ABSTRACT
BACKGROUND: Diagnosis of nontuberculous mycobacteria (NTM) infections remains a challenge. In this study, we describe the evaluation of an immunological NTM-interferon (IFN)-γ release assay (IGRA) that we developed using glycopeptidolipids (GPLs) as NTM-specific antigens. METHODS: We tested the NTM-IGRA in 99 samples from pediatric patients. Seventy-five were patients with lymphadenitis: 25 were NTM confirmed, 45 were of unknown etiology but compatible with mycobacterial infection and 5 had lymphadenitis caused by an etiologic agent other than NTM. The remaining 24 samples were from control individuals without lymphadenitis (latently infected with M. tuberculosis , uninfected controls and active tuberculosis patients). Peripheral blood mononuclear cells were stimulated overnight with GPLs. Detection of IFN-γ producing cells was evaluated by enzyme-linked immunospot assay. RESULTS: NTM culture-confirmed lymphadenitis patient samples had a significantly higher response to GPLs than the patients with lymphadenitis of unknown etiology but compatible with mycobacterial infection ( P < 0.001) and lymphadenitis not caused by NTM ( P < 0.01). We analyzed the response against GPLs in samples from unknown etiology lymphadenitis but compatible with mycobacterial infection cases according to the tuberculin skin test (TST) response, and although not statistically significant, those with a TST ≥5 mm had a higher response to GPLs when compared with the TST <5 mm group. CONCLUSIONS: Stimulation with GPLs yielded promising results in detecting NTM infection in pediatric patients with lymphadenitis. Our results indicate that the test could be useful to guide the diagnosis of pediatric lymphadenitis. This new NTM-IGRA could improve the clinical handling of NTM-infected patients and avoid unnecessary misdiagnosis and treatments.
Subject(s)
Lymphadenitis , Mycobacterium Infections, Nontuberculous , Mycobacterium tuberculosis , Tuberculosis , Humans , Child , Interferon-gamma Release Tests/methods , Leukocytes, Mononuclear , Tuberculosis/diagnosis , Tuberculin Test , Mycobacterium Infections, Nontuberculous/diagnosis , Lymphadenitis/diagnosisABSTRACT
OBJETIVO: El objetivo del estudio fue conocer la tendencia de las variables relacionadas con la tuberculosis (TB) en España a partir del registro del Programa Integrado de Investigación en Tuberculosis (PII-TB) de la Sociedad Española de Neumología y Cirugía Torácica (SEPAR) y evaluar el PII-TB mediante indicadores relacionados con sus objetivos científicos. MÉTODO: Estudio transversal multicéntrico de base poblacional de casos nuevos de TB registrados prospectivamente por el PII-TB entre 2006 y 2016. La tendencia temporal de variables cuantitativas se realizó mediante un modelo de regresión lineal y las cualitativas mediante la prueba de χ2 de tendencia lineal. RESULTADOS: Se analizaron 6.892 casos de TB con una mediana anual de 531. La tendencia general fue significativamente decreciente en mujeres, inmigrantes, privados de libertad y en tratados inicialmente con 3 fármacos. Se incrementaron significativamente la tendencia de grupos de 40 -50 años y > 50 años, primera atención por especialista de zona, hospitalización, retraso diagnóstico, localización diseminada y extrapulmonar única, cultivo (+), realización de antibiogramas, resistencia a fármacos, tratamiento directamente observado, prolongación del tratamiento y muerte por otra causa. Los objetivos científicos del PII-TB que incrementaron significativamente fueron las publicaciones alcanzando un máximo de 8 en 2016 y con un factor de impacto total de 49,664, y también mejoraron los proyectos iniciados anualmente, presentaciones en congresos y las tesis o tesinas. CONCLUSIONES: El PII-TB proporciona información relevante sobre la TB y sus factores asociados en España. Se ha formado un amplio equipo de investigadores y se han detectado aspectos científicos positivos y otros mejorables
OBJECTIVE: The objective of the study was to determine the trend of variables related to tuberculosis (TB) from the Integrated Tuberculosis Research Program (PII-TB) registry of the Spanish Society of Pulmonology and Thoracic Surgery (SEPAR), and to evaluate the PII-TB according to indicators related to its scientific objectives. METHOD: Cross-sectional, population-based, multicenter study of new TB cases prospectively registered in the PII-TB between 2006 and 2016. The time trend of quantitative variables was calculated using a lineal regression model, and qualitative variables using the χy test for lineal trend. RESULTS: A total of 6,892 cases with an annual median of 531 were analyzed. Overall, a significant downward trend was observed in women, immigrants, prisoners, and patients initially treated with 3 drugs. Significant upward trends were observed in patients aged 40-50 and > 50 years, first visit conducted by a specialist, hospitalization, diagnostic delay, disseminated disease and single extrapulmonary location, culture (+), sensitivity testing performed, drug resistance, directly observed treatment, prolonged treatment, and death from another cause. The scientific objectives of the PII-TB that showed a significant upward trend were publications, which reached a maximum of 8 in 2016 with a total impact factor of 49,664, numbers of projects initiated annually, presentations at conferences, and theses. CONCLUSIONS: PII-TB provides relevant information on TB and its associated factors in Spain. A large team of researchers has been created; some scientific aspects of the registry were positive, while others could have been improved
Subject(s)
Humans , Tuberculosis/prevention & control , Cross-Sectional Studies , Tuberculosis/epidemiology , Program Evaluation , Societies, Medical , Spain/epidemiology , PrevalenceABSTRACT
OBJECTIVE: The objective of the study was to determine the trend of variables related to tuberculosis (TB) from the Integrated Tuberculosis Research Program (PII-TB) registry of the Spanish Society of Pulmonology and Thoracic Surgery (SEPAR), and to evaluate the PII-TB according to indicators related to its scientific objectives. METHOD: Cross-sectional, population-based, multicenter study of new TB cases prospectively registered in the PII-TB between 2006 and 2016. The time trend of quantitative variables was calculated using a lineal regression model, and qualitative variables using the χy test for lineal trend. RESULTS: A total of 6,892 cases with an annual median of 531 were analyzed. Overall, a significant downward trend was observed in women, immigrants, prisoners, and patients initially treated with 3 drugs. Significant upward trends were observed in patients aged 40-50 and > 50 years, first visit conducted by a specialist, hospitalization, diagnostic delay, disseminated disease and single extrapulmonary location, culture(+), sensitivity testing performed, drug resistance, directly observed treatment, prolonged treatment, and death from another cause. The scientific objectives of the PII-TB that showed a significant upward trend were publications, which reached a maximum of 8 in 2016 with a total impact factor of 49,664, numbers of projects initiated annually, presentations at conferences, and theses. CONCLUSIONS: PII-TB provides relevant information on TB and its associated factors in Spain. A large team of researchers has been created; some scientific aspects of the registry were positive, while others could have been improved.
