Tuberculosis por Mycobacterium africanum multirresistente: Caso clinico pediatrico / Tuberculosis by multiresistant Mycobacterium africanum: Pediatric clinical case

La tuberculosis, considerada desde 2003 por la Organización Mundial de la Salud una emergencia global de salud, provoca una mortalidad anual de alrededor de 2 millones de personas, fundamentalmente, en países en vías de desarrollo. En la población pediátrica española, la incidencia es de 5 casos/100 000 niños de entre 5 y 14 años y 13 casos/100 000 niños de entre 0 y 4 años. La infección se transmite por vía respiratoria por enfermos bacilíferos. Los niños eliminan escasos bacilos en secreciones respiratorias y no suelen transmitir la infección. En España, el porcentaje de resistencias a isoniazida en la población general es de 5% y es superior en la población inmigrante, lo cual es importante tener en cuenta para el tratamiento de los casos. Se presenta un caso de tuberculosis por Mycobacterium africanum multirresistente al tratamiento, con evolución satisfactoria posterior a la terapia múltiple.

Tuberculosis, considered since 2003 by the World Health Organization a global health emergency, causes annual mortality of approximately 2 million people, mainly in developing countries. In the Spanish pediatric population, the incidence is 5 cases/100 000 children between 5 and 14 years and 13 cases/100 000 children between 0 and 4 years. The infection is transmitted through the respiratory tract by baciliferous patients. Children eliminate few bacilli in respiratory secretions and do not usually transmit the infection. In Spain, the resistance to isoniazid in the general population is 5%, being higher in the immigrant population, which is important to take into account for the treatment of cases. A case of tuberculosis due to Mycobacterium africanum multiresistant to treatment is presented, with satisfactory evolution after multiple therapy.

Lack of association between rrl and erm(41) mutations and clarithromycin resistance in Mycobacterium abscessus complex

BACKGROUND Mycobacterium abscessus complex (MABC) includes species with high resistance rates among mycobacterial pathogens. In fact, MABC infections may not respond to clarithromycin treatment, which has historically been very effective against MABC infection. Molecular markers have been proposed to detect both acquired (rrl polymorphisms) and inducible (erm(41) polymorphisms) clarithromycin resistance in MABC isolates. OBJECTIVES This study aimed to evaluate the susceptibility profile and molecular markers of clarithromycin resistance in MABC. METHODS The clarithromycin susceptibility profile was determined by broth microdilution with reads on days 3, 5, 7 and 14. Mutations in the rrl and erm(41) genes were evaluated by polymerase chain reaction (PCR) using specific primers, followed by sequencing. FINDINGS A total of 14 M. abscessus subsp. abscessus isolates and 28 M. abscessus subsp. massiliense isolates were evaluated, and clarithromycin resistance was observed in all isolates for up to three days of incubation. None of the 42 isolates exhibited a point mutation in the rrl gene, while all the isolates had a T28 polymorphism in the erm(41) gene. Moreover, all 28 M. abscessus subsp. massiliense isolates had a deletion in the erm(41) gene. MAIN CONCLUSIONS While all the MABC isolates exhibited acquired clarithromycin resistance, no isolates exhibited a point mutation in the rrl gene in this study. The M. abscessus subsp. massiliense isolates demonstrated clarithromycin resistance, which is an uncommon phenotype. The molecular data for the rrl and erm(41) genes were not consistent with the phenotypic test results of clarithromycin susceptibility, indicating a lack of correlation between molecular clarithromycin resistance markers for both acquired and inducible resistance.

Clinical challenges in the era of multiple and extensively drug-resistant tuberculosis / Retos clínicos en la era de la tuberculosis multirresistente y extensamente resistente / Desafios clínicos na era da tuberculose com resistência ampla a múltiplos medicamentos

ABSTRACT In 2014, there were 480 000 new cases of multidrug-resistant tuberculosis (MDR-TB) around the world, but only 25% of them were diagnosed and reported. Drug resistance in TB is necessarily a laboratory diagnosis. An urgent priority in everyday practice is to diagnose tuberculosis and rule out drug resistance as quickly and as accurately as possible. However, worldwide, only 12% of new bacteriologically confirmed TB cases and 58% of previously treated TB cases were tested for drug resistance in 2014. New tools for diagnosis of TB and drug-resistant TB have been introduced for clinical practice during the past decade. Those new tools can detect and identify drug resistance to antituberculosis drugs in less than 24 hours, and they should be urgently integrated into clinical practice, especially in high-burden regions. Ongoing transmission of TB generates new infections, and this infected population is the inexhaustible source of new TB cases. If we are really determined to stop the global TB epidemic, we need to treat active cases and also halt the transmission of the infection. The only strategy for preventing the development of active disease in individuals with subclinical infection is to give treatment for this latent infection. Global control of TB requires a huge investment of funds to address current detection and treatment gaps. We must reconsider our current strategy and combine social components with biomedical interventions. This will require the development of alliances between government and civil society, as well as leadership and true political commitment at the highest level of government.

