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1.
Article in English | WPRIM | ID: wpr-887737

ABSTRACT

Objective@#To evaluate multidrug resistant loop-mediated isothermal amplification (MDR-LAMP) assay for the early diagnosis of multidrug-resistant tuberculosis and to compare the mutation patterns associated with the @*Methods@#MDR-LAMP assay was evaluated using 100 @*Results@#The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of MDR-LAMP were 85.5%, 93.6%, 96.7%, and 74.4% for the detection of resistance to isoniazid and rifampicin, respectively, and 80.5%, 92.3%, 98.6%, and 41.4% for the detection of @*Conclusion@#MDR-LAMP is a rapid and accessible assay for the laboratory identification of rifampicin and isoniazid resistance of


Subject(s)
Antitubercular Agents , Bacterial Proteins/genetics , Catalase/genetics , DNA, Bacterial/analysis , DNA-Directed RNA Polymerases/genetics , Drug Resistance, Multiple, Bacterial/genetics , Isoniazid , Molecular Diagnostic Techniques/methods , Mutation , Mycobacterium tuberculosis/isolation & purification , Nucleic Acid Amplification Techniques/methods , Oxidoreductases/genetics , Phenotype , Rifampin , Whole Genome Sequencing
2.
Rev. Soc. Bras. Med. Trop ; 54: e02622020, 2021.
Article in English | ColecionaSUS, LILACS, ColecionaSUS, SES-SP | ID: biblio-1143877

ABSTRACT

Abstract INTRODUCTION: Carbapenemase-resistant enterobacteria that produce the bla NDM gene are found worldwide. However, this is the first report of blaNDM in Klebsiella aerogenes in Brazil. METHODS: The identification of bacterial species was performed using anautomated system and confirmed by biochemical tests, 16S rRNA gene sequencing, and detection of resistance genes. RESULTS: The clinical isolate showed minimum inhibitory concentration resistance to meropenem and polymyxin B at 8mg/L and 4mg/L, respectively. Only the blaNDM gene was detected. CONCLUSIONS: The current report of the blaNDM gene in isolated MDR enterobacteria indicates that this gene can spread silently in a hospital setting.


Subject(s)
Enterobacter aerogenes/genetics , Bacterial Proteins , beta-Lactamases/genetics , Brazil , RNA, Ribosomal, 16S , Microbial Sensitivity Tests , Drug Resistance, Multiple, Bacterial/genetics , Enterobacteriaceae , Klebsiella pneumoniae/genetics , Anti-Bacterial Agents/pharmacology
3.
Mem. Inst. Oswaldo Cruz ; 115: e200520, 2020. tab, graf
Article in English | LILACS | ID: biblio-1154871

ABSTRACT

BACKGROUND The evaluation of procedures for drug susceptibility prediction of Mycobacterium tuberculosis based on genomic data against the conventional reference method test based on culture is realistic considering the scenario of growing number of tools proposals based on whole-genome sequences (WGS). OBJECTIVES This study aimed to evaluate drug susceptibility testing (DST) outcome based on WGS tools and the phenotypic methods performed on isolates of M. tuberculosis Lineage 1 from the state of Pará, Brazil, generally associated with low levels of drug resistance. METHODOLOGY Culture based DST was performed using the Proportion Method in Löwenstein-Jensen medium on 71 isolates that had been submitted to WGS. We analysed the seven main genome sequence-based tools for resistance and lineage prediction applied to M. tuberculosis and for comparison evaluation we have used the Kappa concordance test. FINDINGS When comparing the WGS-based tools against the DST, we observed the highest level of agreement using TB-profiler. Among the tools, TB-profiler, KvarQ and Mykrobe were those which identified the largest number of TB-MDR cases. Comparing the four most sensitive tools regarding resistance prediction, agreement was observed for 43 genomes. MAIN CONCLUSIONS Drug resistance profiling using next-generation sequencing offers rapid assessment of resistance-associated mutations, therefore facilitating rapid access to effective treatment.


Subject(s)
Humans , Tuberculosis, Multidrug-Resistant/genetics , Drug Resistance, Multiple, Bacterial/genetics , Mycobacterium tuberculosis/drug effects , Mycobacterium tuberculosis/genetics , Antitubercular Agents/pharmacology , Brazil , Pharmaceutical Preparations , Microbial Sensitivity Tests , Tuberculosis, Multidrug-Resistant/drug therapy , Drug Resistance, Multiple, Bacterial/drug effects , Whole Genome Sequencing , Mycobacterium tuberculosis/isolation & purification , Antitubercular Agents/therapeutic use
4.
Rev. Soc. Bras. Med. Trop ; 53: e20200064, 2020. tab, graf
Article in English | ColecionaSUS, LILACS, ColecionaSUS, SES-SP | ID: biblio-1136871

