Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 38
Filtrar
1.
Mikrobiyol Bul ; 58(2): 97-112, 2024 Apr.
Artigo em Turco | MEDLINE | ID: mdl-38676579

RESUMO

The aim of the study was to evaluate the relationship between carbapenem-resistant Acinetobacter baumannii isolates carrying oxacillinase-type carbapenemase genes with "international high-risk clones" (IC I, II, and III) by different molecular epidemiological methods and to statistically compare the concordance and discrimination power of the methods. Carbapenem-resistant and moderately susceptible A.baumannii isolates from non-repeating blood cultures of 72 patients were included in the study. The presence of "blaOXA-23 , blaOXA-24 , blaOXA-51 ve blaOXA-58 " genes within OXA-type carbapenemases was detected by polymerase chain reaction (PCR) method and confirmed by DNA sequence analysis. Pulsed f ield gel electrophoresis (PFGE), multilocus sequence typing (MLST) and matrix-assisted laser desorption/ ionization time- of-flight mass spectrometry (MALDI-TOF MS) analyses were performed to evaluate the clonal relations of IC I, II and III clones together with clinical isolates. In the statistical comparison of the methods, discrimination power was evaluated by Simpson index of diversity (SID) and concordance by "Wallace coefficient". All of the isolates were found to carry blaOXA-23 and blaOXA-51 genes. As a result of the bioinformatic analysis of the four isolates selected for sequence analysis; blaOXA-23 and blaOXA-51 genes were detected in the selected isolates, and the analysis of two isolates carrying blaOXA-51 gene showed 99% similarity with blaOXA-92 gene. The isolates were clustered into five pulsotypes (A, B, C, D and E) according to ≥ 85% similarity coefficient by PFGE. The isolates and RUH 875, RUH 134, LUH 5875 strains belonging to high-risk clones ICI, ICII and ICIII, respectively, were divided into five main groups [A (n= 58), B (n= 8), C (n= 4), D (n= 4) and E (n= 1)] and 10 subgroups (A1, A2, A4, A5, A6, A9, B1, B4, C3, D1) by PFGE. IC clone III (E1) and seven strains showed singleton PFGE profiles (A3, A7, A8, B2, B3, C1, C2). ICII was found in A5 subtype, ICI in C1 subtype and ICIII in E1 subtype. By PFGE subtype groups, 18 pulsotypes were determined and ST1, ST2, ST81, ST157 and ST604 sequence types were found in 20 isolates randomly selected from pulsotypes according to MLST Pasteur scheme (cpn60, fusA, gltA, pyrG, recA, rplB, rpoB). Principal component analysis (PCA) of the spectra of 72 A. baumannii isolates and ICI, ICII and ICIII clones was performed by MALDI-TOF MS. In PCA analysis, the cluster distance level was defined as 1.5 and the isolates were divided into three clusters. IC clone I, II and III together with 70 clinical isolates were grouped in one cluster, while two clinical isolates (AB083 and AB0115) formed singleton clusters. There was no significant agreement between MALDI-TOF MS; MLST and PFGE data according to Wallace coefficient. It was found that PFGE method gave significant results in terms of discrimination power with SID coefficient, MALDI-TOF MS PCA analysis had the lowest discrimination power value, and the Wallace coefficient result of PFGE and MLST was concordant. In conclusion, MALDI-TOF MS may not function as a gold standard method like PFGE and MLST for epidemiological analysis in A.baumannii species and the epidemiological typing protocols used for MALDI-TOF MS need to be improved and developed.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , Carbapenêmicos , Eletroforese em Gel de Campo Pulsado , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , beta-Lactamases , Humanos , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/genética , Acinetobacter baumannii/classificação , Acinetobacter baumannii/isolamento & purificação , Carbapenêmicos/farmacologia , Infecções por Acinetobacter/epidemiologia , Infecções por Acinetobacter/microbiologia , beta-Lactamases/genética , Proteínas de Bactérias/genética , Reação em Cadeia da Polimerase
2.
Ann Med ; 55(1): 266-275, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-36579976

RESUMO

OBJECTIVE: To evaluate the serotype distribution and antibiotic resistance in pneumococcal infections in adults and to provide a perspective regarding serotype coverage of both current and future pneumococcal vaccines. PATIENTS AND METHODS: This passive surveillance study was conducted with the Streptococcus pneumoniae strains isolated from the specimens of patients with pneumonia (materials isolated from bronchoalveolar lavage), bacteraemia, meningitis, pleuritis and peritonitis between 2015 and 2018. Serogrouping and serotyping were performed by latex particle agglutination and by conventional Quellung reaction using commercial type-specific antisera, respectively. The strains were analysed for penicillin, cefotaxime, erythromycin and moxifloxacin susceptibilities by E-test. RESULTS: In the whole study group (410 samples from adults aged ≥18 years), the most frequent serotypes were 3 (14.1%), 19 F (12%) and 1 (9.3%). The vaccine coverage for PCV13, PCV15, PCV20 and PPV23 was 63.9%, 66.6%, 74.1% and 75.9%, respectively, in all isolates. Penicillin non-susceptibility in invasive pneumococcal disease (IPD) was 70.8% and 57.1% in the patients aged <65 and ≥65 years, respectively. About 21.1% and 4.3% of the patients with and without IPD had cefotaxime resistance. Non-susceptibility to erythromycin and moxifloxacin was 38.2% and 1.2%, respectively. CONCLUSIONS: The results revealed that novel PCV vaccines may provide improved coverage as compared with the currently available vaccine, PCV13. The significant antibiotic resistance rates imply the need to extend the serotype coverage of the vaccines. Continuing the surveillance in pneumococcal diseases is critical to explore the serotype distribution and incidence changes of IPD cases in the population and to inform policy makers to make necessary improvements in the national immunization programmes.Key messagesThis multicentre study demonstrated the most recent serotype distribution and antibiotic resistance in adult population in Turkey.Shifting from PCV13 to novel conjugated vaccines will significantly increase the coverage.Continuing the surveillance in pneumococcal diseases is critical to explore the serotype distribution changes and the incidence of cases with invasive pneumococcal disease in the population.


