Discordancia entre pruebas de susceptibilidad genotípicas y fenotípicas para tuberculosis en Cali, Colombia: un reto en la práctica clínica / Discordance between genotypic and phenotypic susceptibility tests for tuberculosis in Cali, Colombia: a challenge in the clinical practice

INTRODUCCIÓN: La detección de patrones de resistencia de Mycobacterium tuberculosis se basa en pruebas de susceptibilidad fenotípicas y genotípicas. Los resultados discordantes entre ellas son un desafío clínico para el manejo de pacientes con tuberculosis resistente a fármacos. OBJETIVO: Evaluar la concordancia entre pruebas fenotípicas y moleculares en pacientes con tuberculosis resistente a fármacos atendidos en una institución de Cali, Colombia. MATERIALES Y MÉTODOS: Se realizó un estudio transversal en el que se obtuvo el perfil de sensibilidad fenotípico de cultivos de micobacterias y la susceptibilidad genotípica con las pruebas moleculares Xpert-MTB/ RIF® o Genotype-MDRTBplus ®. Se evaluó el porcentaje de resistencia y porcentaje de acuerdo entre los resultados de las pruebas fenotípicas y genotípicas. Se estimó un coeficiente de kappa de Cohen (κ) para cada tipo de resistencia según la prueba utilizada. RESULTADOS: Se incluyeron 30 casos con resultados de pruebas genotípicas y fenotípicas. Las pruebas fenotípicas detectaron resistencia a fármacos de primera línea en 29/30 casos, mientras que las moleculares detectaron la resistencia en todos los casos evaluados. El porcentaje de resistencia a rifampicina detectado entre la prueba fenotípica y Genotype-MDRTBplus ® &e 61,5% (acuerdo global 41,1%, κ = 0,40, p = 0,96), mientras que el porcentaje de resistencia detectado con Xpert-MTB/RIF® fue 100% (acuerdo global 81,82%, κ: 0,00, p < 0,001) para este mismo medicamento. El porcentaje de resistencia a isoniacida detectado entre la prueba fenotípica y Genotype-MDRTBplus ® fue 94,4% (acuerdo global 89,47%, κ: -0,055 p = 0,59). CONCLUSIONES: La discordancia entre los resultados de las pruebas genotípicas y fenotípicas es posible, por lo que es importante usar e interpretar ambos tipos de pruebas de manera complementaria en el diagnóstico de la resistencia a fármacos de primera línea en la infección por M. tuberculosis.

BACKGROUND: The detection of Mycobacterium tuberculosis resistance patterns is based on phenotypic and genotypic susceptibility tests. The discordant results between them are a clinical challenge for the management of patients with drug-resistant tuberculosis. Aim: To evaluate the concordance between phenotypic and molecular tests in patients with drug-resistant tuberculosis treated in an institution in Cali, Colombia. METHODS: A cross-sectional study was conducted. A phenotypic sensitivity profile was obtained from mycobacterial cultures. The genotypic susceptibility was obtained with Xpert-MTB/ RIF® or Genotype-MDRTBplus ®. The percentage of resistance and percentage of agreement between the results of the phenotypic and genotypic tests were evaluated. A Cohen's kappa coefficient (κ) was estimated for each type of resistance according to the test used. RESULTS: A total of 30 cases with both genotypic and phenotypic testing were included. The phenotypic tests detected resistance to first-line drugs in 29/30 cases, while the molecular tests detected resistance in all the cases evaluated. The percentage of resistance detected between Genotype-MDRTBplus® and the phenotypic test for rifampicin was 61.5% (overall agreement 41.1%, κ = 0.40, p = 0.96), while the percentage of resistance detected with XpertMTB/RIF® was 100% (overall agreement 81.82%, κ: 0.00, p < 0.001) for this same drug. Resistance to isoniazid detected by both types of tests was 94.4% (overall agreement 89.47%, κ: -0.055 p = 0.59). CONCLUSIONS: Discordance between the results of genotypic and phenotypic tests is possible, so it is important to use and interpret both types of tests in a complementary way in the diagnosis of resistance to first-line drugs in M. tuberculosis infection.

Development, characterization and anti - Mycobacterium tuberculosis activity of solid lipid nanoparticles for oral Piper corcovadensis roots extract delivery / Desarrollo, caracterización y actividad anti - Mycobacterium tuberculosis de nanopartículas lipídicas sólidas para la administración oral de extracto de raíces de Piper corcovadensis

The present study thus aimed at the development and physicochemical characterization of solid lipid nanoparticles loaded with crude extract of Piper corcovadensis roots (SLN - CEPc) and chitosan - coated solid lipid nanoparticles loaded with crude extract of P. corcovadensis roots (C - SLN - CEPc), as well as the determination of its antimycobacterial activity against Mycobacterium tuberculosis H37Rv, its cytotoxicity against the Vero cell line and evaluation in the hemolysis assay. Both formulat ions containing the encapsulated extract showed high encapsulation efficiency, formed by a monodispersed system with small and spherical particles, and there was no aggregation of particles. In the biological assays, SLN - CEPc and C - SLN - CEPc showed promisin g anti - M. tuberculosis activity with a minimum inhibitory concentration (MIC) of 12.5 µg/mL, whereas the cytotoxic concentrations obtained at 50% (CC 50 ) in Vero cells were 60.0 and 70.0 µg/mL, respectively. Therefore, nanoencapsulation showed satisfactory results, justifying its usage in the development of new products.