RESUMEN En el 2014 se presentaron 480 000 nuevos casos de tuberculosis multirresistente, pero solo se diagnosticó y notificó 25% de ellos. La farmacorresistencia en la tuberculosis se diagnostica necesariamente por medio de pruebas de laboratorio. En la práctica clínica diaria resulta urgente y prioritario poder diagnosticar la tuberculosis y descartar la farmacorresistencia con la mayor rapidez y exactitud posibles. Sin embargo, en todo el mundo, apenas 12% de los nuevos casos de tuberculosis bacteriológicamente confirmados y 58% de los casos ya tratados se sometieron a prueba de farmacorresistencia en el 2014. En los diez últimos años se han dado a conocer nuevas herramientas para el diagnóstico de la tuberculosis y la tuberculosis farmacorresistente en la práctica clínica. Esas herramientas nuevas permiten detectar e identificar la resistencia a medicamentos antituberculosos en menos de 24 horas, por lo que deberían integrarse urgentemente a la práctica clínica, especialmente en las regiones con una carga de enfermedad alta. La persistencia de la transmisión de la tuberculosis genera nuevas infecciones, y la población infectada es una fuente inagotable de nuevos casos de esta enfermedad. Si estamos realmente decididos a poner fin a la epidemia mundial de la tuberculosis, tenemos que tratar los casos activos y también detener la transmisión de la infección. La única estrategia para prevenir la aparición de la enfermedad activa en personas con infección subclínica es administrar tratamiento contra esta infección latente. El control mundial de la tuberculosis requiere una enorme inversión de fondos para cerrar las brechas existentes en la detección y el tratamiento. Debemos reconsiderar nuestra estrategia actual y combinar los componentes sociales con las intervenciones biomédicas. Esto obliga a conformar alianzas entre el gobierno y la sociedad civil, y requiere del liderazgo y de un verdadero compromiso político de las más altas instancias gubernamentales.

RESUMO Em 2014, houve 480 mil novos casos de tuberculose (TB) resistente a múltiplos medicamentos, porém apenas 25% foram diagnosticados e notificados. A resistência aos medicamentos na TB requer necessariamente que seja feito um diagnóstico laboratorial. É prioridade na prática clínica diária diagnosticar a TB e descartar a resistência aos medicamentos o mais rápido e com maior precisão possível. Porém, em 2014, o teste da resistência aos medicamentos foi realizado mundialmente em apenas 12% dos novos casos de TB com confirmação bacteriológica e em 58% dos casos de TB com tratamento anterior. Novas ferramentas para o diagnóstico de TB e TB resistente a múltiplos a medicamentos foram introduzidas na prática clínica na última década. São ferramentas com capacidade de detectar e identificar a resistência aos medicamentos antituberculose em menos de 24 horas e, portanto, é imprescindível que sejam integradas à prática clínica, sobretudo em regiões de elevada carga da doença. A transmissão contínua da TB causa novas infecções, sendo a população infectada uma fonte inesgotável de novos casos da doença. Se estivermos realmente determinados a conter a epidemia global de TB, é preciso tratar os casos ativos e interromper a transmissão da infecção. A única estratégia para prevenir o surgimento de doença ativa em indivíduos com infecção subclínica é o tratamento da infecção latente. O controle global da TB requer um enorme investimento financeiro para sanar as falhas atuais de detecção e tratamento da doença. A estratégia atual deve ser reexaminada e combinar componentes sociais e intervenções biomédicas. Faz-se necessário forjar alianças entre o governo e a sociedade civil bem como assumir a liderança e o firme compromisso no mais alto nível político.

Anti-fungal and anti-mycobacterial activity of plants

Severe fungal infections, particularly those caused by Candida spp, have increased in recent decades and are associated with an extremely high rate of morbidity and mortality. Since plants are an important source of potentially bioactive compounds, in this work the antifungal activity of the methanol extracts of 10 plants [Acacia rigidula, Buddleja cordata, Cephalanthus occidentalis, Juglans nigra, Parkinsonia aculeata, Parthenium hysterophorus, Quercus canbyi, Ricinus communis, Salvia coccinea and Teucrium bicolor] were evaluated. The activity was evaluated according to the micro dilution assay described in CLSI M27-A protocol using some clinical isolates of different species of Candida [C. albicans, C. parapsilosis, C. tropicalis, C. krusei and C. glabrata]. All extracts showed MIC values