ABSTRACT

Abstract INTRODUCTION: Carbapenem-resistant Klebsiella pneumoniae infection lacks treatment options and is associated with prolonged hospital stays and high mortality rates. The production of carbapenemases is one of the most important factors responsible for this multi-resistance phenomenon. METHODS: In the present study, we analyzed the presence of genes encoding carbapenemases in K. pneumoniae isolates circulating in one of the public hospitals in the city of Aracaju, Sergipe, Brazil. We also determined the best combination of drugs that display in vitro antimicrobial synergy. First, 147 carbapenem-resistant K. pneumoniae isolates were validated for the presence of blaKPC, bla GES, bla NDM, bla SPM, bla IMP, bla VIM, and bla OXA-48 genes using multiplex polymerase chain reaction. Thereafter, using two isolates (97 and 102), the role of double and triple combinational drug therapy as a treatment option was analyzed. RESULTS: Seventy-four (50.3%) isolates were positive for bla NDM, eight (5.4%) for bla KPC, and one (1.2%) for both bla NDM and bla KPC. In the synergy tests, double combinations were better than triple combinations. Polymyxin B and amikacin for isolate 97 and polymyxin B coupled with meropenem for isolate 102 showed the best response. CONCLUSIONS: Clinicians in normal practice use multiple drugs to treat infections caused by multi-resistant microorganism; however, in most cases, the benefit of the combinations is unknown. In vitro synergistic tests, such as those described herein, are important as they might help select an appropriate multi-drug antibiotic therapy and a correct dosage, ultimately reducing toxicities and the development of antibiotic resistance.


Subject(s)
Humans , Bacterial Proteins/genetics , beta-Lactamases/genetics , Klebsiella Infections/microbiology , Klebsiella pneumoniae/drug effects , Anti-Bacterial Agents/pharmacology , Brazil , DNA, Bacterial , Microbial Sensitivity Tests , Polymerase Chain Reaction , Prevalence , Drug Resistance, Multiple, Bacterial/genetics , Klebsiella pneumoniae/isolation & purification , Klebsiella pneumoniae/genetics
5.
Mem. Inst. Oswaldo Cruz ; 115: e200055, 2020. tab, graf
Article in English | SES-SP, LILACS, SES-SP | ID: biblio-1135234

ABSTRACT

BACKGROUND Tuberculosis (TB) is an infectious disease caused by the bacterium Mycobacterium tuberculosis, and the number of new cases of multidrug resistant TB (MDR-TB), pre extensively drug-resistant TB (pre-XDR-TB) and extensively drug-resistant TB (XDR-TB) has increased considerably worldwide. OBJECTIVES Herein, using 156 M. tuberculosis isolates from 106 patients previously classified as MDR or pre-XDR or XDR isolates, we investigated the genetic mutation profiles associated with phenotypic resistances in patients with MDR-TB, pre-XDR-TB and XDR-TB, treatment outcomes and resistance evolution. METHODS Molecular analyses were performed by partial sequencing of the rpoB, katG, gyrA, gyrB, rrs genes and analysis of the fabG-inhA promoter region. Clinical, epidemiologic and demographic data were obtained from the TB Notification database system of São Paulo (TB-WEB) and the Information System for Special Tuberculosis Treatments (SITE-TB). FINDINGS Drug resistance was attributed to previously known mutations and a novel Asp449Val mutation in gyrB was observed in four isolates from the same patient. Ten patients had more than one isolate evaluated and eight of these patients displayed resistance progression. MAIN CONCLUSIONS The present study is the first to report the frequency of mutations related to second-line drug resistance in MDR-TB, pre-XDR-TB and XDR-TB isolates. The results could lead to the improvement of available technologies for the rapid detection of drug resistant TB.


Subject(s)
Humans , Male , Female , Adolescent , Adult , Young Adult , Tuberculosis, Multidrug-Resistant/microbiology , Drug Resistance, Multiple, Bacterial/genetics , Mutation/genetics , Mycobacterium tuberculosis/drug effects , Mycobacterium tuberculosis/genetics , Antitubercular Agents/pharmacology , Socioeconomic Factors , Brazil , Microbial Sensitivity Tests , Extensively Drug-Resistant Tuberculosis/microbiology , Middle Aged , Mycobacterium tuberculosis/isolation & purification
6.
Braz. j. infect. dis ; 23(6): 371-380, Nov.-Dec. 2019. tab, graf
Article in English | LILACS | ID: biblio-1089307

