Clonal dissemination of fluconazole-resistant Candida albicans strains isolated from vulvovaginal candidiasis / 中国感染与化疗杂志

Objective To investigate the distribution and molecular epidemiology of Candida strains isolated from vulvovaginal candidiasis in Shanghai,and conduct molecular phylogenetic analysis of the strains.Methods Candida pathogens were collected from the patients with vulvovaginal candidiasis during the period from August 2015 to February 2016 in Obstetrics and Gynecology Hospital of Fudan University,Shanghai First Maternity and Infant Hospital,and Intemational Peace Matemity and Child Health Hospital.All the strains were identified and statistically analyzed.ATB FUNGUS 3 kit was used to determine the minimum inhibitory concentration of antifungal agents against these strains in vitro.Molecular typing was conducted using multilocus sequence typing (MLST) method.Phylogenetic analysis was carried out by eBURST and MEGA 6 software.Results Of the 2 185 strains of Candida,1 988 were identified as Candida albicans,149 Candida glabrata,20 Candida tropicalis and 28 other Candida species.Overall,6.5％ of the Candida albicans strains were resistant to fluconazole.Twenty-six diploid sequence types (DSTs) were identified among the 93 strains of Candida albicans analyzed,including 50 fluconazole-susceptible strains with sporadic genotypes,but 43 fluconazole-resistant strains clustered as one clonal complex (CC 69) on the same branch (MLST Clade 1) of phylogenetic tree.Conclusions Candida albicans was the main pathogen of vulvovaginal candidiasis in the three obstetrics & gynecology hospitals in Shanghai,which showed slightly higher resistance to fluconazole.It is necessary to monitor the spread of fluconazole-resistant Candida albicans in these hospitals,especially clonal dissemination of CC 69 clone.

Detection of integrons and ISCR1 in and genotyping of NDM-1-producing Citrobacter freundii / 中国感染与化疗杂志

Objective To investigate the distribution of integrons and ISCR1 elements in NDM-l-producing Citrobacterfreundii isolates,and analyze the genotypes of these strains to understand their homology.Methods A total of 18 strains of NDM-1-producing Citrobacterfreundii were collected from the First Affiliated Hospital of Kunming Medical University during the period from June 2012 and October 2014.The isolates were identified and subjected to antimicrobial susceptibility testing with VITEK 2 System.Class Ⅰ,Ⅱ,and 1Ⅲ integrons and ISCR1 elements were detected by PCR.Clonal relatedness was assessed by pulsed field gel electrophoresis (PFGE).Results Most (77.8％,14/18) strains were positive for class Ⅰ integron conserved region,27.8％ (5/18) isolates were positive for ISCR1 conserved region.No class Ⅱ or Ⅲ integron was detected.Most (72.2％,13/18) isolates were positive for class Ⅰ integron variable region.None of the strains harbored class Ⅱ integron or ISCR1 variable region.Integron variable regions included gene cassette encoding resistance to aminoglycosides (aadA1,aadA5,aac(6')-Ib-cr) and trimethoprim-sulfamethoxazole (dfrA,dfrA15,dfrA17).PFGE revealed 17 clusters among 18 NDM-l-producing Citrobacter freundii isolates.Conclusions The clonal dissemination of NDM-l-producing Citrobacterfreundii isolates is not significant.Class I integron is prevalent in NDM-l-producing Citrobacter freundii.The presence of ISCR1 is relatively rare.The two mobile elements are not related to the spread of NDM-1 gene in this hospital.

Application of RAPD-PCR for Determining the Clonality of Methicillin Resistant Staphylococcus aureus Isolated from Different Hospitals

Randomly amplified polymorphic DNA (RAPD)-PCR was applied with ten random 10-mer primers to examine the molecular diversity among methicillin resistant Staphylococcus aureus (MRSA) strains in the hospitals and to investigate the epidemiological spread of these strains between different hospitals. The main objective of the study was to identify appropriate primers, which successfully established the clonality of MRSA. Three of the primers yielded particularly discriminatory patterns and they were used to perform the RAPD analysis which revealed different bands ranging from 200 to 1500 bp. Dendogram was created by the un-weighted pair group method using arithmetic (UPGMA) average clustering and it was constructed based on the combination results of the new primers (S224, S232 and S395) which represented a novel approach for rapid screening of the strains and also provided the opportunity for monitoring the emergence and determining clonal dissemination of MRSA strains between the hospitals. Dendogram generated two main groups (Group I and II) with three clusters (A, B and C) and indicated that the strains isolated from the same hospital were closely related and they placed together in the same group. This technique could be of attractive use in controlling the sources and routes of transmission, tracking the spread of strains within hospital and between the hospitals, and especially preventing the nosocomial infections caused by the MRSA.

