a multicenter study

(1) Background: The Commercial Kit SIRE Nitratase® PlastLabor, is a drug susceptibility test kit used to detect Mycobacterium tuberculosis resistance to first-line TB treatment drugs. The present study aimed at evaluating its performance in a multicenter study. (2) Methods: To determine its accuracy, the proportion methods in Lowenstein Jensen medium or the BACTECTMMGITTM960 system was used as a gold standard. (3) Results: The study revealed that the respective accuracies of the kit with 190 M. tuberculosis clinical isolates, using the proportion methods in Lowenstein Jensen medium or BACTECTMMGITTM960 system as a gold standard, were 93.9% and 94.6%, 96.9% and 94.6%, 98.0% and 97.8%, and 98.0% and 98.9%, for streptomycin, isoniazid, rifampicin, and ethambutol, respectively. (4) Conclusion: Thus, the kit can rapidly screen resistance to streptomycin, isoniazid, rifampicin, and ethambutol. Additionally, it does not require sophisticated equipment; hence, it can be easily used in the laboratories of low and middle income countries.publishersversionpublishe

Rapid Diagnosis of resistance of mycobacterium tuberculosis to rifampicin and isoniazid by the nitrate reductase method

Submitted by Repositório Arca ([email protected]) on 2019-07-04T18:43:55Z No. of bitstreams: 2 license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) reginalda_ferreira_de_melo.pdf: 1587787 bytes, checksum: 6d1fc950578de3bc42007ada33023ec1 (MD5)Approved for entry into archive by Erasmo Martins ([email protected]) on 2019-07-17T15:43:42Z (GMT) No. of bitstreams: 2 reginalda_ferreira_de_melo.pdf: 1587787 bytes, checksum: 6d1fc950578de3bc42007ada33023ec1 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5)Made available in DSpace on 2019-07-17T15:43:42Z (GMT). No. of bitstreams: 2 reginalda_ferreira_de_melo.pdf: 1587787 bytes, checksum: 6d1fc950578de3bc42007ada33023ec1 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2016Fundação Oswaldo Cruz. Escola Nacional de Saúde Pública Sergio Arouca. Rio de Janeiro, RJ, Brasil.A tuberculose (TB) permanence entre as doenças infecciosas que mais acometem a humanidade, sendo considerada como problema de saúde pública de relevância mundial. Nosso estudo consiste em diagnosticar com rapidez cepas de M. tuberculosis resistentes à rifampicina e isoniazida por meio de nitrato redutase (NRA), o que seria de grande importância para o início do tratamento, contribuindo para a quebra da cadeia de transmissão dos casos de tuberculose multirreresistentes (TB-MDR). Para este estudo foi utilizada 140 cepas de M. tuberculosis, pertencentes ao acervo do CRPHF, para avaliar a sensibilidade e especificidade do método NRA comparando com os padrões ouro: Método das Proporções (MP) e Sistema Automatizado MGIT 960. De acordo com os resultados obtidos, comparando-se ao MP, detectou-se que o teste de NRA apresentou 99 % de sensibilidade e 100% de especificidade para detecção da resistência à INH. Já para a detecção da resistência à RMP o teste de RNA apresentou 95% de sensibilidade e 98% de especificidade. Os valores preditivos positivos foram de 99% e 100% para RMP e INH. Os valores preditivos negativos foram de 94% e 98% para RMP e INH. Comparando com os resultados do Sistema MGIT 960, nosso estudo mostrou que o teste de NRA apresentou 94% de sensibilidade e 93% de especificidade para a detecção da resistência a INH. Já para a detecção da resistência à RMP o NRA apresentou 95% de sensibilidade e 97 % de especificidade. Os valores preditivos positivos foram de 97% e 95% para RMP e INHA. Os valores preditivos negativos foram de 94% e 91% para RMP e INH. Foi observada uma excelente concordância entre os métodos de testes fenotípicos comparando-os a NRA com MP: 93% e 99% para RMP e INH. Comparando NRA com MGIT: 91% e 87% para RMP e INH. Nas despesas de custeio de 140 testes, a NRA gastou R$177,80 e o MGIT 960 gastou R$ 2.640,00. Os testes de MGIT 960 foram aproximadamente 138 vezes mais caros do que os testes de NRA. O tempo dos resultados foram semelhante nas duas metodologias, uma média de 10 dias para NRA (84,2% dos testes) e MGIT 960 (83,5% dos testes). A redução do tempo e dos custeios na utilização deste método poderá se tornar uma ferramenta importante no programa de controle da tuberculose, principalmente na detecção de cepas de multirresistentes.Tuberculosis (TB) remains as one of the infectious diseases with the biggest burden on mankind, being considered as a worldwide public health concern. The goal of our study was to quickly identify M. tuberculosis strains resistant to isoniazid (INH) and rifampicin (RMP) through the NRA. Such assay would be extremely valuable for the control of TB, given that treatment could be initiated sooner and the transmission chain of the organism would be interrupted. Thus, we used 140 isolates from the strain collection of the National Reference Laboratory for Tuberculosis to evaluate the sensitivity and specificity of the NRA when compared to the gold standard, the method of proportion (MP), and the automated MGIT 960 system. Our results showed that, compared to the MP, the NRA presented a sensitivity of 99% and specificity of 100% for the detection of INH resistance. For RMP resistance, the NRA showed a sensitivity of 95% and specificity of 98%. The positive predictive values showed 99 % and 100% for INH and RMP. The negative predictive values showed 94% and 98% to RIF and INH. Compared to MGIT 960, the NRA showed 94% of sensitivity and 93% of specificity for the detection of INH resistance. For the detection of RMP resistance, the NRA showed 95% of sensitivity and 97% of specificity. The positive predictive values showed 97% and 95% for RMP and INH. The negative predictive values showed 94% and 91% for RIF and INH. Comparing the phenotypic tests was observed an excellent agreement between the methods: the NRA with MP, 93% and 99% for RIF and INH. Comparing the NRA with MGIT: 91% and 87% for RIF and INH. In costing expenses for 140 tests NRA spent R$177,80 and MGIT 960 spent R$ 2.640,00. The MGIT 960 tests were approximately 138 more expensive than the NRA tests. The time results of the two methods were similar, averaging 10 days for NRA (84.2% of the tests) and 960 MGIT (83.5% of the tests). The reduction in time to diagnosis achieved by this method may become an important tool in the control of tuberculosis in high-burden countries

