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Aim: Tuberculous meningitis (TBM) is one of the most severe clinical forms of tuberculosis (TB). Since epidemiological studies can contribute to TB control, we conducted a review and meta-analysis of epidemiological publications of adults TBM cases in countries with high incidence of TB.Materials & methods: The search resulted in 11,855 articles, in which 21 ultimately were included in our review and 15 in our meta-analysis.Results: TBM mortality was 25% with death rates of 70% in Africa. The review showed different and non-concordant diagnostic techniques and treatment schemes.Conclusion: Adults living in the African region are at high risk of death from TBM, highlighting an urgent need of guidelines to support diagnosis and treatment, and ultimately, to reduce mortality.
Tuberculosis (TB) is a disease that mostly affects the lungs. It can also affect other organs. When TB affects the brain and spinal cord, it is called tuberculous meningitis (TBM). We looked to analyze the traits of the adults with TBM that live in countries with a high number of cases of TB. We searched scientific publications that studied these populations to find information that may help to control the disease. The death rate of TBM was 25%, reaching up to 70% in Africa. We found some disparities regarding diagnosis and treatment. Adults living in Africa have a higher risk of dying from TBM. We need guidelines about the diagnosis and treatment of TBM to help reduce TBM deaths in these countries.
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Tuberculosis is a disease caused by Mycobacterium tuberculosis, with high mortality rates and an extended treatment that causes severe adverse effects, besides the emergence of resistant bacteria. Therefore, the search for new compounds with anti-M. tuberculosis activity has considerably increased in recent years. In this context, benzohydrazones are significant compounds that have antifungal and antibacterial action. This study aimed at evaluating the in vitro activity of 18 benzohydrazones against M. tuberculosis. Compounds' cytotoxicity, inhibition of M. tuberculosis efflux pumps, and in silico absorption, distribution, metabolism, excretion, and toxicity (ADMET) assays were also performed. In general, the minimum inhibitory concentration values for the standard M. tuberculosis H37Rv strain ranged from 7.8 to 250 µg/mL, and some compounds were not toxic to any of the cells tested (IC50 ranged from 18.0 to 302.5 µg/mL). In addition, compounds (4) and (7) showed to be possible efflux pump inhibitors. In ADMET assays, all benzohydrazones had high gastrointestinal absorption. Most of the compounds were able to overcome the blood-brain barrier, and no compounds had irritant or tumorigenic effects. Compounds (1), (3), (9), (12), and (15) stood out for showing good activities, both in vitro and in silico assays.
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Antituberculosos/farmacología , Hidrazonas/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Pruebas de Sensibilidad MicrobianaRESUMEN
BACKGROUND: For more than 60 years, the lack of new anti-tuberculosis drugs and the increase of resistant Mycobacterium tuberculosis lineages exhibit a therapeutic challenge, demanding new options for the treatment of resistant tuberculosis. OBJECTIVE: Herein, we determined the (i) activities of (-)-camphene and its derivatives and (ii) combinatory effect with pyrazinamide (PZA) against Mycobacterium tuberculosis in acidic pH and (iii) cytotoxicity on VERO cells. METHODS: The activity of (-)-camphene and its 15 derivatives was determined in M. tuberculosis H37Rv in culture medium at pH 6.0 by Resazurin Microtiter Assay Plate (REMA). The activity and combinatory study of three (-)-camphene derivatives with PZA was carried out on seven multidrugresistant (MDR) clinical isolates by REMA and Checkerboard, respectively. The assay of 3-(4,5- dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) bromide in VERO cells was used to determine the derivatives' cytotoxicity. RESULTS: Four (-)-camphene derivatives, (4), (5a) (5d) and (5h), showed a reduction in the MIC value at pH 6.0 compared to the MIC detected at pH 6.8 in M. tuberculosis H37Rv and multidrug resistant clinical isolates. Three (-)-camphene derivatives, (4), (5d) and (5h), showed synergistic effect (FICI ≤ 0.5) combined with PZA and were more selective for M. tuberculosis than VERO cell (selective index from 7.7 to 84.2). CONCLUSION: Three (-)-camphene derivatives have shown to be promising anti-TB molecule scaffolds due to their low MIC values in acidic pH against MDR M. tuberculosis clinical isolates, synergism with PZA and low cytotoxicity.