Assuntos
Infecções Pneumocócicas , Streptococcus pneumoniae , Adulto , Humanos , Lactente , Adolescente , Sorogrupo , Vacinas Pneumocócicas , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Moxifloxacina , Turquia/epidemiologia , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/prevenção & controle , Infecções Pneumocócicas/tratamento farmacológico , Cefotaxima/farmacologia , Cefotaxima/uso terapêutico , Eritromicina , Penicilinas/farmacologia , Penicilinas/uso terapêutico
3.
J Matern Fetal Neonatal Med ; 33(21): 3658-3665, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30760078

RESUMO

Objective: Neonatal sepsis, especially nosocomial sepsis (NS) is one of the main causes of mortality and morbidity in neonates. Our aim was to investigate microorganisms responsible for NS and antimicrobial susceptibility patterns and to compare them in a different period.Methods: Blood culture registers from the Microbiology Laboratory were reviewed for the study population. The neonates with proven NS were enrolled in the study. Microorganisms responsible for NS and antimicrobial susceptibility patterns were recordedResults: The incidence of Gram-positive, Gram-negative, and fungal microorganisms were 61.6% (n = 570), 27.1% (n = 251) and 11.3% (n = 104), respectively. The most common isolated Gram-positive, Gram-negative pathogens and fungi were Coagulase-negative staphylococci (CoNS), Klebsiella pneumoniae, and C. guilliermondii. There was an increasing resistance rate among common nosocomial pathogens especially oxacillin resistant CoNS strains and increasing rate for extended-spectrum beta-lactamase (ESBL) positive microorganisms. Low susceptibility was detected to commonly used antibiotics for empirical treatment in neonatal sepsis.Conclusions: Our result showed that multiresistant microorganisms, especially oxacillin-resistant staphylococci and gram-negative bacilli resistant to cephalosporin have an increasing rate. Every unit should evaluate the causative agents and antimicrobial susceptibilities in order to select an appropriate regime for nosocomial sepsis. Periodic surveillance of organisms and their antibiotic resistance patterns in every unit might help physicians for proper selection of antibiotics for treatment of neonatal NS.


Assuntos
Infecção Hospitalar , Sepse Neonatal , Sepse , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/epidemiologia , Resistência Microbiana a Medicamentos , Humanos , Recém-Nascido , Testes de Sensibilidade Microbiana , Sepse Neonatal/tratamento farmacológico , Sepse/tratamento farmacológico
4.
Indian J Med Microbiol ; 36(2): 257-264, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30084421

RESUMO

Background: Reservoir of methicillin resistance genes called staphylococcal cassette chromosome mec (SCCmec), plasmids and genomic characterisations of isolates have been widely investigated in epidemiologic research. However, the extent to which these organisms are transported by patients or hospital staff is not entirely clear. Aim: This study aims to investigate the molecular relatedness and plasmid profiles of MR staphylococci isolated from nursing students before and after hospital training, to find out the possible source. Materials and Methods: This study examined 39 methicillin-resistant (MR) staphylococci and 2 inducible clindamycin-resistant, methicillin-susceptible Staphylococcus aureus. Specimens were collected before and after 4 months of hospital training from the hands and nares of 75 nursing students. A polymerase chain reaction technique was used to confirm the existence of mecA gene and identify SCCmec types; total DNA was digested by SmaI endonuclease restriction to monitorise clonal relatedness by pulsed-field gel electrophoresis (PFGE); plasmid profiles were monitorised on agarose gel. Results: All 39 isolates tested positive for mecA; SCCmec type III was observed most frequently. Interestingly, in one isolate of Staphylococcus epidermidis, four different types of SCCmec elements were observed. There were 23 different types of plasmids, whose sizes ranged from 1.4 to 46.0 kb. After PFGE dendogram analysis, two strains were classified as indistinguishable; six were closely related. Most of the isolates obtained after hospital training showed clonal similarity and seven had multiple SCCmec elements require further investigation for the possible mechanism. Conclusion: Most of the isolates obtained after hospital training showed clonal similarity and seven had multiple SCCmec elements require further investigation for the possible mechanism.


Assuntos
Staphylococcus aureus Resistente à Meticilina/genética , Antibacterianos/farmacologia , Eletroforese em Gel de Campo Pulsado , Genótipo , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Plasmídeos/genética , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus epidermidis/genética
5.
Pediatr Neonatol ; 59(3): 305-309, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29150336

RESUMO

BACKGROUND: It is controversial to test for urinary tract infection (UTI) in patients with unexplained indirect hyperbilirubinemia in the first 2 weeks of life. We aimed to study the prevalence and significance of UTIs in such neonates who were requiring phototherapy. METHODS: Subjects were 2- to 14-day-old neonates with indirect bilirubin levels above phototherapy limit with no other abnormality in their bilirubinaemia-related etiologic workup. UTI was diagnosed by 2 consecutive positive cultures obtained by catheterisation, documenting growth of >10,000 colonies of the same microorganism with consistent antibiograms. The UTI (+) patients were evaluated by renal ultrasonography (US), and some were followed up for possible recurrent UTI. RESULTS: 262 neonates were included in the study. UTI prevalence was 12.2%, and bacteraemia was 6.2% among UTI (+) patients. The two most common pathogens (81.2%) were Escherichiacoli and Klebsiella. pneumonia. All UTI (+) patients had undergone US, revealing 12.5% pelvicaliectasis, other 12.5% increased renal parenchymal echogenicity, 3.1% concurrent pelvicaliectasis and increased renal parenchymal echogenicity. 53.1% of UTI (+) patients had undergone follow-up, after which 23.5% recurrent UTI were found at the end of a mean of 52 months. CONCLUSION: We suggest that the neonates with unexplained pathological jaundice should be tested for possible UTI. Consequently, all newborns with UTI shall be evaluated by the urinary US and followed up for recurrent UTI.