ABSTRACT

ABSTRACT Introduction: The presence of Acinetobacter baumannii outside hospitals remains unclear. This study aimed to determine the prevalence of multidrug-resistance (MDR) A. baumannii in the extra-hospital environment in Mthatha, South Africa and to investigate the frequency of carbapenemase-encoding genes. Material and Methods: From August 2016 to July 2017 a total of 598 abattoir samples and 689 aquatic samples were collected and analyzed presumptively by cultural methods for the presence of A. baumannii using CHROMagar™ Acinetobacter medium. Species identification was performed by autoSCAN-4 (Dade Behring Inc., IL) and confirmed by the detection of their intrinsic blaOXA-51 gene. Confirmed MDR A. baumannii isolates were screened for the presence of carbapenemase-encoding genes, ISAba1 insertion sequence and integrase intI1. Results: In total, 248 (19.3%) Acinetobacter species were isolated. Acinetobacter. baumannii was detected in 183 (73.8%) of which 85 (46.4%) and 98 (53.6%) were recovered from abattoir and aquatic respectively. MDR A. baumannii was detected in 56.5% (48/85) abattoir isolates and 53.1% (52/98) aquatic isolates. Isolates showed high resistance to antimicrobials most frequently used to treat Acinetobacter infections such as piperacillin/tazobactam; abattoir (98% of isolates resistant), aquatic (94% of isolates resistant), ceftazidime (84%, 83%), ciprofloxacin (71%, 70%), amikacin (41%, 42%), imipenem (75%, 73%), and meropenem (74%, 71%). All the isolates were susceptible to tigecycline and colistin. All the isolates carried blaOXA-51-like. The blaOXA-23 was detected in 32 (66.7%) abattoir isolates and 11 (21.2%) aquatic isolates. The blaOXA-58-like was positive in 7 (14.6%) and 4 (7.7%) abattoir and aquatic isolates, respectively. Both groups of isolates lacked blaOXA-24-like, blaIMP-type, blaVIM-type, blaNDM-1, blaSIM, blaAmpC, ISAba1 and inI1. Isolates showed high level of Multiple Antibiotic Resistance Index (MARI) ranging from 0.20-0.52. Conclusion: Extra-hospital sources such as abattoir and aquatic environments may be a vehicle of spread of MDR A. baumannii strains in the community and hospital settings.


Subject(s)
Humans , Acinetobacter Infections/microbiology , Acinetobacter Infections/drug therapy , Drug Resistance, Multiple, Bacterial/genetics , Acinetobacter baumannii/isolation & purification , Anti-Bacterial Agents/therapeutic use , South Africa/epidemiology , Acinetobacter Infections/transmission , Acinetobacter Infections/epidemiology , Microbial Sensitivity Tests , Polymerase Chain Reaction , Prevalence , Cross-Sectional Studies , Prospective Studies , Acinetobacter baumannii/genetics
7.
Mem. Inst. Oswaldo Cruz ; 114: e190079, 2019. graf
Article in English | LILACS | ID: biblio-1040613

ABSTRACT

A total of 124 Neisseria gonorrhoeae isolates recovered during a 12-year period (2003-2015) from outpatients assisted at Centro de Referência e Treinamento DST/AIDS-CRT of São Paulo city, Brazil, were analysed. The following resistance rates were observed: penicillin-59.6%, ciprofloxacin-15.3%, and azithromycin-6.7%. Although reduced susceptibility to these drugs was observed since 2003, no ceftriaxone-resistant isolates were detected. Ciprofloxacin- and azithromycin non-susceptible isolates were grouped in 11 clusters. Mutations were detected in GyrA and ParC of isolates 124 and 260, and a C2611T substitution on 23S rRNA alleles was also observed in isolate 260. Both isolates belonged to ST1901/ST6210 (MSLT/NG-MAST schemes).


Subject(s)
Humans , Drug Resistance, Multiple, Bacterial/genetics , Anti-Bacterial Agents/pharmacology , Neisseria gonorrhoeae/drug effects , Neisseria gonorrhoeae/genetics , Time Factors , Urban Population , Microbial Sensitivity Tests , Drug Resistance, Multiple, Bacterial/drug effects , Mutation
8.
Rev. Soc. Bras. Med. Trop ; 52: e20180352, 2019. tab
Article in English | LILACS | ID: biblio-1041560

ABSTRACT

Abstract INTRODUCTION: The emergence of New Delhi metallo-β-lactamase (NDM) is concernig because it reduces the antibiotic therapy options for bacterial infections. METHODS: Resistant and virulent genes from an isolate of Klebsiella pneumoniae derived from a patient with sepsis in a hospital in Recife-PE, Brazil, were investigated using PCR and DNA sequencing. RESULTS: bla NDM-1, aac(6')-Ib-cr and acrB resistance genes, and cps and mrkD virulence genes were detected. CONCLUSIONS To our knowledge, this is the first report on bla NDM-1 in Recife-PE. This detection alerts researchers to the need to control the spread of bla NDM-1 resistance gene by this bacterium in Brazil.