El presente estudio apuntó al desarrollo y caracterización fisicoquímica de na nopartículas lípidas en estado sólido, cargadas con extracto crudo de raíz de Piper c orcovadensis (SLN - CEPc) y nanopartículas lípidas en estado sólido cubiertas con quitosano cargadas co n extracto crudo de raíz de P. corcovadensis (C - SLN - CEPc), así como la determinación de su actividad antimico bacterial contra Mycobacterium tuberculosis H37Rv, su citotoxicidad contra la línea celular Vero y su evaluación en ensayo de hemólisis. Ambas formulaciones que contenían el extracto encapsulado mostraron alta eficien cia de encapsulación, formado por un sistema monodispersado con pequeñas partículas esféricas, y no hubo agregación de partículas. En los ensayos biológicos, SLN - CEPc y C - SLN - CEPc mostraron un a prometedora actividad anti - M. tuberculosis con una mínima conc entración inhibitoria (MIC) de 12,5 µg/mL, mientras que las concentraciones citotóxicas obtenidas al 50% (CC 50 ) en células Vero estuvo en 60,0 y 70,0 µg/mL, respectivamente. Por lo tanto, la nanoencapsulación mostró resultados satisfactorios, justificando su uso en el desarrollo de nuevos productos.

Diversidad genética de Mycobacterium tuberculosis circulando en la jurisdicción V de Jalapa, Veracruz, México / Genetic diversity of Mycobacterium tuberculosis circulating in the jurisdiction V from Jalapa, Veracruz, Mexico

ANTECEDENTES: El estado de Veracruz se ubica en el sureste de México y presenta una alta prevalencia de tuberculosis (TBC) y drogo resistencia. Sin embargo, la composición de los genotipos circulantes es poco conocida. OBJETIVO: Caracterizar la diversidad genética de la TBC en la jurisdicción sanitaria V del estado de Veracruz. MÉTODOS: Estudio transversal realizado en aislados clínicos de pacientes con TBC residentes de la jurisdicción V. Se determinó la sensibilidad a medicamentos de primera línea. La genotipificación se realizó mediante espoligotipificación y MIRU-VNTR 15 loci. RESULTADOS: Entre los 74 aislados analizados se observó resistencia a un fármaco en 44 (59%) aislados. Linaje L4 (EuroAmericano) se presentó en 73 aislados. Se identificaron cinco sublinajes; H (40%), T (22%), LAM (16%), X (13%) y U (7%). El 32% de los aislados se agrupó mediante su espoligotipo y 40% en 10 complejos clonales. CONCLUSIONES: Es la primera descripción sobre la estructura genética de TBC en la región central de Veracruz. La diversidad de genotipos podría contribuir a su dispersión en la región. Esta información será útil para el desarrollo de intervenciones y reducir el impacto de TBC en la población.

BACKGROUND: The state of Veracruz is placed in southeastern Mexico and has a high prevalence of tuberculosis (TB) and drug resistance. Nevertheless, the composition of circulating genotypes in the central region of the state is partially known. AIM: To characterize the genetic diversity of TB in the sanitary jurisdiction V of the state of Veracruz. METHODS: A cross-sectional study was conducted among clinical isolates from patients with TB living in the jurisdiction V, in Jalapa Ver., Mexico. Sensitivity to first-line drugs was determined, and genotyping was performed by spoligotyping and MIRU-VNTR 15 loci. RESULTS: Among the 74 isolates analyzed, resistance to one drug was observed in 44 isolates. L4 (EuroAmerican) was the major lineage identified. Five sublineages were the most abundant; H (40%), T (22%), LAM (16%), X (13%) and U (7%). Only 32% of the isolates were clustered by spoligotype and 40% were placed in ten clonal complexes. CONCLUSIONS: This is the first description of the genetic structure of TB in the central region of Veracruz. The diversity of genotypes could contribute to its dispersion. This information will be useful for the development of interventions to reduce the impact of TB in the population.

Empiema de necesidad / Empyema of Necessity

Introducción: El empiema de necesidad o empiema necessitatis (del latín) es un hallazgo raro en la actualidad y la tuberculosis es la causa más común, sobre todo en pacientes inmunodeprimidos. Objetivo: Presentar un caso con un empiema de necesidad como complicación de la tuberculosis extrapulmonar Caso clínico: Paciente de sexo femenino de 47 años de edad, sin antecedentes de enfermedad conocidos. Ingresa por una neumonía de la base derecha y como complicación un empiema de necesidad de naturaleza tuberculosa. Es tratada de forma médica y quirúrgica, tuvo una evolución favorable. Conclusiones: El conocimiento de la epidemiología de la zona donde se diagnosticó la enferma y la medicina personalizada contribuyeron a un diagnóstico rápido y a un tratamiento médico y quirúrgico acorde a los protocolos establecidos para la tuberculosis extrapleural(AU)

Introduction: Empyema of necessity (or empyema necessitatis) is, at present, a rare finding, of which tuberculosis is the most common cause, especially in immunosuppressed patients. Objective: To present a case of empyema of necessity as a complication of extrapulmonary tuberculosis. Clinical case: 47-year-old female patient, without known history of disease, who was admitted due to pneumonia of the right base and, as a complication, an empyema of necessity of a tubercular nature. She was treated medically and surgically, and had a favorable evolution. Conclusions: Knowledge of the epidemiology of the area where the patient was diagnosed, together with personalized medical care, contributed to a rapid diagnosis, as well as to the medical and surgical treatment provided according to the protocols established for extrapleural tuberculosis(AU)