Assuntos
Hiperbilirrubinemia/etiologia , Infecções Urinárias/epidemiologia , Feminino , Humanos , Recém-Nascido , Icterícia/etiologia , Rim/diagnóstico por imagem , Masculino , Fototerapia , Prevalência , Ultrassonografia , Infecções Urinárias/complicações , Infecções Urinárias/diagnóstico por imagem
6.
Mikrobiyol Bul ; 51(3): 299-303, 2017 Jul.
Artigo em Turco | MEDLINE | ID: mdl-28929967

RESUMO

Colistin is a polymyxin antibiotic which is considered as one of the last line agents against infections due to multidrug resistant or carbapenem resistant gram-negative pathogens. Colistin resistance is associated with chromosomal alterations which can usually cause mutations in genes coding specific two component regulator systems. The first plasmid-mediated colistin resistance gene, mcr-1 was described in Escherichia coli and Klebsiella pneumoniae isolates in December 2015 and followed by another plasmid-mediated colistin resistance gene mcr-2 in 2016. The rapid and interspecies dissemination of plasmid-mediated resistance mechanisms through horizontal gene transfer, have made these genes considerably threatening. After the first reports, although mcr-1/mcr-2 producing Enterobacteriaceae isolates have been reported from many countries, there have been no reports from Turkey. Thus, the aim of this study was to investigate the presence of mcr-1/mcr-2 in clinical Enterobacteriaceae isolates from different parts of our country. A total of 329 Enterobacteriaceae isolates from 22 laboratories were collected which were isolated between March, 2015 and February, 2016. mcr-1/mcr-2 were investigated by polymerase chain reaction during February-March, 2016. Two hundred and seventeen of Klebsiella pneumoniae (66%), 75 of Salmonella spp. (22.8%), 31 of Esherichia coli (9.4%), 3 of Enterobacter cloacae (0.9%), 2 of Klebsiella oxytoca (0.6%) and 1 of Enterobacter aerogenes (0.3%) isolates were included to the study. Agarose gel electrophoresis results of PCR studies have shown expected band sizes for positive control isolates as 309 bp for mcr-1 and 567 bp for mcr-2. However, the presence of mcr-1/mcr-2 genes was not detected among the tested study isolates of Enterobacteriaceae. Although mcr-1/mcr-2 were not detected in our study isolates, it is highly important to understand the mechanism of resistance dissemination and determine the resistant isolates by considering that colistin is a last-line antibiotic against infections of multidrug or carbapenem resistant gram-negative bacteria. Thus, it is suggested that these mechanisms should be followed-up in both clinical and non-clinical (e.g. isolates from food animals, raw meats and environment) isolates of special populations.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Colistina/farmacologia , Farmacorresistência Bacteriana/genética , Enterobacteriaceae/genética , Fatores R , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/isolamento & purificação , Humanos , Turquia
7.
Mikrobiyol Bul ; 50(3): 505-7, 2016 Jul.
Artigo em Turco | MEDLINE | ID: mdl-27525407

RESUMO

The rapid and accurate identification of carbapenemases is of crucial importance in terms of infection control. Methods employed in the determination of carbapenemases should be constantly updated in the light of technical advances and newly emerging carbapenemase variants. The aim of this study was to evaluate the performance of the newly developed carbapenem inactivation method (CIM) for the identification of carbapenemases defined in the members of the family Enterobacteriaceae. Enterobacteriaceae isolates with resistance to at least one of the carbapenems (ertapenem, imipenem or meropenem) were included in the study. The study isolates were obtained from various clinical specimens between 2008-2014 and consisted of 56 Enterobacteriaceae strains (12 Escherichia coli, 32 Klebsiella spp., and 12 Enterobacter spp.) in which the presence of the 38 blaOXA-48, 8 blaVIM, 7 blaIMP, 1 blaNDM-1, 1 blaKPC-2 and 1 blaOXA-48+blaVIM genes had been previously determined using the polymerase chain reaction (PCR) and 78 in which no carbapenemase gene were detected. For the performance of the CIM, the test bacteria were suspended in sterile water and then a 10 µg meropenem disc was immersed in the suspension and incubated for 2 hours. This meropenem disc was then removed and subsequently placed on a Mueller-Hinton agar plate inoculated with E. coli ATCC 29522 and incubated at 35°C. The results were assessed after 6 hours and after overnight incubation. Development of an inhibition zone around the meropenem disk was interpreted as the absence of carbapenemase and the lack of an inhibition zone as the presence of carbapenemase. The results of the CIM were obtained after 8 hours. With the CIM, all isolates with previously determined carbapenemase genes were found to be positive and the isolates with no genes revealed to be negative. The sensitivity and specificity of CIM were estimated as 100%. The high sensitivity and specificity, ease of application and interpretation, rapid production of results, and no necessity for additional equipment or chemical substances, makes CIM a promising high throughput method to be used in routine microbiology laboratories. Since this method indicates only the presence of a carbapenemase in a clinical isolate, the type of the carbapenemase present should be further identified by the use of molecular techniques.