Subject(s)
Pulmonary Medicine , Thoracic Surgery , Tuberculosis , Cross-Sectional Studies , Delayed Diagnosis , Female , Humans , Spain/epidemiologyABSTRACT
RATIONALE: The identification of patients with latent tuberculosis infection, who are at higher risk to develop active disease, is an important component of disease control. OBJECTIVES: We aim to compare the usefulness of the QuantiFERON-TB Gold in-tube assay and the tuberculin skin test to predict the development of active tuberculosis during follow-up, using positive and negative predictive values, positive likelihood ratios, and stratified level of risk. METHODS: The study included contacts of tuberculosis cases diagnosed between 2007 and 2009. All contacts included were from the first circle of exposure. Tuberculin skin test and QuantiFERON test were performed and a chest radiograph was obtained during the contact's study. MEASUREMENTS AND MAIN RESULTS: A total of 1,335 contacts were followed up for 4 years: a smear-positive index case was identified for 937 contacts, of whom 15 developed active tuberculosis and had initially presented with positive tuberculin skin test/QuantiFERON results, a normal chest radiograph, and no symptoms. The positive predictive value was 4% for QuantiFERON and 2% for the tuberculin skin test (when ≥5 mm). The probability of developing active disease was 2.36 times higher with a positive QuantiFERON, and 1.3 times higher with a positive tuberculin skin test. The positive predictive value was 17%, and the positive likelihood ratio was 7.53 for untreated contacts with a positive QuantiFERON. Stratifying according to initial QuantiFERON results showed a 6.36 times higher risk of developing active tuberculosis for patients with a QuantiFERON result greater than or equal to 10 IU/ml. Among bacillus Calmette-Guérin-vaccinated patients, a tuberculin skin test induration greater than or equal to 15 mm correlated better with a positive QuantiFERON. CONCLUSIONS: QuantiFERON results were more accurate than tuberculin skin test results in predicting tuberculosis. Although all contacts with QuantiFERON-positive results are at risk of developing tuberculosis, those with a tuberculin skin test induration greater than or equal to 15 mm and QuantiFERON greater than or equal to 10 IU/ml are at highest risk. This has important implications in the clinical management of tuberculosis contacts.
Subject(s)
Interferon-gamma Release Tests/methods , Latent Tuberculosis/diagnosis , Tuberculin Test/methods , Adolescent , Adult , Child , Child, Preschool , Female , Follow-Up Studies , Humans , Incidence , Infant , Infant, Newborn , Latent Tuberculosis/epidemiology , Male , Mycobacterium tuberculosis/immunology , Mycobacterium tuberculosis/isolation & purification , Retrospective Studies , Spain/epidemiology , Young AdultABSTRACT
The aim of our work here was to evaluate the immunogenicity of 60 mycobacterial antigens, some of which have not been previously assessed, notably a novel series of in vivo-expressed Mycobacterium tuberculosis (IVE-TB) antigens. We enrolled 505 subjects and separated them in individuals with and without latent tuberculosis infection (LTBI) vs. patients with active tuberculosis (TB). Following an overnight and 7 days stimulation of whole blood with purified recombinant M. tuberculosis antigens, interferon-γ (IFN-γ) levels were determined by ELISA. Several antigens could statistically significantly differentiate the groups of individuals. We obtained promising antigens from all studied antigen groups [dormancy survival regulon (DosR regulon) encoded antigens; resuscitation-promoting factors (Rpf) antigens; IVE-TB antigens; reactivation associated antigens]. Rv1733, which is a probable conserved transmembrane protein encoded in DosR regulon, turned out to be very immunogenic and able to discriminate between the three defined TB status, thus considered a candidate biomarker. Rv2389 and Rv2435n, belonging to Rpf family and IVE-TB group of antigens, respectively, also stood out as LTBI biomarkers. Although more studies are needed to support our findings, the combined use of these antigens would be an interesting approach to TB immunodiagnosis candidates.