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Antituberculosos/farmacología , Monoterpenos Bicíclicos/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Animales , Antituberculosos/química , Antituberculosos/toxicidad , Monoterpenos Bicíclicos/química , Monoterpenos Bicíclicos/toxicidad , Chlorocebus aethiops , Concentración de Iones de Hidrógeno , Pruebas de Sensibilidad Microbiana , Estereoisomerismo , Células VeroRESUMEN
Background: The treatment of multidrug-resistant tuberculosis (MDR-TB) is a challenge to be overcome. The increase of resistant isolates associated with serious side effects during therapy leads to the search for substances that have anti-TB activity, which make treatment less toxic, and also act in the macrophage acidic environment promoted by the infection. Objective: The aim of this study was to investigate lapachol and ß-lapachone activities in combination with other drugs against Mycobacterium tuberculosis at neutral and acidic pH and its cytotoxicity. Design: Inhibitory and bactericidal activities against M. tuberculosis and clinical isolates were determined. Drug combination and cytotoxicity assay were carried out using standard TB drugs and/or N-acetylcysteine (NAC). Results: Both naphthoquinones presented activity against MDR clinical isolates. The combinations with the first-line TB drugs demonstrated an additive effect and ß-lapachone+NAC were synergic against H37Rv. Lapachol activity at acidic pH and its association with NAC improved the selectivity index. Lapachol and ß-lapachone produced cell morphological changes in bacilli at pH 6.0 and 6.8, respectively. Conclusion: Lapachol revealed promising anti-TB activity, especially associated with NAC.
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Antituberculosos/farmacología , Naftoquinonas/farmacología , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Antituberculosos/administración & dosificación , Supervivencia Celular , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Quimioterapia Combinada , Humanos , Concentración de Iones de Hidrógeno , Macrófagos/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Naftoquinonas/administración & dosificaciónRESUMEN
A series of methyl ß-carboline carboxylates (2a-g) and of imide-ß-carboline derivatives containing the phthalimide (4a-g), maleimide (5b, g) and succinimide (6b, e, g) moiety were synthesized, and evaluated for their activity against Mycobacterium tuberculosis H37Rv. The most active ß-carboline derivatives against the reference strain were assayed for their cytotoxicity and the activity against resistant M. tuberculosis clinical isolates. Farther, structure-activity relationship (SAR) studies were carried out using the three and four-dimensional approaches for starting to understand the way of ß-carboline activity in M. tuberculosis. All 19 ß-carboline derivatives were assayed, firstly, by determining the minimum inhibitory concentration (MIC) using resazurin microtiter assay plate (REMA) in M. tuberculosis H37Rv. Then, five derivatives (2c, 4a, 4e, 4g, 6g), which showed MIC ≤ 125 µg/mL, were assayed in nine resistant M. tuberculosis clinical isolates (five MDR, three isoniazid monoresistant and one isoniazid plus streptomycin resistant). The MIC values against the resistant clinical isolates ranged from 31.25 to >250 µg/mL. All five derivatives were non-cytotoxic to the VERO cell line, determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, at the tested concentration (selectivity index ranged from <1.74 to 14.4). Our study demonstrated that (2c) and (6g) derivatives had better anti-M. tuberculosis activity, especially against resistant clinical isolates, what makes them scaffold candidates for further investigations about their anti-tuberculosis activity. The SAR study conducted with the 19 ß-carboline derivatives showed the importance of steric effects for the synthesized ß-carbolines against M tuberculosis, and these models can be used for future proposition of new derivatives, increasing the chances of obtaining potentially anti-tuberculosis compounds.
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Antituberculosos/farmacología , Carbolinas/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Animales , Antituberculosos/síntesis química , Antituberculosos/química , Carbolinas/síntesis química , Carbolinas/química , Chlorocebus aethiops , Relación Dosis-Respuesta a Droga , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Relación Estructura-Actividad Cuantitativa , Células VeroRESUMEN
Tuberculosis (TB) is an important public health problem worldwide and the emergence of multidrug-resistant (MDR) TB and extensively drug-resistant (XDR) TB worsened the global context. The resistance in Mycobacterium tuberculosis, the causative agent of TB, can partially derive from efflux pumps (EPs) activity in plasma membrane. Due to the recent discovery of piperine (PIP), an organic alkaloid compound, increasing the bioavailability of various drugs, the current assay evaluated the combined activity of PIP and anti-TB drugs in susceptible and resistant M. tuberculosis clinical isolates. The minimum inhibitory concentrations for isoniazid, rifampicin, ethambutol, streptomycin and PIP were determined by resazurin microtiter assay and the combined effects of anti-TB drugs with PIP determined by resazurin drug combination microtiter assay and time-kill curve. The efflux pump inhibitor activity of PIP was determined by bromide accumulation assay and cytotoxicity carried out in VERO cells and J774. A1 macrophages. PIP showed to have EPI activity and RIF + PIP and SM + PIP combinations showed synergistic effect, but low effect in enhancing the killing in M. tuberculosis H37Rv and in the clinical isolates studied, which had different resistance profiles. Future studies are needed to further clarify the importance of PIP as an adjunctive drug in the therapy against TB.