Assuntos
Proteínas de Bactérias/metabolismo , Carbapenêmicos/metabolismo , Enterobacteriaceae/enzimologia , beta-Lactamases/metabolismo , Humanos , Sensibilidade e Especificidade
8.
Mikrobiyol Bul ; 50(2): 186-95, 2016 Apr.
Artigo em Turco | MEDLINE | ID: mdl-27175491

RESUMO

One of the treatment options of Escherichia coli and Klebsiella spp. infections which are the most common opportunistic pathogens of gram-negative sepsis is quinolones. Resistance to quinolones which act by disrupting DNA synthesis has been increasing. Horizontal transfer of plasmid-mediated quinolone resistance (PMQR) genes play an important role in the spread of resistance. The data about the prevalence of PMQR genes in our country is quite limited. The aim of this study was to investigate the presence of known PMQR genes namely qnrA, qnrB, qnrC, qnrS, qnrD, aac(6')-Ib-cr, qepA and oqxAB amongst quinolone-resistant E. coli and Klebsiella spp. strains isolated from blood cultures. One hundred twenty seven E.coli and 66 Klebsiella isolates detected as nalidixic acid- and/or ciprofloxacin-resistant by phenotypical methods, from 193 blood samples of 187 patients admitted to Karadeniz Technical University, Faculty of Medicine, Department of Medical Microbiology, Bacteriology Unit of Patient Service Laboratory between January 2012 to August 2013 were included in the study. The presence of PMQR genes were investigated by polymerase chain reaction (PCR) and for the detection of aac(6')-Ib-cr variants PCR-restriction fragment length polymorphism (PCR-RFLP) method was used. The positive bands were sequenced using the same primers, and aligned with formerly defined resistance gene sequences, and confirmed. In the study, 56.7% (72/127) of E.coli and 19.7% (13/66) of Klebsiella spp. isolates, with a total of 44% (85/193) of all the isolates were found to be phenotypically resistant to quinolones. Of the 13 resistant Klebsiella isolates, 11 were K.pneumoniae, and two were K.oxytoca. Extended-spectrum beta-lactamase (ESBL)-producing isolates showed higher resistance (50/80, 62.5%) to quinolones than the negative ones (35/113, 30.9%). The prevalence of quinolone resistance genes among resistant E. coli and Klebsiella spp. isolates was determined as qnrA, 1.4% and 15.4%; qnrB, 4.2% and 61.5%; qnrS, 1.4% and 7.7%; qepA, 1.4% (only E.coli); aac(6')-1b-cr, 38.9% and 92.3%; and oqxAB, 1.4% and 84.6%, respectively. qnrC and qnrD genes were not detected. Carriage of multiple resistance genes were observed more frequently among resistant Klebsiella isolates than E.coli strains. As a result, in this study investigating the contribution of transferrable genes to quinolone resistance, prevalence of PMQR genes in quinolone-resistant and blood isolates of E.coli and Klebsiella in our university hospital serving the region were found to be higher than the current data reported from the other studies in our country. Furthermore, this study presented the initial data for the first time in our country on the prevalence of qnrD which was undetected, and the frequency of oqxAB gene in clinical samples. However, location of oqxAB gene needs to be confirmed by conjugation or hybridization methods.


Assuntos
Bacteriemia/microbiologia , Infecções por Escherichia coli/microbiologia , Escherichia coli/efeitos dos fármacos , Infecções por Klebsiella/microbiologia , Klebsiella/efeitos dos fármacos , Quinolonas/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Humanos , Klebsiella/genética , Klebsiella/isolamento & purificação , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Fatores R , Alinhamento de Sequência , beta-Lactamases/biossíntese
9.
Mikrobiyol Bul ; 50(1): 1-10, 2016 Jan.
Artigo em Turco | MEDLINE | ID: mdl-27058324

RESUMO

A rapid, practical, and accurate identification of carbapenemase-producing Enterobacteriaceae isolates is crucial for the implementation of appropriate infection control measures and proper treatment of the infections. For this purpose, a large number of phenotypic test methods have been developed, although none has 100% sensitivity and specificity. Variations in sensitivity and specificity of these tests based on the type of beta-lactamase enzymes carried by that isolates might result in differences between regions and countries. The aim of this study was to compare the performances of widely used modified Hodge test (MHT) and Carbapenemase Nordmann-Poirel (Carba NP) test in the detection of carbapenemases in Enterobacteriaceae family members. A total of 65 Enterobacteriaceae isolates (43 bla(OXA-48), 10 bla(VIM), 9 bla(IMP), 1 bla(NDM-1), 1 bla(KPC-2) and 1 bla(OXA-48)+bla(VIM) carrying strains) that showed decreased sensitivity to at least one carbapenem (ertapenem, imipenem or meropenem), and carriage of carbapenemase gene confirmed by polymerase chain reaction (PCR), were included in the study. Seventy-eight isolates showing decreased susceptibility to carbapenems but lacking carbapenemase genes were used as controls. All isolates were identified by using conventional methods as well as automated BD Phoenix System (Becton Dickinson, USA). The antimicrobial susceptibility testing was performed using the same automated system, and was confirmed by disk diffusion method. Results were evaluated according to the CLSI criteria. MHT was performed in accordance with the CLSI guideline, and Carba NP test was carried out by a modified protocol. Instead of imipenem monohydrate, which was used in the original protocol, 6 mg/ml imipenem/cilastatin was used in the modified protocol. In the study, MHT identified 90.8% (59/65) of carbapenemase-producing isolates, while 93.9% (61/65) of the isolates were identified by Carba NP test. With MHT, four Klebsiella pneumoniae producing OXA-48, one Escherichia coli producing IMP, and one K.pneumoniae producing NDM-1, and with Carba NP test, one E.coli and one K.pneumoniae producing OXA-48, one E.coli producing IMP, and one Enterobacter cloacae producing VIM could not de detected. Three OXA-48-producing isolates (two K.pneumoniae and one E.coli) yielded late and weak positive results with Carba NP test. MHT had false positivity for 31 isolates, while Carba NP test showed no false positivity. In comparison of the sensitivity and specificity of the two tests, sensitivities were found to be similar although the Carba NP has a slightly higher sensitivity than the MHT (93.9% versus 90.8%, respectively; p= 0.754), Carba NP was found more specific (100% versus 60.3%, respectively; p< 0.0001). With Carba NP test, 26% of the isolates (n= 16) were positive within 15 minutes, and 85% (n= 52) were positive within the first hour. It was concluded that, Carba NP test showed high sensitivity and specificity than the MHT and the results can be obtained more rapidly for the presence of carbapenemases in Enterobacteriaceae. The use of MHT alone is not recommended to confirm the presence of carbapenemases produced by Enterobacteriaceae. On the other hand Carba NP test can be used for this purpose, however molecular analysis should be considered for suspicious negative results.