Perfil de resistencia del Mycobacterium tuberculosis a fármacos antituberculosos de primera línea y sus combinaciones / Resistance profile of Mycobacterium tuberculosis to first-line antituberculosis drugs and their combinations

Introducción: En Colombia el control de la tuberculosis se ha visto amenazado por la resistencia a los fármacos antituberculosos y especialmente la tuberculosis multidrogorresistente. Objetivo: Determinar la resistencia global y perfiles de resistencia del Mycobacterium tuberculosis a fármacos antituberculosos de primera línea y combinaciones. Métodos: Estudio descriptivo, transversal, en el que se evaluaron 2 701 pacientes con tuberculosis en el Departamento del Atlántico (Colombia), durante los años 2011 a 2016. Se valoraron aspectos sociodemográficos, clínicos y condiciones de riesgo. Se realizó análisis de frecuencias relativas y absolutas, diferencia de proporciones ((2) y razón de prevalencias. Resultados: El 66,5 por ciento de los pacientes eran hombres, el 53 por ciento tenían entre 15 y 44 años de edad. El 47,34 por ciento con pérdida en el seguimiento y el 11,62 por ciento monorresistentes a isoniacida. La resistencia en casos nuevos fue 7,30 por ciento (IC95 por ciento: 6,3-8,5), para este grupo la multidrogorresistencia fue de 1,1 por ciento; mientras que en los previamente tratados la resistencia fue de 18,27 por ciento (IC95 por ciento: 15,6- 22,4) y la multidrogorresistencia de 5,7 por ciento. Los factores asociados a resistencia fueron presencia de VIH/TB (RP= 2,6; p= 0,000), otros factores inmunosupresores (RP= 3,5; p= 0,009), contacto de paciente con tuberculosis multidrogorresistente (RP= 16; p= 0,000) y caso previamente tratado (RP= 2,24; p= 0,00). Conclusiones: Se evidencia un descenso en la resistencia global a rifampicina e isoniacida, así como en la prevalencia multidrogorresistente tanto en casos nuevos como en previamente tratados en la población estudiada; lo que genera una línea base para la toma de decisiones que permita continuar mejorando la vigilancia y control de la resistencia del M. tuberculosis a fármacos de primera línea, debido a los nuevos retos que este microorganismo representa para la salud pública(AU)

Introduction: Tuberculosis control in Colombia has been hampered by resistance to antituberculosis drugs and particularly by multi-drug resistant tuberculosis. Objective: Determine the overall resistance and resistance profiles of Mycobacterium tuberculosis to first-line antituberculosis drugs and their combinations. Methods: A descriptive cross-sectional study was conducted of 2 701 tuberculosis patients from Atlántico Department in Colombia in the period 2011-2016. The evaluation included sociodemographic aspects, clinical characteristics and risk conditions. Data analysis was based on relative and absolute frequencies, proportion difference (x2) and prevalence ratio. Results: Of the total sample, 66.5 percent were men and 53 percent were aged 15-44 years. 47.34 percent were lost to follow-up and 11.62 percent were monoresistant to isoniazid. In new cases resistance was 7.30 percent (CI 95 percent: 6.3-8.5) and multi-drug resistance was 1.1 percent, whereas in previously treated cases resistance was 18.27 percent (CI 95 percent: 15.6-22.4) and multi-drug resistance was 5.7 percent. The factors associated to resistance were the presence of HIV/TB (AR= 2.6; p= 0.000), other immunosuppressive factors (AR= 3.5; p= 0.009), contact with multi-drug resistant tuberculosis patient (AR= 16; p= 0.000) and previously treated case (AR= 2.24; p= 0.00). Conclusions: A reduction is observed in overall resistance to rifampicin and isoniazid, as well as in the prevalence of multi-drug resistance, both in new cases and in previously treated cases, which creates a baseline for the taking of decisions aimed at the continuing improvement of the surveillance and control of M. tuberculosis resistance to first-line drugs, due to the new challenges posed by this microorganism to public health(AU)

Resistencia cruzada entre isoniacida y etionamida y su alta correlación con la mutación C-15T en aislamientos de Mycobacterium tuberculosis de Perú / Cross-resistance between isoniazid and ethionamide and its strong association with mutation C-15T in Mycobacterium tuberculosis isolates from Peru