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Alcaloides/farmacología , Antituberculosos/farmacología , Proteínas Bacterianas/efectos de los fármacos , Benzodioxoles/farmacología , Proteínas de Transporte de Membrana/efectos de los fármacos , Mycobacterium tuberculosis/efectos de los fármacos , Piperidinas/farmacología , Alcamidas Poliinsaturadas/farmacología , Alcaloides/metabolismo , Animales , Antituberculosos/metabolismo , Proteínas Bacterianas/metabolismo , Benzodioxoles/metabolismo , Chlorocebus aethiops , Farmacorresistencia Bacteriana/efectos de los fármacos , Sinergismo Farmacológico , Quimioterapia Combinada , Proteínas de Transporte de Membrana/metabolismo , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana/efectos de los fármacos , Mycobacterium tuberculosis/crecimiento & desarrollo , Mycobacterium tuberculosis/metabolismo , Piperidinas/metabolismo , Alcamidas Poliinsaturadas/metabolismo , Células VeroRESUMEN
The high tuberculosis (TB) incidence rates, the closeness of the cities and the high migration flux on the Brazil/Paraguay/Argentina border deserves an in-depth study, using Mycobacterial Interspersed Repetitive Unit (MIRU) and Spoligotyping genetic markers to explore the impact of the Mycobacterium tuberculosis RDRio lineage on disease transmission and resistance to anti-TB drugs in this setting. Although without the totality of M. tuberculosis isolates causing TB in this studied setting, a number of 97 isolates obtained from sputa samples culture of patients with confirmed TB, from 2013 to 2015, were submitted to 24 loci MIRU, Spoligotyping, detection of RDRio lineage and detection of mutation related to isoniazid and rifampicin resistance by MTBDRplus/DNA STRIP. In this sample, it was observed high clonal variability of circulating M. tuberculosis isolates causing TB in Brazilian cities bordering Paraguay and Argentina. The percentage of RDRio lineage causing TB in this setting was 15.46%, and lower than the detected in different areas of Brazil. According to 24 loci MIRU, the major MIRU International Type (MIT) related with RDRio lineage were MIT 26, MIT 738, MIT 601 with four, two and one isolates, respectively. Eight isolates with RDRio marker were classified as orphans. The mainly Spoligofamily related with RDRio lineage was LAM1 and LAM9 and no relationship between RDRio lineage and resistance in M. tuberculosis isolates circulating in this setting could be established. This work is pioneer in studying the dynamics of RDRio lineage transmission on the Brazil/Paraguay/Argentina border and deserves further studies to analyze the real contribution of the RDRio lineage in outbreaks and the risk of significant development of MDR-TB in the setting studied.
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Mycobacterium tuberculosis/genética , Tuberculosis/microbiología , Argentina/epidemiología , Técnicas de Tipificación Bacteriana/métodos , Brasil/epidemiología , Farmacorresistencia Bacteriana Múltiple/genética , Genes Bacterianos , Marcadores Genéticos , Humanos , Incidencia , Pruebas de Sensibilidad Microbiana/métodos , Mutación , Mycobacterium tuberculosis/clasificación , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/aislamiento & purificación , Paraguay/epidemiología , Tuberculosis/epidemiología , Tuberculosis/transmisiónRESUMEN
Tuberculosis (TB) is an infectious disease in which the molecular typing methods allow to have important information about the dynamics of transmission and to assist properly in disease control. Although the ERIC-PCR (Enterobacterial repetitive intergenic consensus-PCR) assay is fast and easy to perform, scarce studies have reported its use in epidemiological studies in TB outbreaks. In this study, we aimed to genotype Mycobacterium tuberculosis and M. bovis isolates by ERIC-PCR and compare its discriminatory power with two other classically used methods: 12 loci-MIRU (Mycobacterial Interspersed Repetitive Units) and Spoligotyping. The M. tuberculosis isolates studied were from northwestern and southwestern and M. bovis from northwestern Parana, Brazil. ERIC-PCR rendered banding patterns with great diversity (1 to 12 bands) of molecular sizes, ranging from 100 to 1600 bp. ERIC-PCR showed to be fast, simple and affordable to differentiate isolates. ERIC-PCR would be an important tool in the epidemiology of TB as screening in case of outbreak, which demands rapid intervention. However if any doubt persist, as it may occur with the application of only one genotypic method, other genotyping methods should be applied and carefully interpreted, always with additional epidemiological information.