Assuntos
Proteínas de Bactérias/análise , Enterobacteriaceae/enzimologia , Ensaios Enzimáticos/métodos , beta-Lactamases/análise , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Carbapenêmicos/farmacologia , Cilastatina/farmacologia , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/isolamento & purificação , Ensaios Enzimáticos/normas , Humanos , Imipenem/farmacologia , Testes de Sensibilidade Microbiana , Fenótipo , Sensibilidade e Especificidade , beta-Lactamases/genética
10.
Mikrobiyol Bul ; 50(1): 21-33, 2016 Jan.
Artigo em Turco | MEDLINE | ID: mdl-27058326

RESUMO

Carbapenems are the choice of treatment in infections caused by multidrug resistant Enterobacteriaceae. In recent years carbapenem-resistant Enterobacteriaceae isolates due to carbapenemases have been increasingly reported worldwide. Multicenter studies on carbapenemases are scarce in Turkey. The aim of this study was to determine the distribution of carbapenemases from different parts of Turkey as a part of the European Survey of Carbapenemase Producing Enterobacteriaceae (EuSCAPE) project. Beginning in November 2013, carbapenem-resistant isolates resistant to at least one of the agents, namely imipenem, meropenem, and ertapenem were sent to the coordinating center. Minimum inhibitory concentrations for these carbapenems were determined by microdilution tests following EUCAST guidelines. Production of carbapenemase was confirmed by combination disk synergy tests. Types of carbapenemases were investigated using specific primers for VIM, IMP; NDM, KPC and OXA-48 genes by multiplex polymerase chain reaction. In a six month period, 155 suspected carbapenemase-positive isolates were sent to the coordinating center of which 21 (13.5%) were E.coli and 134 (86.5%) were K.pneumoniae. Nineteen (90.5%) strains among E.coli and 124 (92.5%) strains among K.pneumoniae were shown to harbour at least one carbapenemase gene by molecular tests, with a total of 92.3% (143/155). Carbapenemases were determined as a single enzyme in 136 strains (OXA-48: 84.6%; NDM: 6.3%; VIM: 2.8%; IMP: 1.4%) and as a combination in seven isolates (OXA-48 + NDM: 2.1%; OXA-48 + VIM: 2.1%; VIM + NDM: 0.7%). KPC was not detected in any of the isolates. According to the microdilution test results, resistance to imipenem, meropenem and ertapenem in OXA-48 isolates were 59.5%, 52.9% and 100%, respectively. The combination disk synergy test was 100% compatible with the molecular test results. As most of the OXA-48 producing isolates were susceptible to meropenem but all were resistant to ertapenem, ertapenem seems to be the most sensitive agent in screening carbapenemases in areas where OXA-48 is prevalent and phenotypic combination tests can be useful in centers where molecular tests are not available.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Carbapenêmicos/farmacologia , Escherichia coli/enzimologia , Klebsiella pneumoniae/enzimologia , beta-Lactamases/metabolismo , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana Múltipla/genética , Ertapenem , Escherichia coli/efeitos dos fármacos , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Humanos , Imipenem/farmacologia , Klebsiella pneumoniae/efeitos dos fármacos , Meropeném , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase Multiplex , Fenótipo , Tienamicinas/farmacologia , Turquia , beta-Lactamases/genética , beta-Lactamas/farmacologia
12.
Hum Vaccin Immunother ; 12(2): 308-13, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26325175

RESUMO

Successful vaccination policies for protection from invasive pneumococcal diseases (IPD) dependent on determination of the exact serotype distribution in each country. We aimed to identify serotypes of pneumococcal strains causing IPD in children in Turkey and emphasize the change in the serotypes before and after vaccination with 7-valent pneumococcal conjugate vaccine (PCV-7) was included and PCV-13 was newly changed in Turkish National Immunization Program. Streptococcus pneumoniae strains were isolated at 22 different hospitals of Turkey, which provide healthcare services to approximately 65% of the Turkish population. Of the 335 diagnosed cases with S. pneumoniae over the whole period of 2008-2014, the most common vaccine serotypes were 19F (15.8%), 6B (5.9%), 14 (5.9%), and 3 (5.9%). During the first 5 y of age, which is the target population for vaccination, the potential serotype coverage ranged from 57.5 % to 36.8%, from 65.0% to 44.7%, and from 77.4% to 60.5% for PCV-7, PCV-10, and PCV-13 in 2008-2014, respectively. The ratio of non-vaccine serotypes was 27.2% in 2008-2010 whereas was 37.6% in 2011-2014 (p=0.045). S. penumoniae serotypes was less non-susceptible to penicillin as compared to our previous results (33.7 vs 16.5 %, p=0.001). The reduction of those serotype coverage in years may be attributed to increasing vaccinated children in Turkey and the increasing non-vaccine serotype may be explained by serotype replacement. Our ongoing IPD surveillance is a significant source of information for the decision-making processes on pneumococcal vaccination.