Subject(s)
Humans , Female , Bacterial Proteins/genetics , Virulence/genetics , beta-Lactamases/genetics , Drug Resistance, Multiple, Bacterial/genetics , Klebsiella pneumoniae/genetics , Anti-Bacterial Agents/pharmacology , Microbial Sensitivity Tests , Polymerase Chain Reaction , Sequence Analysis, DNA , Sepsis/microbiology , Klebsiella pneumoniae/drug effects , Klebsiella pneumoniae/enzymology
9.
Braz. j. infect. dis ; 22(5): 438-441, Sept.-Oct. 2018. tab, graf
Article in English | LILACS | ID: biblio-1039218

ABSTRACT

ABSTRACT Acinetobacter baumannii is one of the most frequent Gram-negative opportunistic pathogens associated with hospital-acquired infection worldwide. We briefly describe A. baumannii isolates that were recovered from surrounding ICU bed surfaces, exhibiting multidrug resistance phenotype and belonging to some widely spread clonal complexes of clinical A. baumannii isolates.


Subject(s)
Beds/microbiology , Drug Resistance, Multiple, Bacterial/genetics , Acinetobacter baumannii/isolation & purification , Intensive Care Units , Bacteria/isolation & purification , Bacteria/drug effects , Brazil , Microbial Sensitivity Tests , Cross Infection/microbiology , Acinetobacter baumannii/drug effects , Acinetobacter baumannii/genetics , Tertiary Care Centers , Genes, Bacterial
10.
Braz. j. med. biol. res ; 51(8): e7044, 2018. graf
Article in English | LILACS | ID: biblio-951748

ABSTRACT

In this study, we screened differentially expressed genes in a multidrug-resistant isolate strain of Clostridium perfringens by RNA sequencing. We also separated and identified differentially expressed proteins (DEPs) in the isolate strain by two-dimensional electrophoresis (2-DE) and mass spectrometry (MS). The RNA sequencing results showed that, compared with the control strain, 1128 genes were differentially expressed in the isolate strain, and these included 227 up-regulated genes and 901 down-regulated genes. Bioinformatics analysis identified the following genes and gene categories that are potentially involved in multidrug resistance (MDR) in the isolate strain: drug transport, drug response, hydrolase activity, transmembrane transporter, transferase activity, amidase transmembrane transporter, efflux transmembrane transporter, bacterial chemotaxis, ABC transporter, and others. The results of the 2-DE showed that 70 proteins were differentially expressed in the isolate strain, 45 of which were up-regulated and 25 down-regulated. Twenty-seven DEPs were identified by MS and these included the following protein categories: ribosome, antimicrobial peptide resistance, and ABC transporter, all of which may be involved in MDR in the isolate strain of C. perfringens. The results provide reference data for further investigations on the drug resistant molecular mechanisms of C. perfringens.


Subject(s)
Animals , Bacterial Proteins/genetics , Clostridium perfringens/genetics , Sequence Analysis, RNA/methods , Genes, MDR , Drug Resistance, Multiple, Bacterial/genetics , Mass Spectrometry/methods , Bacterial Proteins/metabolism , Electrophoresis, Gel, Two-Dimensional/methods , Gene Expression Regulation, Bacterial/genetics , Genome, Bacterial/genetics , Clostridium perfringens/classification , Clostridium perfringens/drug effects , Clostridium perfringens/metabolism , DNA, Complementary , Proteome/genetics , Transcriptome/genetics , Gene Ontology
11.
Rev. Soc. Bras. Med. Trop ; 50(6): 764-768, Nov.-Dec. 2017. tab, graf
Article in English | LILACS | ID: biblio-897038

ABSTRACT

Abstract INTRODUCTION: Pseudomonas aeruginosa, an important pathogen globally, presents several resistance mechanisms. This study aimed to investigate the presence of bla GES in clinical isolates of Pseudomonas aeruginosa obtained from various clinical specimens from patients admitted to three different hospitals in Recife, Brazil. The Guiana extended spectrum beta-lactamase (GES) enzymes are responsible for conferring broad spectrum resistance to beta-lactam drugs, including the carbapenems. METHODS: A total of 100 carbapenem-resistant P. aeruginosa isolates underwent polymerase chain reaction (PCR) testing to identify bla GES, bla KPC, bla SPM-1, bla IMP, and bla VIM. Additionally, PCR products positive for bla GES were sequenced. The clonal profiles of these same isolates were then determined by means of enterobacterial repetitive intergenic consensus (ERIC)-PCR analysis. RESULTS: PCR analysis revealed that four isolates harbored bla GES; DNA sequencing showed that two harbored bla GES-1 and two bla GES-11. Beta-lactamase genes bla SPM-1, bla IMP, bla VIM, and bla KPC were investigated; none of these genes was detected. Automated susceptibility testing methods (Vitek®2, bioMérieux) showed that the bla GES-1-positive isolates were only susceptible to polymyxin B. The patterns obtained with ERIC-PCR methods showed clonal relationship between the two isolates that harbored bla GES-11, whereas different clonal profiles were found in the isolates harboring bla GES-1. CONCLUSIONS: We detected the presence of bacterial isolates positive for two different variants of the enzyme GES in three different hospitals from Recife, Brazil. These enzymes have a great capacity for dissemination among Gram-negative bacteria and confer broad-spectrum resistance to beta-lactam antibiotics and to the carbapenems.