Resumen Diversos estudios han evidenciado una resistencia cruzada entre isoniacida y etionamida, 2 de los fármacos utilizados en el tratamiento de la tuberculosis multirresistente.El objetivo del presente estudio fue determinar la resistencia cruzada entre ambos fármacos en aislados de Mycobacterium tuberculosis obtenidos en un hospital de Lima (Perú), conalta proporción de pacientes con tuberculosis. Se calculó la frecuencia de mutaciones asociadas con la resistencia a la isoniacida (INH) evaluando el gen katG y la región promotorainhA mediante la prueba molecular Genotype MTBDRplus v2.0. El método gold standard conocido como agar proporciones en placa (APP) permitió la identificación de resistencia a INH yetionamida. De 107 aislamientos resistentes a INH, 54 fueron multirresistentes (identificadosmediante la prueba Genotype MTBDRplus) y 49 (es decir, el 45,8% del total) también fueronresistentes a etionamida por el método APP. En los aislamientos resistentes a INH, se encontraron mutaciones en el gen katG en el 50,5% (54/107); en la región promotora inhA en el23,3% (25/107), y un 14,0% (15/107) presentaron mutaciones en ambos. Un 12,1% (13/107)fueron resistentes a INH por ausencia de banda wild type y banda de mutación. La mutaciónC-15T en la región promotora inhA presentó una fuerte asociación con la resistencia a etionamida y alcanzó el 73,4% (36/49) de los aislamientos resistentes a dicho fármaco. Los resultadosdel presente estudio sugieren que la identificación de mutaciones relacionadas con resistenciaa INH, sobre todo en la región promotora inhA, podría ser de gran utilidad para identificarla resistencia cruzada a etionamida y mejorar el tratamiento de las personas afectadas portuberculosis.© 2019 Asociacion Argentina de Microbiolog´ía. Publicado por Elsevier Espana, S.L.U. Este es unart´ículo Open Access bajo la licencia CC BY-NC-ND (https://creativecommons.org/licenses/by-nc-nd/4.0/).

Abstract Several studies have shown cross-resistance between isoniazid and ethionamide, 2of the drugs used in the treatment of multidrug-resistant tuberculosis. The objective of this study was to determine the cross-resistance between both drugs in Mycobacterium tuberculosis isolates from a hospital with high incidence of tuberculosis in Lima, Peru. The frequency of mutations to isoniazid in the katG gene and the inhA promoter region was identified by the Genotype MTBDRplus v2.0 molecular test. The gold standard Agar Proportion method (APM) allowed todetect resistance to isoniazid and ethionamide. Of 107 isoniazid-resistant isolates (54 multidrug-resistant isolates identified by the Genotype MTBDRplus test, 45.8% (49/107) were also resistant to ethionamide by the APM. Mutations were found in the katG gene in 50.5% (54/107), in the promoter region inhA in 23.3% (25/107) and 14.0% (15/107) that share both mutations in the resistant isolates to INH. The absence of the wild type and mutation bands indicated that 12.1% (13/107) of the isolates were resistant to INH. The mutation C-15T in the inhA promoter region showed a strong association with resistance to ethionamide in 73.4% (36/49) of the isolates analyzed. The results of the present study suggest that the identification of mutations related to resistance to isoniazid, especially in the inhA promoter region, could be very useful to identify cross-resistance to ethionamide and improve the treatment of individuals suffering from this disease.

Evaluation of drug susceptibility profile of Mycobacterium tuberculosis Lineage 1 from Brazil based on whole genome sequencing and phenotypic methods

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.

Brazilian Green Propolis: Chemical Composition of Essential Oil and Their In Vitro Antioxidant, Antibacterial and Antiproliferative Activities

Abstract Propolis is a resinous substance collected and processed by Apis mellifera from parts of plants, buds and exudates. In Minas Gerais (MG) state, Brazil, green propolis is produced from the collection of resinous substance found in shoot apices of Baccharis dracunculifolia. This paper aims to investigate the chemical composition and in vitro antioxidant, anti-Helicobacter pylori, antimycobacterial and antiproliferative activities of essential oil (EO) from Brazilian green propolis (BGP-EO). The oil showed high antibacterial activity against H. pylori (MIC = 6.25 µg/mL), Mycobacterium avium (MIC = 62.5 µg/mL) and M. tuberculosis (MIC = 64 µg/mL). Its antioxidant activity was evaluated in vitro by both DPPH (IC50 = 23.48 µg/mL) and ABTS (IC50 = 32.18 µg/mL) methods. The antiproliferative activity in normal (GM07492A, lung fibroblasts) and tumor cell lines (MCF-7, HeLa and M059J) was analyzed by the XTT assay. BGP-EO showed inhibition of normal cell growth at 68.93 ± 2.56 µg/mL. Antiproliferative activity was observed against human tumor cell lines, whose IC50 values were 56.17, 66.43 and -65.83 µg/mL for MCF-7, HeLa and M059J cells, respectively. Its major constituents, which were determined by GC-FID and GC-MS, were carvacrol (20.7 %), acetophenone (13.5 %), spathulenol (11.0 %), (E)-nerolidol (9.7 %) and β-caryophyllene (6.2 %). These results showed the effectiveness of BGP-EO as a natural product which has promising biological activities.

Detection of Drug Resistant Mycobacterium Tuberculosis Strains Using Kit SIRE Nitratase®: a Multicenter Study

Abstract (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.

Factors associated with tuberculosis and multidrug-resistant tuberculosis in patients treated at a tertiary referral hospital in the state of Minas Gerais, Brazil / Fatores associados à tuberculose e à tuberculose multirresistente em pacientes atendidos em um hospital de referência terciária em Minas Gerais, Brasil

ABSTRACT Objective: To evaluate the risk factors for the development of tuberculosis and multidrug-resistant tuberculosis (MDR-TB) in patients treated at a tertiary referral hospital. Methods: This was a cross-sectional study based on data obtained from patients treated at the Júlia Kubitschek Hospital, located in the city of Belo Horizonte, Brazil, between October of 2012 and October of 2014. We evaluated sociodemographic, behavioral, clinical, and radiological variables. The outcome considered to identify associations between tuberculosis and the explanatory variables was the treatment prescribed. To evaluate the associations between MDR-TB and the same explanatory variables, the change in MDR-TB treatment was considered. Results: The factors associated with tuberculosis were alcoholism, comorbidities, pulmonary cavitations, and a radiological pattern suggestive of tuberculosis. Cavitation and previous treatment for tuberculosis were associated with MDR-TB. Conclusions: Despite the significant progress made in the fight against tuberculosis, there is a need for coordinated actions that include social protection measures and patient support.