Caracterización molecular de Pseudomonas aeruginosa resistentes a carbapenémicos provenientes de cuatro hospitales de Venezuela / Molecular characterization of carbapenem-resistant Pseudomonas aeruginosa from four hospitals of Venezuela

We analyzed 17 strains of Pseudomonas aeruginosa resistant to carbapenems isolated in four hospitals in eastern and southern Venezuela collected between 2007 and 2010. Combined disk method showed production of metallo־β־lactamases (MBLs) in all strains. PCR and sequencing of genes encoding IMP, VIM and SPM metallo־β־lactamase families confirmed the presence of VIM-2 MMBL in all strains. Pulsed field gel electrophoresis classified the strains into three similarity groups. The largest group, group A included 13 strains with over 83% similarity between them and was found in four hospitals. Two strains of Cumana hospital formed the group B and other two the Group C with similitary of 73% and 65% respectively with Group A. These results confirmed that hospitals in eastern and southern Venezuela, circulating strains of P. aeruginosa producing VIM-2 type MBLs with a common clonal origin. On the other hand, carbapenem-resistant P. aeruginosa circulating in Cumana city hospital had polyclonal origin.

Se analizaron 17 cepas de Pseudomonas aeruginosa resistentes a carbapenémicos aisladas en cuatro hospitales del oriente y sur de Venezuela colectadas entre los años 2007 y 2010. En todas las cepas se demostró la producción de metalo-β-lactamasas (MBLs) por el método de discos combinados. Mediante la amplificación por la reacción de polimerasa en cadena (RPC) de los genes que codifican para las metalo-β-lactamasas de las familias IMP, VIM y SPM, y su posterior secuenciación, se confirmó la presencia de MBLs de tipo VIM-2 en todas las cepas. Mediante la electroforesis de campos pulsantes (ECP), las cepas se clasificaron en tres grupos de similaridad. El grupo dominante (A) estuvo constituido por 13 cepas provenientes de los cuatro hospitales, con similaridad superior al 83% entre ellas. Dos cepas del hospital de Cumaná conformaron el Grupo B y otras dos el Grupo C con similaridad de 73 y 65%, respectivamente, con el Grupo A. Estos resultados confirmaron que en los hospitales del oriente y sur de Venezuela, circulan cepas de P. aeruginosa productoras de MBLs de tipo VIM-2, con un origen clonal común. Asimismo, en el hospital de Cumaná circulan cepas de origen policlonal.

Molecular characterization of clinical multiresistant isolates of Acinetobacter sp. from hospitals in Porto Alegre, State of Rio Grande do Sul, Brazil / Caracterização molecular de isolados clínicos Acinetobacter sp. multirresistentes em hospitais de Porto Alegre, Estado do Rio Grande do Sul, Brasil

INTRODUCTION: Hospitals around the world have presented multiresistant Acinetobacter sp. outbreaks. The spread of these isolates that harbor an increasing variety of resistance genes makes the treatment of these infections and their control within the hospital environment more difficult. This study aimed to evaluate the occurrence and dissemination of Acinetobacter sp. multiresistant isolates and to identify acquired resistance genes. METHODS: We analyzed 274 clinical isolates of Acinetobacter sp. from five hospitals in Porto Alegre, RS, Brazil. We evaluated the susceptibility to antimicrobial, acquired resistance genes from Ambler's classes B and D, and performed molecular typing of the isolates using enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) technique. RESULTS: A high (68 percent) percentage of multiresistant isolates of Acinetobacter sp. was observed, and 69 percent were resistant to carbapenems. We identified 84 percent of isolates belonging to species A. baumannii because they presented the gene blaOXA-51. The gene blaOXA-23 was detected in 62 percent of the isolates, and among these, 98 percent were resistant to carbapenems. Using the ERIC-PCR technique, we identified clones of Acinetobacter sp. spread among the four hospitals analyzed during the sampling period. CONCLUSIONS: The data indicate the dissemination of Acinetobacter sp. isolates among hospitals and their permanence in the hospital after one year.