Subject(s)
Humans , Pseudomonas aeruginosa/genetics , beta-Lactamases/genetics , Drug Resistance, Multiple, Bacterial/genetics , Anti-Bacterial Agents/pharmacology , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/enzymology , beta-Lactamases/drug effects , Brazil , Base Sequence , Microbial Sensitivity Tests , Polymerase Chain Reaction , Sequence Analysis, DNA , Drug Resistance, Multiple, Bacterial/drug effects
12.
Mem. Inst. Oswaldo Cruz ; 112(10): 723-727, Oct. 2017. tab, graf
Article in English | LILACS | ID: biblio-1040561

ABSTRACT

The development of carbapenem-resistant Acinetobacter species is of serious concern in the hospital settings and naturally occurring oxacillinase genes (blaOXA) have been identified in several Acinetobacter species. In this study, we report the genome sequence of A. pittii TCM178 belongs to ST950, a multidrug-resistant isolate that harbored the blaOXA-72 and blaOXA-533 genes simultaneous. The genome size was estimated to be 3,789,564 bp with 3,501 predicted coding regions, and G+C content is 37.60%. Our findings have raised awareness of the possible constitution of a reservoir for peculiar carbapenemase genes in A. pittii that may spread among other Acinetobacter species in China.


Subject(s)
Humans , Bacterial Proteins/genetics , Acinetobacter/drug effects , Acinetobacter/enzymology , beta-Lactamases/genetics , Genome, Bacterial/genetics , Drug Resistance, Multiple, Bacterial/genetics , Acinetobacter/classification , Base Sequence , China , Sequence Analysis, DNA
13.
Rev. Soc. Bras. Med. Trop ; 50(3): 315-320, May-June 2017. tab
Article in English | LILACS | ID: biblio-896964

ABSTRACT

Abstract INTRODUCTION: Pseudomonas aeruginosa is one of the most common nosocomial pathogens. The emergence of extended spectrum β-lactamases (ESBLs) has been increasingly reported as a major clinical concern worldwide. The main aim of the present study was to determine the distribution of bla OXA, bla PER-1, bla VEB-1, and bla GES-1 genes among ESBL-producing P. aeruginosa isolated from two distinct provinces in Iran. METHODS: In this study, a total of 75 (27.5%) ESBL-producing isolates were identified from 273 P. aeruginosa isolates collected from patients in Qazvin and Tehran. Phenotypic detection of ESBLs and antimicrobial susceptibility testing were performed according to the Clinical and Laboratory Standards Institute guidelines. PCR and sequencing were employed to detect bla OXA-1, bla OXA, bla GES-1, bla PER-1, and bla VEB-1 genes. Isolate genetic relationships were evaluated by repetitive extragenic palindromic sequence-based PCR (REP-PCR). RESULTS: In total, 59 (78.7%) of the ESBL-producing isolates showed multidrug resistance. The highest rates of susceptibility were observed against colistin (75 isolates, 100%) and polymyxin B (75, 100%) followed by amikacin (44, 58.7%), and piperacillin-tazobactam (40, 53.3%). The bla OXA-1 (37.3%) gene was the most common of the genes investigated, followed by bla OXA-4 (32%), bla GES-1 (16%), and bla VEB-1 (13.3%). REP-PCR identified three different genotypes: types A (89.3%), B (6.7%), and C (4%). CONCLUSIONS: We found a significant presence of bla OXA-1, bla OXA-4, bla GES-1, and bla VEB-1 genes among P. aeruginosa isolates, highlighting the need for suitable infection control strategies to effectively treat patients and prevent the further distribution of these resistant organisms.