RESUMO Objetivo: Avaliar os fatores de risco de pacientes atendidos em um hospital de referência terciária para o desenvolvimento de tuberculose e tuberculose multirresistente (TBMR). Métodos: Estudo transversal baseado em dados obtidos de pacientes atendidos no Hospital Júlia Kubitschek, na cidade de Belo Horizonte (MG), entre outubro de 2012 e outubro de 2014. As variáveis utilizadas foram agrupadas em características sociodemográficas, comportamentais, clínicas e radiológicas. O desfecho considerado para verificar associações entre tuberculose e variáveis explicativas foi o tratamento prescrito para tuberculose. Para avaliar a associação entre a tuberculose resistente e as mesmas variáveis explicativas considerou-se a mudança de tratamento para TBMR. Resultados: Alcoolismo, padrão radiológico sugestivo de tuberculose, presença de comorbidades e presença de cavitações pulmonares foram fatores associados à tuberculose. A TBMR foi associada a tratamento prévio para tuberculose e presença de cavitações. Conclusões: Apesar dos importantes progressos na luta contra a tuberculose, é necessário um conjunto de ações articuladas que incluam medidas de proteção social e suporte aos pacientes.

Rapid detection of Mycobacterium tuberculosis DNA and genetic markers for Isoniazid resistance in Ziehl-Neelsen stained slides

BACKGROUND Early diagnosis of tuberculosis (TB) and identification of strains of Mycobacterium tuberculosis resistant to anti-TB drugs are considered the main factors for disease control. OBJECTIVES To standardise a real-time polymerase chain reaction (qPCR) assay technique and apply it to identify mutations involved in M. tuberculosis resistance to Isoniazid (INH) directly in Ziehl-Neelsen (ZN) stained slides. METHODS Were analysed 55 independent DNA samples extracted from clinical isolates of M. tuberculosis by sequencing. For application in TB diagnosis resistance, 59 ZN-stained slides were used. The sensitivity, specificity and Kappa index, with a 95% confidence interval (CI95%), were determined. FINDINGS The agreement between the tests was, for the katG target, the Kappa index of 0.89 (CI95%: 0.7-1.0). The sensitivity and specificity were 97.6% (CI95%: 87.7-99.9) and 91.7% (CI95%: 61.5-99.5), respectively. For inhA, the Kappa index was 0.92 (CI95%: 0.8-1.0), the sensitivity and specificity were 94.4% (CI95%: 72.7-99.8) and 97.3% (CI95%: 85.8-99.9), respectively. The use of ZN-stained slides for drug-resistant TB detection showed significant results when compared to other standard tests for drug resistance. MAIN CONCLUSIONS qPCR genotyping proved to be an efficient method to detect genes that confer M. tuberculosis resistance to INH. Thus, qPCR genotyping may be an alternative instead of sequencing.

Transmission and prevalence of drug-resistant tuberculosis in a Brazilian setting under a directly observed therapy short-course strategy

Abstract INTRODUCTION: We aimed to estimate the prevalence and transmission of drug-resistant tuberculosis in a high-burden Brazilian setting under directly observed therapy short-course strategy. METHODS: Isolates of culture-confirmed pulmonary tuberculosis patients from Guarulhos, Brazil, diagnosed in October 2007-2011 were subjected to drug susceptibility and IS6110-restriction fragment length polymorphism testing. RESULTS: The overall resistance prevalence was 11.5% and the multi-drug resistance rate was 4.2%. Twenty-six (43.3%) of 60 drug-resistant isolates were clustered. Epidemiological relationships were identified in 11 (42.3%) patients; 30.8% of the cases were transmitted in households. CONCLUSIONS: Drug-resistant tuberculosis was relatively low and transmitted in households and the community.

Frequency of first and second-line drug resistance-associated mutations among resistant Mycobacterium tuberculosis clinical isolates from São Paulo, Brazil

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.

Mutaciones que confieren resistencia a fármacos antituberculosis de primera línea en Perú: una revisión sistemática de la literatura / Mutations conferring resistance to first-line anti-tuberculosis drugs in Peru: a systematic review of the literature

RESUMEN Objetivos. Sistematizar la información disponible referente a las mutaciones que confieren resistencia a los fármacos antituberculosis de primera línea. Materiales y métodos. Se realizó una revisión sistemática de la literatura científica para identificar artículos que reportaron mutaciones que confieren resistencia a fármacos antituberculosis de primera línea. Esta búsqueda hizo énfasis en la resistencia a los fármacos de isoniazida y rifampicina en cepas de M. tuberculosis de pacientes peruanos. La búsqueda fue realizada en PubMed y LILACS (Literatura Latinoamericana y del Caribe en Ciencias de la Salud). Resultados. Se incluyeron 14 artículos de los cuales tres reportaron mutaciones asociadas con resistencia a isoniazida, seis a rifampicina, ocho a pirazinamida y uno a etambutol. Todas las mutaciones a isoniazida o rifampicina fueron identificadas directa o indirectamente mediante la prueba de diagnóstico molecular GenoType MTBDRplus® v2.0. La mayor variabilidad de mutaciones fue determinada en la resistencia a pirazinamida. Conclusiones. Existe una gran variabilidad de mutaciones asociadas con resistencia a fármacos antituberculosis que han sido reportadas en Perú, y se sistematizan en el presente reporte. Estas mutaciones deben de ser tomadas en cuenta para el desarrollo de dispositivos diagnósticos o selección de pruebas diagnósticas a ser aplicadas en nuestro país.