SHORT COMMUNICATION - Direct Sensitivity Test of the MB/BacT System

In order to evaluate the direct-method test of sensitivity to drugs used in the principal tuberculosis treatment regimes, in the Organon Teknika MB/BacT system, we tested 50 sputum samples positive to microscopy taken from patients with pulmonary tuberculosis and with clinical indications for an antibiogram, admitted sequentially for examination during the routine of the reference laboratory. The material was treated v/v with 23% trisodium phosphate solution, incubated for 24 h at 35°C, and neutralized v/v with 20% monosodium phosphate solution. The material was then centrifuged and the sediment inoculated into flasks containing Rifampin - 2 μg/ml, Isoniazid - 0.2 μg/ml, Pyrazinamide - 100 μg/ml, Ethambutol - 2.5 μg/ml, Ethionamide - 1.25 μg/ml, and Streptomycin - 2 μg/ml. The tests were evaluated using the indirect method in the BACTEC 460 TB (Becton Dickinson) system as the gold standard. The results showed that the Rifampin test performed best, i.e., 100% sensitivity at 95% Confidence Interval (82.2-100) and 100% specificity at 95% Confidence Interval (84.5-100), followed by Isoniazid and Pyrazinamide. In this experiment, 92% of the materials showed a final reading in 30 days; this period represents the time for primary isolation as well as the results of the sensitivity profile, and is within Centers for Disease Control and Prevention recommendations regarding time for performance of the antibiogram. The inoculated flasks showed no contamination during the experiment. The MB/BacT is shown to be a reliable, rapid, fully automated nonradiometric system for the tuberculosis antibiogram

Evaluation of indirect susceptibility testing of Mycobacterium tuberculosis to the first- and second-line, and alternative drugs by the newer MB/BacT system