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Reacción en Cadena de la Polimerasa , Mycobacterium bovis/aislamiento & purificación , Mycobacterium tuberculosis/aislamiento & purificación , Tuberculosis/fisiopatología , Epidemiología , Tipificación Molecular/métodos , Técnicas de Genotipaje/métodosRESUMEN
Essential oils from fresh Piperaceae leaves were obtained by hydrodistillation and analyzed by gas chromatography mass spectrometry (GC-MS), and a total of 68 components were identified. Principal components analysis results showed a chemical variability between species, with sesquiterpene compounds predominating in the majority of species analyzed. The composition of the essential oil of Piper mosenii was described for the first time. The cytotoxicity of the essential oils was evaluated in peritoneal macrophages and the oils of P. rivinoides, P. arboretum, and P. aduncum exhibited the highest values, with cytotoxic concentration at 50% (CC50) > 200 µg/mL. Both P. diospyrifolium and P. aduncum displayed activity against Leishmania amazonensis, and were more selective for the parasite than for the macrophages, with a selectivity index (SI) of 2.35 and >5.52, respectively. These SI values were greater than the 1 for the standard drug pentamidine. The antileishmanial activity of the essential oils of P. diospyrifolium and P. aduncum was described for the first time. P. rivinoides, P. cernuum, and P. diospyrifolium displayed moderate activity against the Mycobacterium tuberculosis H37Rv bacillus, with a minimum inhibitory concentration (MIC) of 125 µg/mL. These results are relevant and suggests their potential for therapeutic purposes. Nevertheless, further studies are required to explain the exact mechanism of action of these essential oils.
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Antiprotozoarios/farmacología , Antituberculosos/farmacología , Leishmania/efectos de los fármacos , Mycobacterium tuberculosis/efectos de los fármacos , Aceites Volátiles/farmacología , Piper/química , Aceites de Plantas/farmacología , Animales , Antiprotozoarios/química , Antituberculosos/química , Cromatografía de Gases y Espectrometría de Masas , Macrófagos Peritoneales/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/química , Pruebas de Sensibilidad Parasitaria , Hojas de la Planta/química , Aceites de Plantas/química , Análisis de Componente PrincipalRESUMEN
We report the in vitro drugs interaction by the resazurin drugs combination microtiter assay (REDCA) of amoxicillin (AMO)/clavulanate (CLAV) with isoniazid (INH), ethambutol (EMB), and rifampicin (RIF) against susceptible and resistant Mycobacterium tuberculosis isolates. The addition of AMO/CLAV to classical antituberculosis drugs should be explored as a promising alternative for the treatment of resistant tuberculosis (TB).
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Amoxicilina/farmacología , Antituberculosos/farmacología , Ácido Clavulánico/farmacología , Etambutol/farmacología , Isoniazida/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Rifampin/farmacología , Farmacorresistencia Bacteriana Múltiple , Humanos , Pruebas de Sensibilidad Microbiana , Mycobacterium tuberculosis/aislamiento & purificación , Oxazinas/análisis , Xantenos/análisisRESUMEN
ABSTRACT Leprosy is a neglected tropical disease and an important public health problem, especially in developing countries. It is a chronic infectious disease that is caused by Mycobacterium leprae, which has a predilection for the skin and peripheral nerves. Although it has low sensitivity, slit-skin smear (SSS) remains the conventional auxiliary laboratory technique for the clinical diagnosis of leprosy. Polymerase chain reaction (PCR) is a molecular biology technique that holds promise as a simple and sensitive diagnostic tool. In the present study, the performance of two PCR methods, using different targets, PCR-LP and PCR-P, were compared with SSS with regard to leprosy diagnosis in a reference laboratory. M. leprae DNA was extracted from 106 lymph samples of 40 patients who had clinical suspicion of leprosy. The samples were subjected to both PCR techniques and SSS. Amplification of the human b-globin gene was used as PCR inhibitor control. The specificity of both PCR techniques was 100%, and sensitivity was 0.007 and 0.015 µg/ml for PCR-LP and PCR-P, respectively. No significant difference was found between either the PCR-LP or PCR-P results and SSS results (p > 0.05). Although PCR is not yet a replacement for SSS in the diagnosis of leprosy, this technique may be used as an efficient auxiliary tool for early detection of the disease, especially in endemic regions. This strategy may also be useful in cases in which SSS results are negative (e.g., in paucibacillary patients) and cases in which skin biopsy cannot be performed.