Assuntos
Vacina Pneumocócica Conjugada Heptavalente/imunologia , Infecções Pneumocócicas/epidemiologia , Vacinas Pneumocócicas/imunologia , Streptococcus pneumoniae/classificação , Vacinas Conjugadas/imunologia , Antibacterianos/farmacologia , Pré-Escolar , Feminino , Hospitais , Humanos , Programas de Imunização , Masculino , Testes de Sensibilidade Microbiana , Infecções Pneumocócicas/microbiologia , Infecções Pneumocócicas/prevenção & controle , Estudos Prospectivos , Sorogrupo , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pneumoniae/isolamento & purificação , Turquia/epidemiologia , Vacinação
13.
Mikrobiyol Bul ; 49(3): 467-72, 2015 Jul.
Artigo em Turco | MEDLINE | ID: mdl-26313289

RESUMO

Meningococcal conjunctivitis is a rare but important infection since it can lead to severe complications and can threaten public health. It may emerge in two forms, either primary or secondary type which is developed after a systemic infection. Accurate diagnosis of primary meningococcal conjunctivitis is very important in addition to ocular complications which can result in loss of vision, the condition can also lead to severe complications like systemic meningococcal disease. However, the lack of specific symptoms which can distinguish meningococcal conjunctivitis from other forms of bacterial conjunctivitis, initiation of empiric antibiotic therapy without performing culture and nonaccurate differentiation of Neisseria gonorrhoeae and Neisseria meningitidis with commercial kits/systems used in laboratories cause problematic situations. This report describes a case of primary unilateral conjunctivitis in a 14-month-old girl caused by non-groupable N.meningitidis that was resolved without sequelae following treatment. A pre-healthy 14-month-old girl was brought to the pediatric emergency department with redness, crusts and discharge in the left eye that had begun two days earlier. Ocular examination revealed hyperemia and purulent discharge in the left conjunctiva. Purulent conjunctivitis was diagnosed. A conjunctival swab specimen was taken for culture, and the patient was started on topical netilmicin (4x1), topical fusidic acid (2x1) and artificial tears. Microscopic examination of the conjunctival swab revealed polymorphonuclear leukocytes and no visible bacteria. Catalase and oxidase positive, gram-negative diplococci grew purely in culture. The first Gram stain preparation was evaluated again after the growth and small numbers of gram-negative diplococci were observed. The cultivated bacteria were identified as N.meningitidis using MALDI-TOF MS (Bruker Daltonics, Germany), but as N.gonorrhoeae with BBL Crystal N/H (Neisseria/Haemophilus) (BD Diagnostic Systems, MD) identification system. The isolate was identified as N.meningitidis by polymerase chain reaction method. The isolate was sent to the Public Health Institution of Turkey for confirmation and serotyping. It was confirmed as non-groupable N.meningitidis. This is the first report of conjunctivitis caused by non-groupable N.meningitidis from Turkey. We wish to emphasize the importance of Gram staining and differentiation of the species by automatized systems in diagnosis, netilmicin may be one of the options for empiric treatment and in terms of public health the most appropriate approach may be evaluation of the severity of conjunctivitis and causative serogroup which depends on case-based approach.

16.
Ann Clin Microbiol Antimicrob ; 13: 44, 2014 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-25223381

RESUMO

INTRODUCTION: Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most important nosocomial pathogens and is also emerging in Turkish hospitals. The aim of this study was to determine the antimicrobial susceptibility profiles of MRSA isolated from Turkish hospitals. MATERIALS AND METHODS: A total of 397 MRSA strains isolated from 12 hospitals in Turkey were included to present study. Antimicrobial susceptibilities were tested using agar dilution method. Presence of ermA, ermB, ermC, msrA, tetM, tetK, linA and aac-aph genes were studied by PCR. RESULTS: All strains were susceptible to vancomycin and linezolid. The susceptibility rates for fusidic acid, lincomycin, erythromycin, tetracyclin, gentamycin, kanamycin, and, ciprofloxacin were 91.9%, 41.1%, 27.2%, 11.8%, 8.5%, 8.3% and 6.8%, respectively. Lincomycin inactivation was positive for 3 isolates. Of 225 erythromycin resistant isolates 48 had ermA, 20 had ermC, and 128 had ermA-C. PCR was negative for 15 strains. Of 3 isolates with lincomycin inactivation one had linA and msrA. Of 358 gentamycin resistant isolates 334 had aac-aph and 24 were negatives. Among 350 tetracyclin resistant isolates 314 had tetM. Of 36 tetM negative isolates 10 had tetK. CONCLUSION: MRSA isolates from Turkish hospitals were multiresistant to antimicrobials. Quinolone and gentamycin resistance levels were high and macrolide and lincosamide resistance were relatively low. Susceptibility rates for fusidic asid were high. Linezolide and vancomycin resistance are not emerged. The most common resistance genes were ermA, tetM and aac-aph. Evolution of antimicrobial susceptibilities and resistance genes profiles of MRSA isolates should be surveyed at regional and national level for accurate treatment of patients and to control dissemination of resistance genes.


Assuntos
Antibacterianos/farmacologia , Infecção Hospitalar/microbiologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Infecções Estafilocócicas/microbiologia , Farmacorresistência Bacteriana Múltipla , Genes Bacterianos , Hospitais , Humanos , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Turquia
17.
Mikrobiyol Bul ; 48(2): 191-200, 2014 Apr.
Artigo em Turco | MEDLINE | ID: mdl-24819257