INTRODUÇÃO: Hospitais no mundo todo têm apresentado surtos de Acinetobacter sp. multirresistentes. A disseminação destes isolados com uma variedade cada vez maior de genes de resistência torna difícil o tratamento destas infecções e seu controle dentro do ambiente hospitalar. Este trabalho teve como objetivo avaliar a ocorrência e disseminação de isolados de Acinetobacter sp. multirresistentes e identificar genes de resistência adquirida. MÉTODOS: Foram avaliados 274 isolados clínicos de Acinetobacter sp. obtidos de cinco hospitais da Cidade de Porto Alegre, RS, Brasil. Avaliamos o perfil de suscetibilidade a antimicrobianos, genes de resistência adquirida das classes B e D de Ambler e realizamos a tipificação molecular dos isolados utilizando a técnica de enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR). RESULTADOS: Encontramos uma alta (68 por cento) porcentagem de isolados de Acinetobacter sp. multirresistentes e 69 por cento dos isolados apresentaram resistência aos carbapenêmicos. Foram identificados 84 por cento de isolados pertencentes a espécie A. baumannii, pois apresentaram o gene blaOXA-51. Em 62 por cento dos isolados, foi detectado o gene blaOXA-23, sendo que 98 por cento destes isolados foram resistentes aos carbapenêmicos. Através da tipificação molecular pela técnica de ERIC-PCR identificamos clones de Acinetobacter sp. disseminados entre quatro dos hospitais analisados e nos anos de 2006 e 2007. CONCLUSÕES: Os dados obtidos indicam a disseminação de isolados de Acinetobacter sp. entre hospitais assim como sua permanência no ambiente hospitalar após um ano.

Genotipificación de cepas de enterobacterias procedentes de 4 centros de salud del área de Caracas / Genotyping of enterobacterias strains from 4 healthcare centers in Caracas

Las infecciones nosocomiales pueden ser producidas por microorganismos resistentes a la acción de los antimicrobianos que han sido seleccionados por la mal uso ó el uso indiscriminado de los antibióticos en el ámbito hospitalario. En los últimos años se han desarrollado nuevas técnicas moleculares de tipificación basada en la reacción en cadena de la polimerasa (PCR), que han representado un avance importante en el estudio de las enfermedades infecciosas, siendo muy útiles al permitir diferenciar serotipos estrechamente relacionados y grupos de cepas no relacionadas clonalmente, debido a su gran poder discriminatorio. En Venezuela, son pocos los estudios de eepidemiología molecular de las infecciones intrahospitalarias, y por esta razón nos propusimos genotipificar cepas de Escherichia coli y Klebsiella pneumoniae provenientes de aislados nosocomiales de cuatro centros de salud del área metropolitana (Hospital "Dr. José María Vargas", Hospital "Dr. Domingo Luciani", Centro Médico de Caracas y Policlínica Metropolitana) con la finalidad de determinar la relación clonal existente entre estas cepas. El uso de ERIC-PCR permitió relacionar parcialmente las especies de E. coli aisladas en los cuatro centros de salud, sin embargo la técnica de REP-PCR permitió discriminar entre los patrones de bandas similares, mostrando un poder de resolución mayor. El uso de ERIC-PCR y REP-PCR no permitió tipificar la mayoría de las cepas de K. pneumoniae aisladas en los cuatro centros de salud en estudio. En el Centro Médico de Caracas se identificaron dos aislados clonales provenientes de diferentes áreas del hospital, Unidad de Terapia de Adultos y Hospitalización. En la Policlínica Metropolitana se identificaron tres aislados clonales, dos en la unidad de Terapia y uno en Hospitalización. En el Hospital "Dr. Domingo Luciani" y en el Hospital "Dr. José María Vargas" no se identificaron clones. Estos resultados proporcionan un aporte a los programas de vigilancia...

Nosocomial infections can be produced by microorganisms resistand to antimicrobial agents, and they have been selected by the bad use or abuse of antibiotics in the hospital environment. Recently, new molecular typing techniques have been developed, based on polymerase chain reaction (PCR). These techniques represent an important advantage the study of infectious diseases; they are able to discriminate relate closed serovars and groups of nonrelated isolates due to its great power discriminatory. In Venezuela, there is a small number of molecular epidemiology researches. The goal of the present study is genotyping Escherichia coli and Klebsiella pneumoniae isolated of nosocomial infected patients from four healthcare centers in the metropolitan area (Hospital "Dr. José María Vargas", Hospital "Dr. Domingo Luciani", Centro Médico de Caracas, Policlínica Metropolitana) in order to investigate the clonal relationship between the isolates. ERIC-PCR allowed us to correlate E. coli isolates however REP-PCR shows greater greater resolution. The use of both ERIC-PCR and REP-PCR, did not permit us typing K. pneumoniae isolates. Two clonally related isolates from Centro Médico de Caracas were identified. Three clonally related isolates from the Policlínica Metropolitana ere identified. No clones were identified in samples from Hospital "Dr. Domingo Luciani" and the Hospital "José María Vargas". These results contribute to monitoring programs, to improve the control of the bacterial infections, helping to establish efficient procedures and reduce nosocomials infections.