Evaluation of mycobacterium tuberculosis IgG antibody protein chip in patients with active and inactive tuberculosis / 中国生化药物杂志

Objective To explore protein microarray chip diagnostic value for patients with active and inactive tuberculosis.Methods 178 cases of active patients tuberculosis and 79 cases of inactive tuberculosis patients and 92 cases of healthy control using protein microarray chip detection.Results Tuberculosis protein chip had a diagnostic value for tuberculosis and the positive rate is 58.4%; combined the diagnostic value of three kinds of proteins is higher than the diagnostic value of a single protein;16 kD protein of inactive tuberculosis positive rate was 16.4%, better than the positive rate of 3.4% for active tuberculosis (P<0.05).Conclusion Tuberculosis protein chip has a diagnostic value for active tuberculosis and inactive tuberculosis.16 kD protein positive rate more than 38 kD protein in patients with inactive tuberculosis (P<0.05).

A Proposal for Laboratory Workflow Changes for Efficient Tuberculosis Control / 대한임상미생물학회지

There are several problems in mycobacterial detection and drug susceptibility testing. One problem is that some test results are unnecessarily delayed because the tests are postponed until patients revisit clinics and pay the cost of the tests. Another problem is that critical and important tests are not requested because patients do not agree with their necessity. These inefficient practices may be due to the fee-for-service policy that the Korean medical insurance system is adopting and because many test methods used for mycobacterial infection have each test codes. Therefore, we propose a new test code encompassing several test items necessary for laboratory diagnosis of mycobacterial infection. This new code enables all necessary tests to be performed sequentially without delay and also prevents performance of unnecessary tests. These changes will help control tuberculosis without any further medical insurance financial input.

Nuevos métodos para el diagnóstico de la tuberculosis / New methods for the diagnosis of tuberculosis

La magnitud del problema mundial de la tuberculosis y su potencial de incremento han conducido a la necesidad de mejorar los métodos de diagnóstico como una de las estrategias conducentes al control de la enfermedad. Los nuevos métodos incluyen pruebas moleculares para la detección directa, medios de cultivo rápido y novedosos procedimientos de identificación. Para la detección directa de micobacterias se dispone hoy de pruebas basadas en la amplificación de los ácidos nucleicos, cuya sensibilidad supera a la de la baciloscopia y es cercana a la de los cultivos, pero con mayores costos que los procedimientos tradicionales.La automatización para detectar el crecimiento en medios de cultivo produjo un cambio radical en la micobacteriología, pues con ella se logró disminuir considerablemente el tiempo requerido para aislar el M. tuberculosis (MTB); la combinación de métodos de detección rápida permite en la actualidad mejores tasas de aislamiento y la demostración más precoz del crecimiento. Las nuevas alternativas han logrado aumentar tanto la sensibilidad como la especificidad y la rapidez diagnósticas; sin embargo, es necesario mejorar aún más los métodos de diagnóstico de esta enfermedad de modo que se combinen el mejor desempeño y la simplicidad de los procedimientos con la disminución de los costos.

The magnitude of the global tuberculosis problem and its potential for increase have led to efforts to improve the diagnostic methods as one of the leadingcontrol strategies. New diagnostic tools have been developed, including direct detection tests, rapid culture media and identification methods. For the direct detection of mycobacteria, tests based on nucleic acid amplification have been implemented, with higher sensitivity than the direct smear, close to that of the cultures; however, they are still expensive methods. Availability of the automated cultures resulted in a radical change in mycobacteriology, reducing the time required for the isolation ofMycobacterium tuberculosis. The combination of rapid methods has increased the rates of isolation and decreased the time required for the detection of growth. Different tools for identifying mycobacteria have also been developed, aimed at improving theperformance of traditional biochemical methods and achieving species identification in a few hours. The new diagnostic alternatives have succeeded in improving the sensitivity, specificity and speed in the diagnosis of tuberculosis; however, the challengeremains to reduce their cost and to make them more accessible in countries where the problem with this disease is still serious.

