Genotypes of Mycobacterium tuberculosis in patients at risk of drug resistance in Bolivia.

Bolivia ranks among the 10 Latin American countries with the highest rates of tuberculosis (TB) and multidrug resistant (MDR) TB. In view of this, and of the lacking information on the population structure of Mycobacterium tuberculosis in the country, we explored genotype associations with drug resistance and clustering by analyzing isolates collected in 2010 from 100 consecutive TB patients at risk of drug resistance in seven of the nine departments in which Bolivia is divided. Fourteen isolates were MDR, 29 had other drug resistance profiles, and 57 were pansusceptible. Spoligotype family distribution was: Haarlem 39.4%, LAM 26.3%, T 22.2%, S 2.0%, X 1.0%, orphan 9.1%, with very low intra-family diversity and absence of Beijing genotypes. We found 66 different MIRU-VNTR patterns; the most frequent corresponded to Multiple Locus Variable Analysis (MLVA) MtbC15 patterns 860, 372 and 873. Twelve clusters, each with identical MIRU-VNTR and spoligotypes, gathered 35 patients. We found no association of genotype with drug resistant or MDR-TB. Clustering associated with SIT 50 and the H3 subfamily to which it belongs (p<0.0001). The largest cluster involved isolates from three departments and displayed a genotype (SIT 50/MLVA 860) previously identified in Bolivian migrants into Spain and Argentina suggesting that this genotype is widespread among Bolivian patients. Our study presents a first overview of M. tuberculosis genotypes at risk of drug resistance circulating in Bolivia. However, results should be taken cautiously because the sample is small and includes a particular subset of M. tuberculosis population.

Detección de mutaciones en los Genes rpoß y katG asociados a resistencia en cepas de Mycobacterium tuberculosis de Bolivia / Detection of mutations in rpoß and katG genes associated to resistance in Mycobacterium tuberculosis strains from Bolivia

Objetivo: Evaluar la sensibilidad y especificidad de la genotipificación, como instrumento de diagnóstico rápido y confiable parala detección de mutaciones en los genes rpoß y katG asociados a resistencia,en cepas de Mycobacterium tuberculosis de Bolivia.Diseño: Test Diagnóstico Metodología: Las cepas analizadas fueron aisladas y enviadas por los diferentes Laboratorios de la Red Nacional de Diagnósticode Tuberculosis de Bolivia entre febrero y diciembre de 2007. La muestra para el presente estudio estuvo constituida por un totalde 65 aislamientos previamente caracterizados por métodos fenotípicos de cultivo y pruebas de sensibilidad a la RIF e INH, porel método de las proporciones Canetti-Rist. La genotipificación ha sido realizada utilizando el kit Genotype MTBDR, basado enla utilización de métodos de amplificación e hibridización, para detectar mutaciones a nivel de los marcadores de resistencia rpoßy katG.Resultados: Se procedió al cálculo de la sensibilidad y especificidad de la prueba de diagnóstico; además de los valores predictivospositivo y negativo. Dicho análisis muestra los siguientes resultados: sensibilidad 74...

Objective:To evaluate the sensitivity and specificity of genotyping as a tool for rapid and reliable detection of mutations in rpoß and katG genes associated with resistance in Mycobacterium tuberculosisstrains from Bolivia. Design:Diagnostic Test Methodology: The strains analyzed were isolated and submitted by different laboratories of the National Network for Diagnosisof Tuberculosis of Bolivia between February and December 2007. The sample for this study consisted of 65 isolates previousl y characterized by phenotypic methods of culture and sensitivity testing to RIF and INH by the Canetti-Rist proportion method. Genotyping of these samples has been done using the MTBDR Genotype kit, according to amplification and hybridization methodsto detect mutations at the rpoß and katG resistance markers.Results:The sensitivity and specificity of the diagnostic tests were calculated, as well as the positive and negative predictivevalues. This analysis shows the following results: sensitivity 74%, specificity 92%, positive predictive value 92%, and negative predictive value 73%. Conclusions: The genotyping test using Genotype MTBDR, meeting validation criteria for a diagnostic test study in our country,constitutes a quick, useful and reliable tool for use in diagnosis and routine determination of sensitivity and resistance in MTBCstrains.

Resazurin microtiter assay plate testing of Mycobacterium tuberculosis susceptibilities to second-line drugs: rapid, simple, and inexpensive method.

The emergence of multidrug-resistant tuberculosis calls for new, rapid drug susceptibility tests. We have tested 150 Mycobacterium tuberculosis isolates against the second-line drugs ethionamide, kanamycin, capreomycin, ofloxacin, and para-aminosalicylic acid by the colorimetric resazurin microtiter assay and the proportion method. By visual reading, MICs were obtained after 8 days. A very good correlation between results by the colorimetric resazurin microtiter assay and the proportion method was obtained. The colorimetric resazurin microtiter assay is inexpensive, rapid, and simple to perform, and implementation of the assay is feasible for low-resource countries.

Resazurin microtiter assay plate: simple and inexpensive method for detection of drug resistance in Mycobacterium tuberculosis.

A method for detecting multidrug-resistant Mycobacterium tuberculosis by using a reduction of resazurin is described. Eighty clinical isolates were evaluated against isoniazid and rifampin; results at 7 days were compared with those of the proportion method. Specificity and sensitivity were excellent. The method is simple, inexpensive, and rapid and might be used with other antituberculosis drugs.

Octavo seminario de evaluación del servicio nacional de control de la tuberculosis del 14 y 15 de mayo de 1998: Huatajata La Paz-Bolivia

La Dirección General de Epidemiología y el Servicio de Control de Tuberculosis, vio necesario realizar el presente Seminario de Evaluación no solo para fortalecer a los Servicios Departamentales, en su capacidad analítica de sus realidades epidemiológicas así como en el intercambio de experiencias locales para la elaboración de estrategias, si no además para la actualización en las normas y procedimientos del servicio, fundamentalmente referidos a la localización de casos y tratamiento de los mismos. Asimismo, este documento pretende mejorar la eficiencia en el control de la tuberculosis en Bolivia para alcanzar las metas nacionales e internacionales para el año 2000 de: Detectar al 70 de las fuentes de infección existentes en la comunidad y curar al 85 de las mismas.

Tenosinovitis tuberculosa a proposito de un caso / Tuberculous tenosynovitis. Report of a case

Presentamos un nino de 11 anos de edad con el diagnostico de tenosinovitis tuberculosa, que fue internado en el Hospital de Ninos "Ovidio Aliaga Uria" de la Ciudad de La Paz por presentar uan tumoracion indolora del pie derecho de 3 meses de evolucion. Los estudios bacteriologicos anatomopatologicos confirmaron el idagnostico de tuberculosis. El paciente respondio adecuadamente al tratamiento quirurgico y medico especifico. Se presenta el caso por ser una forma excepcional y rara de tuberculosis.