RESUMO

Although Salmonella enterica serotype Paratyphi B is the less frequently isolated serotype worldwide and in Turkey, it is the most common serotype in our hospital, with a marked increase in 2007. The purpose of this study was to investigate the antibiotic susceptibility and the extended spectrum beta-lactamase (ESBL) profile, and molecular epidemiology of S. Paratyphi B isolates detected in our hospital microbiology laboratory. Seventy isolates identified as S. Paratyphi B from 109 Salmonella isolates obtained from clinical specimens from different patients between October 2005 and December 2012, were included in the study. In addition to conventional methods, isolates were identified using the Phoenix automated microbiology system (Becton Dickinson, USA). Serotyping of the isolates was performed on the basis of slide agglutination and the Kauffmann-White scheme. The antibiotic susceptibility of the isolates was determined using the BD Phoenix' automated system and disk diffusion test. ESBL enzymes were investigated using the combined disk test, isoelectric focusing, polymerase chain reaction (PCR) and sequence analysis. The molecular epidemiology of the 51 isolates obtained between October 2005 and August 2008 was examined with pulsed-field gel electrophoresis (PFGE) using the XbaI enzyme. S. Paratyphi B isolates were obtained from 70 specimens (46 blood, 16 fecal, 4 bone marrow, 2 urine and 2 wound) each from different patients. Resistance to nalidixic acid was determined in 18.6%, resistance to ampicillin, cefotaxime and cefepime in 2.9% and to ceftazidime and co-trimoxazole in 1.4% of the isolates. ESBL production was detected only in two isolates; in one TEM-1 was accompanied by CTX-M-15 and in the other isolate CTX-M-3 was found. Forty-six of the 51 isolates (90%) were found to be genetically related by PFGE and were placed in cluster A. The distribution of the isolates in cluster A revealed six subtypes as A1 (n= 7), A2 (n= 11), A3 (n= 7), A4 (n= 18), A5 (n= 2) and A6 (n= 1). Three different patterns not related to the cluster A were determined in the remaining five isolates (two were B, one of each was C, D and E). In conclusion, although the rate of antibiotic resistance was low in the S. Paratyphi B isolates in our hospital, rare types of ESBLs such as CTX-M-3 and CTX-M-15 were detected in Salmonellae. As far as the current literature is considered, this is the first report in Turkey of blaCTX-M-15 in Salmonella spp. and blaCTX-M-3 genes in S. Paratyphi B. The results may indicate a possible future threat to the treatment of Salmonella infections. Since most of the isolates were genetically related, this might suggest an epidemic in our region.


Assuntos
Febre Paratifoide/microbiologia , Salmonella paratyphi B/isolamento & purificação , beta-Lactamases/metabolismo , Testes de Aglutinação , Análise por Conglomerados , Desoxirribonucleases de Sítio Específico do Tipo II , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Farmacorresistência Bacteriana , Eletroforese em Gel de Campo Pulsado , Humanos , Focalização Isoelétrica , Testes de Sensibilidade Microbiana/métodos , Febre Paratifoide/epidemiologia , Reação em Cadeia da Polimerase , Salmonella paratyphi B/classificação , Salmonella paratyphi B/efeitos dos fármacos , Salmonella paratyphi B/enzimologia , Análise de Sequência , Sorotipagem , Turquia/epidemiologia , beta-Lactamases/genética
18.
Mikrobiyol Bul ; 48(2): 201-12, 2014 Apr.
Artigo em Turco | MEDLINE | ID: mdl-24819258

RESUMO

Stenotrophomonas maltophilia, which is a non-fermentative gram-negative bacillus, has an increasing importance in nosocomial and opportunistic infections. Since it exhibits resistance to numerous broad-spectrum antibiotics such as aminoglycosides, beta-lactams and tetracyclines, it may considerably limit empirical treatment options. Trimethoprim-sulfamethoxazole (SXT) is recommended as the first-line therapy in the treatment of S.maltophilia infections thanks to its high potency and usefulness in a range of patients. In recent years, however, studies in different geographical regions have started to report resistance to SXT. In this study, we aimed to investigate the genes sul1, sul2, dfrA9, dfrA10, dfrA20 and class I, class II integron gene cassettes which are known to play role in SXT resistance among SXT-resistant S.maltophilia strains. A total of 618 S.maltophilia strains isolated from various clinical samples of 339 patients between January 2006 and October 2011 at the laboratory of Medical Microbiology Department, Faculty of Medicine, Karadeniz Technical University, Trabzon, Turkey, were included in the study. The isolates were identified by both conventional methods and the Phoenix automated identification system (Becton Dickinson, USA). SXT resistance was determined in the isolates of 32 patients (32/339, 9.4%) by both the automated system and agar dilution method of them 29 (90.6%) were hospital-acquired, and 3 (9.4%) were community-acquired. The genes which are known as SXT resistance determining genes including sul1, sul2, dfr genes, and class I and class II integron gene cassettes were analyzed by using specific primers with polymerase chain reaction in the 32 SXT-resistant isolates. Subsequently, nucleotide sequence analysis of the amplified materials was performed. As a result of this assay, the presence of class I integron gene cassette and sul1 gene were detected in one isolate. Nucleotide sequence analysis of the gene cassette revealed oxacilinase (oxa2) type of beta-lactamase, an aminoglycoside 6'-N-acetyltransferase [aac(6')-IIc], leading to resistance of aminoglycosides, and a quaternary ammonium compounds resistance gene (qacF), respectively. In conclusion, to best of our knowledge the sequences of class I integron gene cassette including oxa2, aac(6')-IIc, qacF genes were identified in S.maltophilia for the first time. It should be kept in mind that the co-presence of a class I integron gene cassette and the sul1 gene in S.maltophilia may lead to the development of multi-drug resistance and may act as a potential source for the dissemination of resistance.