In order to evaluate the Organon Teknika MB/BacT system used for testing indirect susceptibility to the alternative drugs ofloxacin (OFLO), amikacin (AMI), and rifabutin (RIF), and to the usual drugs of standard treatment regimes such as rifampin (RMP), isoniazid (INH), pyrazinamide (PZA), streptomycin (SM), ethambutol (EMB), and ethionamide (ETH), cultures of clinical specimens from 117 patients with pulmonary tuberculosis under multidrug-resistant investigation, admitted sequentially for examination from 2001 to 2002, were studied. Fifty of the Mycobacterium tuberculosis cultures were inoculated into the gold-standard BACTEC 460 TB (Becton Dickinson) for studying resistance to AMI, RIF, and OFLO, and the remaining 67 were inoculated into Lowenstein Jensen (LJ) medium (the gold standard currently used in Brazil) for studying resistance to RMP, INH, PZA, SM, EMB, and ETH. We observed 100% sensitivity for AMI (80.8-100), RIF (80.8-100), and OFLO (78.1-100); and 100% specificity for AMI (85.4-100), RIF (85.4-100), and OFLO (86.7-100) compared to the BACTEC system. Comparing the results obtained in LJ we observed 100% sensitivity for RMP (80-100), followed by INH - 95% (81.8-99.1), EMB - 94.7% (71.9-99.7), and 100% specificity for all drugs tested except for PZA - 98.3 (89.5-99.9) at 95% confidence interval. The results showed a high level of accuracy and demonstrated that the fully automated, non-radiometric MB/BacT system is indicated for routine use in susceptibility testing in public health laboratories

Direct Sensitivity Test of the MB/BacT System

In order to evaluate the direct-method test of sensitivity to drugs used in the principal tuberculosis treatment regimes, in the Organon Teknika MB/BacT system, we tested 50 sputum samples positive to microscopy taken from patients with pulmonary tuberculosis and with clinical indications for an antibiogram, admitted sequentially for examination during the routine of the reference laboratory. The material was treated v/v with 23% trisodium phosphate solution, incubated for 24 h at 35°C, and neutralized v/v with 20% monosodium phosphate solution. The material was then centrifuged and the sediment inoculated into flasks containing Rifampin - 2 µg/ml, Isoniazid - 0.2 µg/ml, Pyrazinamide - 100 µg/ml, Ethambutol - 2.5 µg/ml, Ethionamide - 1.25 µg/ml, and Streptomycin - 2 µg/ml. The tests were evaluated using the indirect method in the BACTEC 460 TB (Becton Dickinson) system as the gold standard. The results showed that the Rifampin test performed best, i.e., 100% sensitivity at 95% Confidence Interval (82.2-100) and 100% specificity at 95% Confidence Interval (84.5-100), followed by Isoniazid and Pyrazinamide. In this experiment, 92% of the materials showed a final reading in 30 days; this period represents the time for primary isolation as well as the results of the sensitivity profile, and is within Centers for Disease Control and Prevention recommendations regarding time for performance of the antibiogram. The inoculated flasks showed no contamination during the experiment. The MB/BacT is shown to be a reliable, rapid, fully automated nonradiometric system for the tuberculosis antibiogram

Detection of drug resistant Mycobacterium Tuberculosis strains using kit SIRE Nitratase®: a multicenter study