ABSTRACT Objective. To systematize available information regarding mutations that confer resistance to first-line anti-tuberculosis drugs. Materials and Methods. A systematic review of the scientific literature was conducted to identify articles that reported mutations conferring resistance to first-line anti-tuberculosis drugs. This search emphasized resistance to isoniazid and rifampicin drugs in M. tuberculosis strains of Peruvian patients. The search was performed on PubMed and LILACS (Latin American and Caribbean Health Sciences Literature). Results. Fourteen (14) articles were included, of which three reported mutations associated with resistance to isoniazid, six to rifampicin, eight to pyrazinamide and one to ethambutol. All mutations to isoniazid or rifampicin were identified directly or indirectly by the molecular diagnostic test GenoType MTBDRplus® v2.0. The greatest variability of mutations was determined in resistance to pyrazinamide. Conclusions. There is a great variability of mutations associated with resistance to anti-tuberculosis drugs that have been reported in Peru, and they are systematized in this report. These mutations must be taken into account for the development of diagnostic devices or selection of diagnostic tests to be applied in our country.

Aspectos clínicos e tratamento de pacientes com tuberculose ocular presumida em centro de referência de São Paulo, Brasil. Estudo retrospectivo / Clinical description and treatment of patients with presumed ocular tuberculosis in São Paulo, Brazil. Retrospective study

Resumo Objetivo: Descrever aspectos clínicos e esquema terapêutico dos pacientes com tuberculose ocular presumida tratados em um centro de referência em tuberculose de São Paulo. Métodos: Estudo retrospectivo descritivo. O teste exato de Fisher foi realizado quando apropriado. Resultados: A queixa mais comum foi baixa acuidade visual (83,1%), seguida por dor ocular generalizada (25,3%) e visão turva (22,8%). A uveíte posterior foi a apresentação mais comum (35,7%). O tratamento consistiu no esquema atualmente recomendado de rifampicina, isoniazida, pirazinamida e etambutol (RHZE). A prednisona oral foi incluída no tratamento de 37 pacientes, para tratamento da inflamação aguda, embora não tenha diminuído a prevalência de complicações crônicas, em comparação com a recuperação completa (p = 0,1). O diagnóstico precoce (<70 dias) foi associado a maiores taxas de recuperação total (p = 0,005). Não houve significância estatística quando se comparou a terapia de 6 a 9 meses (p = 0,7). Conclusão: A uveíte tuberculosa pode ser tratada por uma terapia com duração de seis meses. Um breve curso de esteroides melhora os sintomas agudos, embora não reduza as complicações a longo prazo.

Abstract Purpose: To analyze and describe the therapy used in presumed ocular tuberculosis in a referral center in São Paulo, Brazil. Methods: Retrospective, descriptive study. Fisher's exact test was performed when appropriate. Results: The most common complaint was low visual acuity (83.1%), followed by generalized ocular pain (25.3%) and blurred vision (22.8%). Posterior uveitis was the most common presentation (35.7%). Treatment consisted of the currently recommended association of rifampin, isoniazid, pyrazinamide, ethambutol (RHZE) regimen. Oral prednisone was included in the treatment of 37 patients for acute inflammation, although it did not significantly decrease the prevalence of chronic complications compared to full recovery (p = 0,1). Early diagnosis (< 70 days) was associated with higher rates of full recovery (p = 0.005). No statistical significance was observed when comparing 6 to 9-month therapy (p = 0.7). Conclusion: Tuberculous uveitis can be treated with a 6-month duration RHZE therapy. A brief course of steroids may improve acute symptoms, although it did not reduce long-term disabilities.

Synthesis, characterization, and in vitro evaluation of gamma radiationinduced PEGylated isoniazid

Background: The search for innovative anti-tubercular agents has received increasing attention in tuberculosis chemotherapy because Mycobacterium tuberculosis infection has steadily increased over the years. This underlines the necessity for new methods of preparation for polymer-drug adducts to treat this important infectious disease. The use of poly(ethylene glycol)(PEG) is an alternative producing anti-tubercular derivatives. However, it is not yet known whether PEGylated isonicotinylhydrazide conjugates obtained by direct links with PEG are useful for therapeutic applications. Results: Here, we synthesized a PEGylated isoniazid (PEG-g-INH or PEG­INH) by gamma radiation-induced polymerization, for the first time. The new prodrugs were characterized using Raman and UV/Vis spectrometry. The mechanism of PEGylated INH synthesis was proposed. The in vitro evaluation of a PEGylated isonicotinylhydrazide macromolecular prodrug was also carried out. The results indicated that PEG­INH inhibited the bacterial growth above 95% as compared with INH, which showed a lower value (80%) at a concentration of 0.25 µM. Similar trends are observed for 0.1, 1, and 5 µM. Conclusions: In summary, the research suggests that it is possible to covalently attach the PEG onto INH by the proposed method and to obtain a slow-acting isoniazid derivative with little toxicity in vitro and higher antimycobacterial potency than the neat drug.