Assuntos
Anti-Infecciosos/farmacologia , Proteínas de Bactérias/genética , Infecções por Bactérias Gram-Negativas/microbiologia , Integrons/genética , Stenotrophomonas maltophilia/genética , Combinação Trimetoprima e Sulfametoxazol/farmacologia , Anti-Infecciosos/uso terapêutico , Infecções Comunitárias Adquiridas/tratamento farmacológico , Infecções Comunitárias Adquiridas/microbiologia , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana/genética , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Humanos , Stenotrophomonas maltophilia/efeitos dos fármacos , Stenotrophomonas maltophilia/isolamento & purificação , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico
19.
Mikrobiyol Bul ; 47(4): 571-81, 2013 Oct.
Artigo em Turco | MEDLINE | ID: mdl-24237426

RESUMO

Staphylococcus aureus is one of the most frequent agents causing hospital infections. S.aureus has a great ability to adapt itself to variety of conditions and successful clones can be epidemic and even pandemic by its ability spread from one continent to another. The aims of this study were to detect spa types of 397 methicillin-resistant S.aureus (MRSA) strains isolated from 12 centers in different geographical regions of Turkey from 2006 to 2008, and to investigate their clonality by PFGE and MLST typing. Additionally, 91 MRSA from four of those 12 centers isolated during 2011 were also studied for their spa types. PFGE profiles indicated the presence of a major pulsotype, namely pulsotype A with a rate of 91.4% (363/397), followed by pulsotype B (n= 18, 4.5%) and pulsotype C (n= 11, 2.8%). Among isolates tested 363 (91.4%) were SCCmec type III, 30 (7.6%) were SCCmec type IV. Sequence analysis of representative isolates revealed that ST239 (85.1%) was the most common MLST type followed by two MLST types ST737 (4%), and ST97 (2.8%), both SCCmec type IV. Two isolates were ST80 with SCCmec type IV. Of 397 isolates, 338 (85.1%) were t030, followed by t005 (2.5%) and t632 (2%). Among MRSA isolated during 2011, 64 (70.3%) of 91 were t030, 4 (4.4%) were t005, 2 (2.2%) were t015, and 2 (2.2%) were t1094. Among centers the t030 prevalence of 2006-2008 isolates ranged from 59-100%. The highest t030 prevalence was found in Ankara (100%) and lowest in Trabzon (59%) provinces which are located at central and northestern Anatolia, respectively. In Istanbul province, the prevalence of t030 was 94.5% among 2006-2008 isolates which decreased to 55.5% among 2011 isolates. Also a decrease in t030 rates was observed among samples from Konya and Trabzon but not from Aydin. Our results showed that the most common MRSA clone in Turkey is ST 239-SCCmec type III, t030 which persisted during the six years of the study period. Presence of PVL toxin gene was tested by PCR and 5 (3%) isolates found to be positive, of them two were SCCmec Type IV-ST80 and three were SCCmec Type III-ST239. This study is the largest epidemiological survey ever done in Turkey which showed presence of a hospital Turkish clone TR09 (ST239-SCCmecIII-t030) and a community clone TR10 (ST737-SCCmecIV-t005) largely disseminated in Turkey.


Assuntos
Infecção Hospitalar/microbiologia , Staphylococcus aureus Resistente à Meticilina/classificação , Infecções Estafilocócicas/microbiologia , Toxinas Bacterianas/análise , Infecção Hospitalar/epidemiologia , DNA Bacteriano/isolamento & purificação , Eletroforese em Gel de Campo Pulsado , Exotoxinas/análise , Humanos , Leucocidinas/análise , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Tipagem de Sequências Multilocus , Reação em Cadeia da Polimerase , Prevalência , Infecções Estafilocócicas/epidemiologia , Turquia/epidemiologia
20.
Mikrobiyol Bul ; 47(4): 650-7, 2013 Oct.
Artigo em Turco | MEDLINE | ID: mdl-24237433

RESUMO

Hepatitis C virus (HCV), the major cause of transfusion-associated hepatitis, is an important public health problem in the world as well as in Turkey. HCV is grouped as six distinct genotypes and a large number of closely-related subtypes. Genotyping of HCV is an important tool for providing epidemiological data, prediction of prognosis, and optimization of antiviral therapy. This study was carried out to determine the distribution of HCV genotypes in hepatitis C patients residing in different provinces of the Eastern Black Sea Region, Turkey. A total of 304 HCV-RNA positive cases (151 male, 153 female; age range: 11-93 years, mean age: 55.2 ± 13.3 years) who were admitted to the Molecular Microbiology Unit of Department of Medical Microbiology, Karadeniz Technical University Faculty of Medicine, between January 2009 to December 2012, were included in the study. HCV genotypes were detected in plasma samples of the patients by using commercial assays [INNO-LiPA HCV II (Innogenetics, Belgium) or Abbott RealTime HCV Genotype II (Abbott Molecular Inc, USA)]. Due to the ambiguous genotyping results in some samples with these methods, an in-house multiplex polymerase chain reaction (PCR) assay with genotype-specific primers was also used in the study. Similar to the previous reports from Turkey, our results showed that four HCV genotypes (1, 2, 3, and 4) prevailed in the Eastern Black Sea Region and the predominant genotype and subtype were genotype 1 (92.8%) and 1b (87.5%), respectively. Distribution of genotypes were observed to vary according to the province. Prevalences of subtype 1a, genotype 2, 3, and 4 were noted as 5.3%, 1.6%, 4.9%, and 0.7%, respectively. Furthermore, the samples from Giresun, Gumushane and Bayburt provinces, which are relatively less immigrated, had higher genotype 1, and the prevalence rates in the region was affected by the presence of non-citizen residents. This study is the first report on distribution of HCV genotypes in chronic hepatitis C patients living in the provinces of Eastern Black Sea Region. Moreover, genotype-specific multiplex PCR assay could be useful in resolving certain methodological problems such as "ghost bands" encountered in line probe assay (LiPA) and multiple genotypes (including genotype 4) observed in real-time PCR during the characterization of HCV genotypes seen in Turkey.


Assuntos
Hepacivirus/genética , Hepatite C/virologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Genótipo , Hepacivirus/classificação , Humanos , Masculino , Pessoa de Meia-Idade , Turquia , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...