This research was funded by MINAS GERAIS STATE RESEARCH SUPPORT FOUNDATION (FAPEMIG), grants numbers 65/10 and CDS-APQ-03266-13, and by NATIONAL COUNCIL FOR SCIENTIFIC AND TECHNOLOGICAL DEVELOPMENT (CNPQ) grants numbers 310174/2014-7 and 446796/2014-0.Federal University of Minas Gerais. Faculty of Medicine. Mycobacteria Research Laboratory. Belo Horizonte, MG, Brazil.Federal University of Minas Gerais. Faculty of Medicine. Mycobacteria Research Laboratory. Belo Horizonte, MG, Brazil.Federal University of Minas Gerais. Faculty of Medicine. Mycobacteria Research Laboratory. Belo Horizonte, MG, Brazil.Federal University of Minas Gerais. Faculty of Medicine. Mycobacteria Research Laboratory. Belo Horizonte, MG, Brazil.Federal University of Minas Gerais. Faculty of Pharmacy. Department of Social Pharmacy. Belo Horizonte, MG, Brazil.Federal University of Minas Gerais. Veterinary School. Department of Preventive Veterinary Medicine. Belo Horizonte, MG, Brazil.Federal University of Rio Grande. Faculty of Medicine. Laboratory of Mycobacteria. Rio Grande, RS, Brazil.Federal University of Rio Grande. Faculty of Medicine. Laboratory of Mycobacteria. Rio Grande, RS, Brazil.Federal University of Rio Grande. Faculty of Medicine. Laboratory of Mycobacteria. Rio Grande, RS, Brazil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Tropical Medicine Foundation Dr. Heitor Vieira Dourado. Manaus, AM, Brazil.Tropical Medicine Foundation Dr. Heitor Vieira Dourado. Manaus, AM, Brazil.Federal University of Rio de Janeiro. Institute of Chest Diseases. Clementino Fraga Filho University Hospital. Rio de Janeiro, RJ, Brazil.Federal University of Rio de Janeiro. Institute of Chest Diseases. Clementino Fraga Filho University Hospital. Rio de Janeiro, RJ, Brazil.Federal University of Grande Dourados. Faculty of Health Sciences. Dourados, MS, Brazil / Oswaldo Cruz Foundation. Campo Grande, Mato Grosso do Sul, MS, Brazil.Adolfo Lutz Institute. Bacteriology Center. Tuberculosis and Mycobacteriosis Center. São Paulo, SP, Brazil.Adolfo Lutz Institute. Bacteriology Center. Tuberculosis and Mycobacteriosis Center. São Paulo, SP, Brazil.Adolfo Lutz Institute. Bacteriology Center. Tuberculosis and Mycobacteriosis Center. São Paulo, SP, Brazil.State Secretariat of Health of Rio Grande do Sul. State Center for Health Surveillance. Center for Scientific and Technological Development. Porto Alegre, RS, Brazil.State Secretariat of Health of Rio Grande do Sul. State Center for Health Surveillance. Center for Scientific and Technological Development. Porto Alegre, RS, Brazil.Oswaldo Cruz Foundation. National Institute of Infectology Evandro Chagas. Laboratory of Bacteriology and Bioassays of Rio de Janeiro. Rio de Janeiro, RJ, Brazil.Sergio Arouca National Public Health School. Professor Hélio Fraga Reference Center. Rio de Janeiro, RJ, Brazil.Sergio Arouca National Public Health School. Professor Hélio Fraga Reference Center. Rio de Janeiro, RJ, Brazil.Nova University of Lisbon. Institute of Hygiene and Tropical Medicine. Medical Microbiology Unit, Global Health and Tropical Medicine. Lisboa, Portugal.Nova University of Lisbon. Institute of Hygiene and Tropical Medicine. Medical Microbiology Unit, Global Health and Tropical Medicine. Lisboa, Portugal.Federal University of Rio de Janeiro. Faculty of Medicine. Tuberculosis Research Center. Rio de Janeiro, RJ, Brazil.Background: The Commercial Kit SIRE Nitratase® PlastLabor, is a drug susceptibility test kit used to detect Mycobacterium tuberculosis resistance to first-line TB treatment drugs. The present study aimed at evaluating its performance in a multicenter study. (2) Methods: To determine its accuracy, the proportion methods in Lowenstein Jensen medium or the BACTECTMMGITTM960 system was used as a gold standard. (3) Results: The study revealed that the respective accuracies of the kit with 190 M. tuberculosis clinical isolates, using the proportion methods in Lowenstein Jensen medium or BACTECTMMGITTM960 system as a gold standard, were 93.9% and 94.6%, 96.9% and 94.6%, 98.0% and 97.8%, and 98.0% and 98.9%, for streptomycin, isoniazid, rifampicin, and ethambutol, respectively. (4) Conclusion: Thus, the kit can rapidly screen resistance to streptomycin, isoniazid, rifampicin, and ethambutol. Additionally, it does not require sophisticated equipment; hence, it can be easily used in the laboratories of low and middle income countries