and the prevalent genotype is type A. The carbapenemase genes and PMQR genes co-carrying phenomenon exists among these strains of PA, which disseminated by clones.</p>
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Humans , Anti-Bacterial Agents , Pharmacology , Bacterial Proteins , Genetics , Carbapenems , Pharmacology , DNA, Bacterial , Drug Resistance, Bacterial , Microbial Sensitivity Tests , Pseudomonas aeruginosa , Genetics , beta-Lactamases , GeneticsABSTRACT
OBJECTIVE To explore the characteristic of nosocomial infection and formulate the effective measures of nosocomial infection management. METHODS According to the underlying disease condition and method ICD10,the infection data were to classifed and colleced which including of 160 795 cases during 2003-2006.Then the prospective and retrospective investigation were done for studying the nosocomial infection condition. RESULTS The nosocomial infection rate was 4.69%. The highest infection rate was caused by hematological disease (15.43%). By site of infection the upper respiratory infection rate was 35.34%,the lower respiratory infection rate was 28.22%,the gastrointestinal infection rate was 6.82%,and the intra-abdominal infection was 3.75%. In these infection cases,G-bacteria infection occupied 58.35% (which ranked No.1 in all pathogens),and the fungal infection occupied 17.09%. CONCLUSIONS In order to reduce the infection rate,we must enhance the work of preventing the key diseases,standard the measures of disinfection and isolation,increaseing the quarantine inspection rate and applying antibiotic according to the results of antifugal susceptibility testing.
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OBJECTIVE To realize the situation of nosocomial infection and usage of antibiotic in order to prevent and control nosocomial infection effectively. METHODS According to the request of countrywide nosocomial infection net,using the method of clinic investigation and case history investigation,we have investigated the infection complexion about all patients in 19 May 2006 and 24 May 2007,including the duration,transferring department and dead case.Then to analyze the comparison between two results. RESULTS 3489 cases were investigated,including 186 infection cases.The prevalence rate of nosocomial infection was 5.33%.Five departments had the high prevalence rate of nosocomial infection.They were hematology department,ICU,pediatrics department,neonatal unit and cadre ward.The highest rate was 31.30%.The lowest was 0.The infection site focused on lower respiratory tract.The antibiotic utilizing rate was high. CONCLUSIONS Enhanceing the management of nosocomial infection in key departments,regulating the antibiotic utilizing,to reduce the prevalence rate of nosocomial infection.
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OBJECTIVE The research aimed to investigate the incidence,clinical characteristics and risk factors of nosocomial infection in patients with mechanical ventilation in ICU,and explore the corresponding prevention procedures.METHODS Active surveillance was carried out by professional fulltime staff.The patients with mechanical ventilation in ICU above 48 hours were selected for the hospital infection surveillance,and the patients after tracheal intubation within 48 hours were also included.RESULTS The incidence of nosocomial infection was 54.28%,and the nosocomial infection were found in 69(65.71%) of the 105 cases.The major complication was mechanical ventilator-associated pneumonia(VAP).The risk factors were more than four times invasive operation and,tracheotomy(P
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OBJECTIVE To investigate the resistant mechanisms of Candida albicans to azoles at molecular level.METHODS NCCLS M-27 protocols were used to test the in vitro susceptibilities of 102 C.albicans strains isolated from the patients with recurrent vulvovaginal candidiasis(RVVC) against fluconazole(FLC) and itraconazole(ITC) to screen the FLC-and ITC-resistant C.albicans isolates;six pairs of primers,A1-A2,B1-B2,C1-C2,D1-D2,E1-E2 and F1-F2 were respectively to amplify gene CYP51 of 4 strains with FLC-and ITC-resistance.The PCR products were sequenced and analyzed to identify the mutation sites by compared with the sequence of gene CYP51 of referenced C.albicans strain in NCBI site of Internet.RESULTS The analysis of full length sequence of CYP51 from 4 FLC-and ITC-resistant strains showed that from total 32 mutation sites there were 4 significant site mutations,where the mutation of GAT to GAC at 116 caused the substitution of D by E(E266D in two strains);GCC to GGT at 117 caused the substitution of A by G(A117G in 1 strain);GAA to GAC at 266 caused the substitution of E by D(E266D in 2 strains);and GTT to ATT at 488 caused the substitution of I by V(V488I in 1 strain).The site mutations of 266 and 488 were tested in 1 strain of 4 strains.CONCLUSIONS The CYP51 total gene of 4 strains has been checked out.Of FLC and ITC-resistant C.albicans alignment in this time,find out 4 significant bp mutations.Causing its amino acide change,among them,A117G has not be interrelated report still now.The details of mechanism need to be further studied.