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Objective To investigate molecular epidemiology and antimicrobial susceptibility of carbapenem-resistant strains of Klebsiella pneumoniae isolated from children.Methods From July 2010 to June 2011,twelve non-replicate clinical isolates of carbapenem-resistant Klebsiella pneumoniae were consecutively collected from children inpatients in the Second Hospital of Wenzhou Medical Colloge.All of the isolates were identified by the automated microbiology systems.Modified Hodge test was used to screen strains producing carbapenemases.Pulsed field gel electrophoresis(PFGE) was performed to analyze the homogeneity of genomic DNA of Klebsiella pneumoniae.KPC,IMP,GIM,SPM,SME,OXA-10,bla(s),VIM gene and integrase gene were amplified by PCR and then sequenced to cofirm the genotypes;Plasmid conjugation experiment was used to study the transfer method of bacterial resistance.Plasmid-curing test were used to initally locate the resistant genes.Results One(8.3％),5(41.7％),7(58.3％),1(8.3％),1(8.3％) and4(33.3％) of12isolates were susceptible to gentamicin,tobramycin,amikacin,ciprofloxacin,levofloxacin and trimoxazole,respectively.All isolates carried KPC-2,TEM-1 and SHV genes(six for SHV-11-like,six for SHV-12-like).Eleven of twelve isolates with KPC-2 gene carried CTX-M genes(4 for CTX-M-14-like,6 for CTX-M-15-like).Two isolates carried OXA-10 genes,and one isolates carried PER-1 gene.None of NDM-1,GIM,SPM,SIM and VIM carbapenemase genes was detected in 12 isolates.All of 12 isolates carried Int 1 genes.The plasmids of 2 isolates were transgerred into the recipients E.coli EC600.PCR and sequence analysis revealed that blaTEM-1 and blaCTX-M-15-like were co-transferred with the KPC-2 gene to the recipients.Elimination of KPC-2-encoding plasmid from Kp7 and Kp12 resulted in imipenem susceptibility in the two isolates.Amplification revealed that KPC-2 gene was lost by the plasmid-curing test.Of the 12 isolates,5 patterns were obtained by PFGE.Pattern B and C were the main drug resistant clones.Conclusion KPC-2 gene are the major carbapenemase genes in Klebsiella pneumoniae isolated from children,including ESBLs and integrase.Some resistance genes can be disseminated by plasmids.
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ObjectiveTo investigate the prevalence and distribution of 16S rRNA methylase gene and research the relationship with drug resistant spectrum.And preliminary explore its role in molecular epidemiology analysis.MethodsCollected 69 clinical isolates of non repetitive ESBL-producing Klebsiella pneumoniae in our hospital from Mar to Sep 2010.Detection 16S rRNA methylation enzyme gene by PCR,and analyze ESBL genetype and integron gene of the positive strains.All PCR products were sequenced for determination.Plasmid conjugation test and plasmid elimination method to determine dissemination of 16S rRNA methylase gene.Then we used ERIC-PCR genotyping technology for the establishment of DNA fingerprinting.ResultsIn sixty-nine strains,twenty isolates were rmtB positive (28.9％),two isolates were armA positive,and two strains coproduce rmtB and armA.All positive isolates carried the CTX-M gene,detemined by sequencing,14 strains of CTX-M-14 gene,6 strains of CTX-M-15 gene,14 strains carried TEM1 gene,8 strains carried SHY gene,sequencing showed that 5 strains of SHV-12 gene,3 strains of SHV-11 gene,3 strains carried OXA-10 gene,3 strains carried VBE-1 gene.In addition,the intl gene was found in 12 isolates of 20 rmtB positive strains.All the intl gene positive strains were divided into five kinds gene cassettes,which contained drfA25,drfA1,drfA12,aadA1,aadA2,sat and blaVEB-1 genes.Respectivily,16S rRNA methylase gene positive strains were divided into five genetypes using ERIC-PCR technology.A genetype was the advantage popular clones.Conjugative plasmid and elimination test found that rmtB gene was located in a plasmid in KP5 and KP16 isolates with A genetype,and can disseminate by conjugation.ConclusionA high prevalence of 16S rRNA methylase gene-rmtB was found among clinical ESBL-producing K.pneumoniae isolates in our hospital,which could lead to resistant to almost all aminoglycoside at a high level.Both horizontal gene transfer and clonal spread were responsible for the dissemination of the rmtB gene.In addition,K.pneumoniae co-producing ESBLs,16S rRNA methylation enzymes and class Ⅰ integron existed and were spreading.