Subject(s)
Humans , Male , Female , Pseudomonas aeruginosa/genetics , beta-Lactamases/genetics , Drug Resistance, Multiple, Bacterial/genetics , Anti-Bacterial Agents/pharmacology , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/enzymology , Microbial Sensitivity Tests , Polymerase Chain Reaction , Escherichia coli Proteins/genetics , Genes, Bacterial , Genotype , Iran
14.
Mem. Inst. Oswaldo Cruz ; 112(6): 396-403, June 2017. tab
Article in English | LILACS | ID: biblio-841801

ABSTRACT

BACKGROUND To cope with the emergence of multidrug-resistant tuberculosis (MDR-TB), new molecular methods that can routinely be used to screen for a wide range of drug resistance related genetic markers in the Mycobacterium tuberculosis genome are urgently needed. OBJECTIVE To evaluate the performance of multiplex ligaton-dependent probe amplification (MLPA) against Genotype® MTBDRplus to detect resistance to isoniazid (INHr) and rifampicin (RIFr). METHOD 96 culture isolates characterised for identification, drug susceptibility testing (DST) and sequencing of rpoB, katG, and inhA genes were evaluated by the MLPA and Genotype®MTBDRplus assays. RESULTS With sequencing as a reference standard, sensitivity (SE) to detect INHr was 92.8% and 85.7%, and specificity (SP) was 100% and 97.5%, for MLPA and Genotype®MTBDRplus, respectively. In relation to RIFr, SE was 87.5% and 100%, and SP was 100% and 98.8%, respectively. Kappa value was identical between Genotype®MTBDRplus and MLPA compared with the standard DST and sequencing for detection of INHr [0.83 (0.75-0.91)] and RIFr [0.93 (0.88-0.98)]. CONCLUSION Compared to Genotype®MTBDRplus, MLPA showed similar sensitivity to detect INH and RIF resistance. The results obtained by the MLPA and Genotype®MTBDRplus assays indicate that both molecular tests can be used for the rapid detection of drug-resistant TB with high accuracy. MLPA has the added value of providing information on the circulating M. tuberculosis lineages.


Subject(s)
Humans , DNA, Bacterial/genetics , Tuberculosis, Multidrug-Resistant/microbiology , Drug Resistance, Multiple, Bacterial/drug effects , Drug Resistance, Multiple, Bacterial/genetics , Isoniazid/pharmacology , Antibiotics, Antitubercular/pharmacology , Mycobacterium tuberculosis/drug effects , Mycobacterium tuberculosis/genetics , Drug Resistance , Anti-Bacterial Agents
15.
Rev. Soc. Bras. Med. Trop ; 49(4): 441-445, July-Aug. 2016. tab, graf
Article in English | LILACS | ID: lil-792801

ABSTRACT

Abstract: INTRODUCTION: Extended-spectrum beta-lactamases (ESBLs) are bacterial enzymes capable of hydrolyzing beta-lactams. The aim of this study was to describe the prevalence of TEM- and SHV-type ESBL-producing Klebsiella pneumoniae strains in Zahedan, Southeast Iran. METHODS: A total of 170 non-repetitive K. pneumoniae strains were collected from patients referred to three teaching hospitals of Zahedan. Antibiotic susceptibility testing was determined for 17 antibiotics using the Kirby-Bauer disc diffusion method. The frequency of ESBL-producing strains was calculated, and minimum inhibitory concentrations of ESBL-producing strains were determined for cefotaxime, ceftazidime, ceftriaxone, and cefpodoxime. The presence of bla TEM and bla SHV genes was tested in all ESBL-producing strains using polymerase chain reaction and DNA sequencing. RESULTS: Among the 170 K. pneumoniae clinical isolates, 55 (32.4%) were ESBL producers; 92.7% (n=51) and 72.7% (n=40) of the isolates carried the bla SHV and bla TEM genes, respectively, and 67.3% (n=37) carried both genes. The sequencing results showed that all bla TEM types were bla TEM-1, except for two isolates that were bla TEM-104. The bla SHV types were bla SHV-1, bla SHV-11, bla SHV-12, bla SHV-99, bla SHV-108, and bla SHV-110. CONCLUSIONS: The percentage of bla TEM and bla SHV among ESBL-producing K. pneumoniae isolates from Zahedan is relatively high, indicating the need for further surveillance and consideration in antibiotic use. To the best of our knowledge, this is the first report of TEM-104-, SHV-99-, SHV-108-, and SHV-110-type ESBLs among clinical isolates of K. pneumoniae from Iran, and TEM-1, SHV-1, SHV-11, and SHV-12 appear to be the dominant ESBLs in this region.