RESUMO A hanseníase é uma doença tropical negligenciada e ainda um importante problema de saúde pública, especialmente nos países em desenvolvimento. É uma doença infecciosa crônica causada pelo Mycobacterium leprae, que tem predileção pela pele e nervos periféricos. Embora com baixa sensibilidade, o esfregaço de linfa (SSS) continua sendo o método laboratorial convencional auxiliar no diagnóstico clínico da hanseníase. A biologia molecular representada pela Reação em Cadeia da Polimerase (PCR) trouxe a expectativa de ser uma ferramenta diagnóstica simples e sensível. No presente estudo, o desempenho de dois métodos de PCR usando alvos diferentes, PCR-P e PCR-LP, foi comparado com SSS no diagnóstico da hanseníase em um laboratório de referência. DNA de M. leprae foi extraído de 106 amostras de linfa de 40 pacientes que apresentavam suspeita clínica de hanseníase. As amostras foram submetidas tanto a PCR como SSS. A amplificação do gene humano β-globina foi usada como controle de inibição da PCR. A especificidade de ambas as técnicas de PCR foi de 100% e a sensibilidade foi de 0,007 μg/mL e 0,015 μg/mL para a PCR-P e PCR-LP, respectivamente. Não se observou diferença estatística entre os resultados da PCR-LP e PCR-P, quando comparado com SSS (p > 0,05). Apesar de a PCR ainda não substituir o SSS no diagnóstico da hanseníase, esta técnica pode ser usada como ferramenta auxiliar eficiente para a detecção precoce da doença, especialmente em regiões endêmicas. Esta estratégia pode também ser útil nos casos em que os resultados de SSS forem negativos (ex. em pacientes paucibacilares) e em casos onde a biópsia da pele não pode ser realizada.
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Humanos , Reacción en Cadena de la Polimerasa , Lepra/diagnóstico , Reacción en Cadena de la Polimerasa/métodos , Mycobacterium lepraeRESUMEN
BACKGROUND: At the triple border Brazil/Paraguay/Argentina there is easy mobility from one city to another for economic and tourism activities. This constant and fast population mobility is mainly to visit Iguazu Falls, in the Iguazu River, on the border of the Brazilian state of Paraná and the Argentina. As the incidence of tuberculosis is high in this setting, our study aimed to establish a first baseline of circulating genotypic lineages of Mycobacterium tuberculosis. METHODOLOGY/PRINCIPAL FINDINGS: This study included 120 patients from 10 cities in southwestern Paraná, Brazil with pulmonary symptoms, from July 2009 to July 2011. Information about sex, age, clinical features and address was collected by reviewing the national tuberculosis notification database. Of these, 96 (80%) isolates were identified as M. tuberculosis and 22 (22.9%) were drug resistant (20, 20.8% INH mono-resistant and 2, 2.1% multidrug-resistant). All isolates were subjected to genotyping by Spoligotyping and MIRU-VNTR typing. The distribution of the isolates analyzed by spoligotyping revealed 30 distinct patterns. The four mainly detected clades were Latin American and Mediterranean (LAM), ill-defined T, Haarlem (H) and S. The MIRU-VNTR showed 85 distinct patterns. Spoligotyping combined to MIRU-VNTR allowed 90 distinct patterns. CONCLUSIONS/SIGNIFICANCE: Our study demonstrated that there is significant molecular diversity in circulating M. tuberculosis, with predominance of the LAM and T clades in cities of southwestern Paraná, Brazil, bordering Argentina and Paraguay.