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OBJECTIVE To study the homology of the pandrug-resistant Acinetobactor baumannii(PRABA) by randomly amplificed polymorphic DNA(CRPD) to guide the control of the nosocomial infection and epidemology investigation.METHODS Eighteen strains of PRABA were collected from Jul 2008 to Mar 2009 in our hospital.The bacteria were examined by DADE BEHRING Microscan WalkAway 96SI;DNA extracted from all isolates was amplified by polymerase chain reaction using random primers.In addition epidemology investigation and antimicrobial susceptibility testing were also under taken.RESULTS Fifteen strains were divided into 6 RAPD profiles.There were two clonal strains derived,respectively,from two intensive care units.One strain was isolated from a patient in surgical ward who was transferred from ICU1,showing same homology with that in the ICU1.The homology was different from sensitive strains and drug-resistant strains obviously.CONCLUSIONS An outbreak of PRABA happens in intensive care unit.
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OBJECTIVE To analyze the profile of the pathogens and their drug resistance isolated from children with lower respiratory tract infection in Wenzhou area from Jan 2004 to Dec 2006.METHODS Lower respiratory tract secretions were obtained from children with lower respiratory tract infection for bacterial culture.The K-B method was applied for the antibiotic susceptibility test.RESULTS Total 1605 strains were isolated.The isolating rates of Gram-positive cocci,Gram-negative bacilli and fungi were 24.9%,61.2% and 14.0%,respectively.60.5%,and 54.6% of the isolates of Escherichia coli and Klebsiella pneumoniae produced extended-spectrum beta-lactamases(ESBLs).The rate of Penicillin-resistant Streptococcus pnenmoniae(PRSPN)was 30.6%.20.5% isolates of Staphylococcus aureus were MRSA.All isolates of Enterobacteriaceae and Gram-positive cocci were susceptible to imipenem and vancomycin in vitro.CONCLUSIONS Gram-negative bacilli are still the primary pathogens resulting in lower respiratory tract infection in children.Fungi and muti-drug-resistant bacteria are on the rise trend.
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<p><b>OBJECTIVE</b>To improve the clinician's awareness of angiostrongyliasis.</p><p><b>METHODS</b>The clinical and laboratory data as well as the epidemiological information concerning 18 patients with eosinophilic meningoencephalitis caused by Angiostrongylus cantonensis were analyzed.</p><p><b>RESULTS</b>All patients had a history of eating raw fresh water snail (Ampularium canaliculatus) before the onset of the disease. Incubation period ranged from 1 to 25 days. The major symptoms of the patients had severe headache and pain in the trunk and limbs. Increased eosinophlic count in peripheral blood and cerebrospinal fluid was noted. Tested by enzyme-linked immunoadsorbent assay (ELISA), sera were specifically IgG-antibody positive against Angiostrougylus cantonensis antigen, but were negative against other parasitic antigens such as Paragonimus westermani, Cysticerus, Cellulosae hominis, Echinococcus granulosus and Trichinella spiralis. Abnormal spotty signals were found in 2 cases with brain magnetic resonance imaging. Electroencephalogram (EEG) showed slow alpha rhythm. All the patients were effectively treated with combined administration of albendazole and dexamethazone.</p><p><b>CONCLUSIONS</b>Angiostrongyliasis is one of the common causes leading to eosinophilic meningoencephalitis. To our knowledge, Wenzhou is the first small outbreak site of angiostrongyliasis discovered in Chinese mainland.</p>
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Adult , Animals , Female , Humans , Male , Middle Aged , Albendazole , Angiostrongylus cantonensis , Dexamethasone , Eosinophilia , Meningoencephalitis , Prognosis , Strongylida Infections , Drug TherapyABSTRACT
OBJECTIVE To investigate the function of CHROMagar orientation medium for quick detection of(urinary) tract pathogens.METHODS The comparative experiment was performed with CHROMagar orientation(medium) and 5% sheep blood agar for clinical urine specimens from the patient with suspective urinary tract(infections).RESULTS Among the total of 1369 clinical urine specimens,1023 specimens yielded no growth,344 specimens yielded growth on both media,and 2 other specimens yielded no growth on blood agar but yielded growth on CHROMagar orientation medium.CONCLUSIONS The growth of bacteria is not inhibited by the(orientation) medium and no significant differences were found in the results between the both media.The(orientation) medium can quickly confirm the genus of the pathogens,and it has significance for using antibiotics(reasonably).One of the greatest advantages of this medium is the easy recognition of mixed cultures.