Cinco años de experiencia con el agar de capa delgada para el diagnóstico rápido de tuberculosis

La tuberculosis continúa siendo un problema de salud pública en el mundo, principalmente en los países en vía de desarrollo, donde ocurre el 95% de los casos. Estos países no tienen fácil acceso a los métodos de diagnóstico rápido actualmente disponibles, debido al alto costo que tienen. Por tanto, se hace necesario el desarrollo de técnicas rápidas de más bajo costo que sean accesibles a estas regiones. Este trabajo tuvo como objetivo comparar un medio de cultivo rápido y de bajo costo, el agar de capa delgada (CD7H11), con el medio de Lowenstein-Jensen. Para esto se procesaron 1.809 muestras clínicas de pacientes con diagnóstico presuntivo de tuberculosis y que requirieron cultivo. Las muestras se procesaron según los métodos estándar recomendados y se sembraron en ambos medios de cultivo. Se comparó la rapidez para la detección de cultivos positivos y la sensibilidad, la especificidad, los valores predictivos (VPP y VPN) y la concordancia de CD7H11 con respecto al método de referencia. CD7H11 mostró una sensibilidad del 73,5% (IC95%:69,6-80,4) y una especificidad del 99,2% (IC95%: 98,8-99,6), valor predictivo positivo de 90,4% (IC95%: 85,3-95,6) y valor predictivo negativo de 97,6% (IC95%: 96,8-98,3). La concordancia entre los dos métodos fue de 0,52 (coeficiente kappa). CD7H11 tuvo un tiempo promedio para la detección de las micobacterias de 11 días (DE±4,9), frente a 26,5 (DE±8.6) días del LJ. Se obtuvieron resultados similares al comparar las muestras pulmonares y multibacilares. CD7H11 mostró una sensibilidad menor en muestras extrapulmonares, comparada con las pulmonares (65,8; IC95%: 55,1-76,5 vs. 81,0; IC95%: 72,4-89,7). El uso concomitante de los medios de cultivo aumentó la sensibilidad pues 24,1% de las muestras se detectaron sólo por LJ y 7,1% por CD7H11. El medio de capa delgada demostró ser un método rápido de cultivo para micobacterias que es fácilmente accesible a los sistemas de salud de los países en desarrollo, en ...

Five year experience with thin layer agar medium for rapid diagnosis of tuberculosis Tuberculosis represents a public health problem worldwide, mainly in developing countries where 95% of the cases occur. New technologies that support rapid diagnosis are not available in these settings because of high cost. New, rapid, and less expensive techniques are necessary before diagnosis can be improved in these areas. The present work compared the performance of a rapid and costly culture media, thin layer agar (CD7H11), with the traditional Lowenstein-Jensen (LJ) culture method. For this comparison, 1,809 clinical specimens were processed for diagnosis of mycobacterial infections. Clinical samples were processed according to standard procedures and cultured concomitantly in LJ and CD7H11. The times required to obtain an isolate were compared for culture media. Sensitivity (S), specificity (Sp), predictive values (PPV, NPV) and agreement (kappa coefficient) were calculated for CD7H11, with LJ serving as the gold standard. CD7H11 showed S to be 73.5% (C.I.95%: 69.6-80.4), Sp to be 99.2% (C.I.95%: 98.8-99.6), PPV 90.4% (C.I.95%: 85.3-95.6) and NPV 97.6% (C.I.95%: 96.8-98.3). Agreement had a kappa coefficient of 0.52. The mean time for CD7H11 was 11 days (SD±4.9) compared with 26.5 (SD±8.6) days for LJ. Similar results were obtained in a comparison of respiratory and multibacillary clinical samples. In extrapulmonary samples and those with lowered bacillus count, CD7H11 demonstrated a lower sensitivity. The concomitant use of both culture media enhanced sensitivity of detection. CD7H11 proved a simple and rapid technique for culturing mycobacteria and can be combined with traditional methods for improving laboratory capability for diagnosis of tuberculosis.