Abandono del tratamiento en tuberculosis multirresistente: factores asociados en una región con alta carga de la enfermedad en Perú / Abandonment of therapy in multidrug-resistant tuberculosis: Associated factors in a region with a high burden of the disease in Perú

Resumen Introducción. En la tuberculosis multirresistente, el abandono del tratamiento constituye un grave problema de salud pública que afecta la calidad de vida de los pacientes, sus familias y la comunidad. El enfrentarlo supone una carga para los sistemas sanitarios debido a que provoca fuentes de transmisión libre en la comunidad e incrementa la prevalencia y la mortalidad. De ahí, la necesidad de investigar los factores asociados con esta situación. Objetivo. Determinar los factores de riesgo asociados con el abandono del tratamiento en pacientes con tuberculosis multirresistente en la región de Callao (Perú). Materiales y métodos. Se hizo un estudio analítico de casos y controles (80 casos y 180 controles) en tratamiento entre el 1° enero del 2010 y el 31 diciembre del 2012. Los factores se determinaron mediante regresión logística, y se calcularon los odds ratios (OR) y los intervalos de confianza (IC) del 95 %. Resultados. En el análisis multivariado se determinaron los siguientes factores de riesgo: no tener conocimiento de la enfermedad (OR=23,10; IC95%: 3,6-36,79; p=0,002); no creer en la curación (OR=117,34; IC95%: 13,57-124,6; p=0,000); no tener apoyo social (OR=19,16; IC95%: 1,32-27,77; p=0,030); no considerar adecuado el horario de atención (OR=78,13; IC95%: 4,84-125,97; p=0,002), y no recibir los resultados de laboratorio (OR=46,13; IC95%: 2,85-74,77; p=0,007). Conclusión. Los servicios de salud deben esforzarse en la determinación precoz de las condiciones que podrían convertirse en factores de riesgo, lo cual ayudaría a implementar preventivamente intervenciones efectivas, rápidas y de alto impacto.

Abstract Introduction: In the context of multidrug-resistant tuberculosis, abandonment of therapy represents a serious public health problem that affects the quality of life of patients, families, and communities. Managing this phenomenon places a burden on health systems since it causes free sources of transmission in the community, thereby increasing prevalence and mortality. Thus, there is a need to study factors associated with this problem. Objective: This study sought to identify risk factors associated with the abandonment of therapy by patients with multidrug-resistant tuberculosis in the Peruvian region of Callao. Materials and methods: We conducted an analytical case-control study (cases=80; controls=180) in patients under treatment from January 1st, 2010, to December 31, 2012. Risk factors were identified using logistic regression; odds ratios (OR) and 95% confidence intervals (CI) were calculated. Results: The multivariate analysis identified the following risk factors: Being unaware of the disease (OR=23.10; 95% CI 3.6-36.79; p=0.002); not believing in healing (OR=117.34; 95% CI 13.57-124.6; p=0.000); not having social support (OR=19.16; 95% CI 1.32-27.77; p=0.030); considering the hours of attention to be inadequate (OR=78.13; 95% CI 4.84-125.97; p=0.002), and not receiving laboratory reports (OR=46.13; 95% CI 2.85-74.77; p=0.007). Conclusion: Health services must focus on the early detection of conditions that may represent risk factors to proactively implement effective, rapid and high-impact interventions.

Characterization of clinical isolates of Mycobacterium tuberculosis from indigenous peoples of Colombia / Caracterización de aislamientos clínicos de Mycobacterium tuberculosis de pueblos indígenas de Colombia

ABSTRACT Introduction: Tuberculosis continues to be a public health priority. Indigenous peoples are vulnerable groups with cultural determinants that increase the risk of the disease. Objective: To determine molecular epidemiology and phenotypical features and of Mycobacterium tuberculosis isolates from indigenous people in Colombia during the period from 2009 to 2014. Materials and methods: We conducted an analytical observational study; we analyzed 234 isolates to determine their patterns of sensitivity to antituberculosis drugs and their molecular structures by spoligotyping. Results: The isolates came from 41 indigenous groups, predominantly the Wayúu (13.10%) and Emberá Chamí (11.35%). We found 102 spoligotypes distributed among seven genetic families (37.2% LAM, 15.8% Haarlem, 8.1% T, 3.4% U, 2.6% S, 2.1% X, and 0.9%, Beijing). The association analysis showed that the non-clustered isolates were related to prior treatment, relapse, orphan spoligotypes, and the Beijing family. The H family presented an association with the Arhuaco and Camëntŝá indigenous groups, the U family was associated with the Wounaan group, and the T family was associated with the Motilón Barí group. Conclusions: This is the first national study on M. tuberculosis characterization in indigenous groups. The study evidenced that diagnosis in indigenous people is late. We described 53% of orphan patterns that could be typical of the Colombian indigenous population. The high percentage of grouping by spoligotyping (62%) could indicate cases of active transmission, a situation that should be corroborated using a second genotyping marker. A new Beijing spoligotype (Beijing-like SIT 406) was identified in Colombia.