Subject(s)
Humans , Bacterial Proteins/genetics , beta-Lactamases/biosynthesis , DNA, Bacterial/genetics , Klebsiella pneumoniae/drug effects , Klebsiella pneumoniae/genetics , Anti-Bacterial Agents/pharmacology , Phenotype , Klebsiella Infections/microbiology , Sequence Analysis, DNA , Drug Resistance, Multiple, Bacterial/genetics , Disk Diffusion Antimicrobial Tests , Genes, Bacterial , Genotype , Iran
16.
Braz. j. infect. dis ; 20(3): 276-281, May.-June 2016. tab, graf
Article in English | LILACS | ID: lil-789481

ABSTRACT

Abstract Introduction There is a mechanism of macrolide resistance in Staphylococcus spp. which also affects the lincosamides and type B streptogramins characterizing the so-called MLSB resistance, whose expression can be constitutive (cMLSB) or inducible (iMLSB) and is encoded mainly by ermA and ermC genes. The cMLSB resistance is easily detected by susceptibility testing used in the laboratory routine, but iMLSB resistance is not. Therapy with clindamycin in cases of infection with isolated iMLSB resistance may fail. Objective To characterize the phenotypic (occurrence of cMLSB and iMLSB phenotypes) and molecular (occurrence of ermA and ermC genes) profiles of MLSB resistance of clinical isolates of susceptible and methicillin-resistant Staphylococcus aureus and CNS (coagulase-negative Staphylococcus) from patients of a university hospital, in Pernambuco. Methods The antimicrobial susceptibility of 103 isolates was determined by the disk diffusion technique in Mueller–Hinton agar followed by oxacillin screening. The iMLSB phenotype was detected by D test. Isolates with cMLSB and iMLSB phenotypes were subjected to polymerase chain reaction (PCR) for the detection of ermA and ermC genes. Results The cMLSB and iMLSB phenotypes were respectively identified in 39 (37.9%) and five (4.9%) isolates. The iMLSB phenotype was found only in four (10.8%) methicillin-susceptible S. aureus and one (4.5%) methicillin-resistant S. aureus. In the 44 isolates subjected to PCR, four (9.1%) only ermA gene was detected, a lower frequency when compared to only ermC 17 (38.6%) gene and to one (2.3%) isolate presenting both genes. Conclusion In the Staphylococcus spp. analyzed, the ermC gene was found more often than the ermA, although the iMLSB phenotype had been less frequent than the cMLSB. It was important to perform the D test for its detection to guide therapeutic approaches.


Subject(s)
Humans , Staphylococcus/drug effects , Staphylococcus/genetics , Macrolides/pharmacology , Streptogramin B/pharmacology , Drug Resistance, Multiple, Bacterial/genetics , Lincosamides/pharmacology , Phenotype , Brazil , Drug Resistance, Multiple, Bacterial/drug effects , Disk Diffusion Antimicrobial Tests , Genes, Bacterial/genetics , Hospitals, University
17.
Mem. Inst. Oswaldo Cruz ; 111(5): 355-358, May 2016. tab, graf
Article in English | LILACS | ID: lil-782052

ABSTRACT

Acinetobacter baumannii, a strictly aerobic, non-fermentative, Gram-negative coccobacillary rod-shaped bacterium, is an opportunistic pathogen in humans. We recently isolated a multidrug-resistant A. baumannii strain KBN10P02143 from the pus sample drawn from a surgical patient in South Korea. We report the complete genome of this strain, which consists of 4,139,396 bp (G + C content, 39.08%) with 3,868 protein-coding genes, 73 tRNAs and six rRNA operons. Identification of the genes related to multidrug resistance from this genome and the discovery of a novel conjugative plasmid will increase our understanding of the pathogenicity associated with this species.


Subject(s)
Humans , Acinetobacter baumannii/genetics , Drug Resistance, Multiple, Bacterial/genetics , Genome, Bacterial/genetics , Acinetobacter baumannii/isolation & purification , Acinetobacter Infections/microbiology , DNA, Bacterial/genetics , Republic of Korea , Sequence Analysis, DNA
18.
Braz. j. infect. dis ; 20(2): 166-172, Mar.-Apr. 2016. tab, graf
Article in English | LILACS | ID: lil-780813

ABSTRACT

Abstract Multidrug-resistant tuberculosis (MDRTB) is a serious world health problem that limits public actions to control tuberculosis, because the most used anti-tuberculosis first-line drugs fail to stop mycobacterium spread. Consequently, a quick detection through molecular diagnosis is essential to reduce morbidity and medical costs. Despite the availability of several molecular-based commercial-kits to diagnose multidrug-resistant tuberculosis, their diagnostic value might diverge worldwide since Mycobacterium tuberculosis genetic variability differs according to geographic location. Here, we studied the predictive value of four common mycobacterial mutations in strains isolated from endemic areas of Brazil. Mutations were found at the frequency of 41.9% for katG, 25.6% for inhA, and 69.8% for rpoB genes in multidrug-resistant strains. Multimarker analysis revealed that combination of only two mutations (“katG/S315T + rpoB/S531L”) was a better surrogate of multidrug-resistant tuberculosis than single-marker analysis (86% sensitivity vs. 62.8%). Prediction of multidrug-resistant tuberculosis was not improved by adding a third or fourth mutation in the model. Therefore, rather than using diagnostic kits detecting several mutations, we propose a simple dual-marker panel to detect multidrug-resistant tuberculosis, with 86% sensitivity and 100% specificity. In conclusion, this approach (previous genetic study + analysis of only prevalent markers) would considerably decrease the processing costs while retaining diagnostic accuracy.