RESUMEN Introducción. La tuberculosis es prioridad de salud pública. Los pueblos indígenas son vulnerables debido a los factores culturales determinantes que aumentan el riesgo de tuberculosis. Objetivo. Determinar la epidemiologia molecular y las características fenotípicas de los aislamientos de Mycobacterium tuberculosis de pueblos indígenas de Colombia entre 2009 y 2014. Materiales y métodos. Se hizo un estudio observacional analítico; se analizaron 234 aislamientos para determinar la sensibilidad a los fármacos antituberculosos y la estructura molecular usando spoligotyping. La información epidemiológica se recolectó utilizando el formato único de vigilancia de micobacterias. Resultados. Los aislamientos provenían de 41 grupos indígenas, principalmente los wayúu (13,10 %) y emberá chamí (11,35 %). Se encontraron 102 genotipos distribuidos en siete familias genéticas (37,2 %, LAM; 15,8 %, Haarlem; 8,1 %, T; 3,4 %, U; 2,6 %, S; 2,1 %, X, y 0,9%, Beijing). El análisis de asociación mostró que los aislamientos no agrupados se asociaron con el tratamiento previo, las recaídas, los genotipos huérfanos y la familia Beijing. La familia H presentó una asociación con los grupos indígenas arhuaco y camëntŝá, la familia U se asoció con el grupo wounaan y la familia T con el grupo motilón barí. Conclusiones. Este es el primer estudio nacional de caracterización de M. tuberculosis en grupos indígenas. Se evidenció que el diagnóstico en indígenas es tardío, y que 53 % de los patrones huérfanos podrían ser típicos de la población indígena colombiana. El alto porcentaje de agrupamiento por spoligotyping (62%) podría indicar casos de transmisión activa, una situación que debe ser corroborada usando un segundo marcador de genotipificación. Se identificó un nuevo genotipo (Beijing-like SIT 406) en Colombia.

Vigilancia por el laboratorio de la tuberculosis resistente en menores de 15 años, Colombia, 2010 a 2015 / Resistant tuberculosis in children under 15 years of age, Colombia 2010-2015

Resumen Introducción. La tuberculosis en los niños es un reflejo de transmisión reciente en la comunidad. Se estima que en el mundo cada año un millón de niños enferma por esta causa; en Colombia se notificaron 291 casos en el 2015. Objetivo. Actualizar la información obtenida de las actividades de vigilancia por el laboratorio de la farmacorresistencia del bacilo Mycobacterium tuberculosis en menores de 15 años en Colombia entre el 2010 y el 2015. Materiales y métodos. Se llevó a cabo un estudio retrospectivo de corte transversal. Se estudiaron las variables de procedencia, sexo, edad, tipo de tuberculosis y estado de HIV en los casos sensibles y resistentes. Estos se clasificaron como caso nuevo sin tratamiento o caso previamente tratado para analizar el perfil de resistencia a fármacos de primera y segunda línea. Resultados. De los 3.440 casos notificados, en el 16,4 % se practicó la prueba de sensibilidad. El 50,6 % eran mujeres, la forma pulmonar se presentó en el 70,6 % y el 1,4 % presentó coinfección de tuberculosis y HIV. Se estudiaron 565 casos, de los cuales 503 (89,0 %) eran nuevos: el 3,9 % con tuberculosis multirresistente y el 9,5 % con resistencia global. Los previamente tratados fueron 62 (10,9 %), 4,8 % con multirresistencia y 19,3 % con resistencia global. No se evidenciaron diferencias estadísticamente significativas en los años estudiados. La proporción de tuberculosis extremadamente resistente en los casos nuevos evaluados fue de 9,0 %. Conclusiones. Es necesario que el Ministerio de Salud y Protección Social y el Instituto Nacional de Salud promuevan el uso de pruebas diagnósticas rápidas y muy sensibles, como las moleculares recomendadas por la Organización Mundial de la Salud.

Abstract Introduction: Tuberculosis in children is a recent transmission reflection in the community. It is estimated that every year one million children get sick in the world because of this. In Colombia, 291 cases were notified in 2015. Objective: To update the information obtained from the surveillance activities of the drug-resistance laboratory in children younger than 15 years of age in Colombia between 2010 and 2015. Materials and methods: This was a cross-sectional retrospective study. We studied the variables of origin, gender, age, type of tuberculosis, and HIV status in sensitive and resistant cases. We classified them according to their treatment background between new and previously treated to analyze their first and second line drug resistance profile. Results: From the notified cases, 16.4 % had a sensitivity test. 50.6 % were women, the pulmonary form was present in 70.6% cases, and 1.4 % presented with tuberculosis/HIV coinfection. We studied 565 cases, from which 503 (89.1 %) were new, presenting with multidrug-resistant tuberculosis, and a global resistance of 3.9 % and 9.5 %, respectively. From them, 62 had been previously treated (10.9 %), with 4.8 % and 19.3 % multidrug resistance and global resistance, respectively. There was no evidence of statistically significant differences during the studied years. Extremely resistant tuberculosis in new cases was 9.0 %. Conclusions: It is necessary for the Ministerio de Salud y Protección Social and the Instituto Nacional de Salud to promote the use of faster and more sensitive diagnostic tests such as the molecular ones recommended by the World Health Organization.