Subject(s)
Humans , Bacterial Proteins/genetics , DNA-Directed RNA Polymerases/genetics , Catalase/genetics , Drug Resistance, Multiple, Bacterial/genetics , Isoniazid/pharmacology , Antitubercular Agents/pharmacology , Rifampin/pharmacology , DNA, Bacterial , Microbial Sensitivity Tests , Genetic Markers , Polymerase Chain Reaction , Predictive Value of Tests , Sensitivity and Specificity , Tuberculosis, Multidrug-Resistant/microbiology , Genotype , Mutation/genetics , Mycobacterium tuberculosis/drug effects , Mycobacterium tuberculosis/genetics
19.
Mem. Inst. Oswaldo Cruz ; 111(3): 155-160, Mar. 2016. tab, graf
Article in English | LILACS | ID: lil-777372

ABSTRACT

Coagulase-negative staphylococci, particularly Staphylococcus epidermidis, can be regarded as potential reservoirs of resistance genes for pathogenic strains, e.g., Staphylococcus aureus. The aim of this study was to assess the prevalence of different resistance phenotypes to macrolide, lincosamide, and streptogramins B (MLSB) antibiotics among erythromycin-resistant S. epidermidis, together with the evaluation of genes promoting the following different types of MLSB resistance:ermA, ermB, ermC,msrA, mphC, and linA/A’. Susceptibility to spiramycin was also examined. Among 75 erythromycin-resistantS. epidermidis isolates, the most frequent phenotypes were macrolides and streptogramins B (MSB) and constitutive MLSB (cMLSB). Moreover, all strains with the cMLSB phenotype and the majority of inducible MLSB (iMLSB) isolates were resistant to spiramycin, whereas strains with the MSB phenotype were sensitive to this antibiotic. The D-shape zone of inhibition around the clindamycin disc near the spiramycin disc was found for some spiramycin-resistant strains with the iMLSB phenotype, suggesting an induction of resistance to clindamycin by this 16-membered macrolide. The most frequently isolated gene was ermC, irrespective of the MLSB resistance phenotype, whereas the most often noted gene combination wasermC, mphC, linA/A’. The results obtained showed that the genes responsible for different mechanisms of MLSB resistance in S. epidermidis generally coexist, often without the phenotypic expression of each of them.


Subject(s)
Humans , Drug Resistance, Multiple, Bacterial/genetics , Genotype , Lincosamides/pharmacology , Macrolides/pharmacology , Staphylococcus epidermidis/drug effects , Staphylococcus epidermidis/genetics , Streptogramin Group B/pharmacology , Clindamycin/pharmacology , Disk Diffusion Antimicrobial Tests , Erythromycin/pharmacology , Genetic Testing/methods , Lincomycin/pharmacology , Phenotype , Polymerase Chain Reaction , Prevalence , Spiramycin/pharmacology , Staphylococcus epidermidis/isolation & purification
20.
Acta cir. bras ; 31(3): 206-211, Mar. 2016. tab, graf
Article in English | LILACS | ID: lil-777090

ABSTRACT

ABSTRACT PURPOSE: To determine the genetic diversity of MDR P. aeruginosa strains isolated from burn and wound infections in Ahvaz, Iran, by ERIC-PCR. METHODS: From total 99 strains of P. aeruginosa defined as MDR by using drug susceptibility testing, 66 were subjected to ERIC-PCR analysis, comprises 53 strains isolated from burn infection, and 13 randomly selected strains from wound infection with higher resistance to combinations of more numbers of drugs. RESULTS: Eight clusters (I to VIII), and 50 single clones were generated for tested MDR isolates analyzed by ERIC-PCR. The high heterogeneity was observed among the isolates from burn infections including 16 isolates which were categorized in eight clusters and 37 single clones. The isolates in clusters II, III, VI, VIII showed 100% similarity. CONCLUSIONS: The high level of genotypic heterogeneity in P. aeruginosa strains demonstrated no genetic correlation between them. Extremely high drug resistance in isolates from burn, suggests that efficient control measures and proper antibiotic policy should be observed.


Subject(s)
Humans , Pseudomonas aeruginosa/genetics , Pseudomonas Infections/microbiology , Wound Infection/microbiology , Burns/microbiology , DNA, Bacterial/genetics , Drug Resistance, Multiple, Bacterial/genetics , Pseudomonas aeruginosa/isolation & purification , Repetitive Sequences, Nucleic Acid/genetics , Polymerase Chain Reaction , Genotype
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