Características clínicas, factores de riesgo y perfil de susceptibilidad de las infecciones por micobacterias documentadas por cultivo, en un hospital universitario de alta complejidad en Medellín (Colombia) / Clinical features, risk factors and susceptibility profile of mycobacterial infections documented by culture in a university hospital of high complexity in Medellin (Colombia)

Introduction: Tuberculosis (TB) remains an entity of high prevalence and mortality worldwide. The rising drug resistance is a public health problem. Besides, non-tuberculosis mycobacterial (NTM) infections are described with increasing frequency in areas of high prevalence of TB. Objectives: To determine epidemiological, clinical and microbiological characteristics of mycobacterial infections documented by culture. Materials and Methods: An observational, descriptive study in hospitalized patients. Results: M. tuberculosis complex was identified in 90,9% of 187 patients; 9,1% had NTM, 64% were male and the mean age was 40 years (range 1-88 years). The main co-morbidities were HIV / AIDS (23.5%), use of corticosteroids (13.3%) and chronic kidney disease (9.6%). Clinical forms were pulmonary (56.6%), extra-pulmonary (23.9%) and disseminated (19.2 The most common extra-pulmonary compromise was nodal (7.4%) and gastrointestinal (7%). 10.6% of M. tuberculosis were multi-drugresistant (MDR) and 2.12% had extended drug resistance (XDR). Mycobacterium avium andM. abscessus were the most frequent NTM. Overall mortality was 10%. Conclusions: In our study immune suppression is the main risk factor for extrapulmonary and disseminated disease. Resistance, MDR and XDR is higher in inpatients with TB. MNT infections are not uncommon in our country.

Introducción: Tuberculosis (TBC) es aún una entidad de alta prevalencia y mortalidad en el mundo. La resistencia ascendente a fármacos es un problema de salud pública. Además se describen con mayor frecuencia infecciones por micobacterias no tuberculosas (MNT) en áreas de alta prevalencia de TBC. Objetivos: Determinar características epidemiológicas, clínicas y microbiológicas de las infecciones por micobacterias documentadas por cultivo. Materiales y Métodos: Estudio observacional, descriptivo, en pacientes hospitalizados. Resultados: De 187 pacientes, en 90,9% se identificó complejo M. tuberculosis y en 9,1% MNT; 64% fueron hombres. Edad promedio 40 años (rango 1-88 años). Las principales co-morbilidades fueron infección por VIH/SIDA (23,5%), uso de corticoesteroides (13,3%) y enfermedad renal crónica (9,6%). Las formas clínicas fueron pulmonares (56,6%), extra-pulmonares (23,9%) y diseminadas (19,2%). El compromiso extra-pulmonar más frecuente fue ganglionar (7,4%) y gastrointestinal (7%). En M. tuberculosis 10,6% fueron multidrogoresistentes (MDR) y 2,12% con resistencia extendida (XDR). Mycobacterium avium y M. abscessus fueron las MNT más frecuentes. La mortalidad general fue 10%. Conclusiones: Inmuno-supresión es el principal factor de riesgo para enfermedad extrapulmonar y/o diseminada y la resistencia a fármacos en pacientes hospitalizados con TBC es llamativa, con mayor incidencia de MDR y XDR. Las infecciones por MNT no son infrecuentes en nuestro medio.

Evaluation of attimicrobial and cytotoxic activties of plant extracts from souuthern minas gerais cerrado / Avaliacao das atividades antimicrobiana e citotoxica de extratos de plantas do Cerrado do Sul de Minas Gerais

The antimicrobial activity of plant hidroethanolic extracts on bacteria Gram positive, Gram negative, yeasts, Mycobacterium tuberculosis H37 and Mycobacterium bovis was evaluated by using the technique of Agar diffusion and microdilution in broth. Among the extracts evaluated by Agar diffusion, the extract of Bidens pilosa leaf presented the most expressive average of haloes of growth inhibition to the microorganisms, followed by the extract of B. pilosa flower, of Eugenia pyriformis' leaf and seed, of Plinia cauliflora leaf which statistically presented the same average of haloes inhibitory formation on bacteria Gram positive, Gram negative and yeasts. The extracts of Heliconia rostrata did not present activity. Mycobacterium tuberculosis H37 and Mycobacterium bovis (BCG) appeared resistant to all the extracts. The susceptibility profile of Candida albicans and Saccharomyces cerevisiae fungi were compared to one another and to the Gram positive Bacillus subtilis, Enterococcus faecalis and the Gram negative Salmonella typhimurium bacteria (p > 0.05). The evaluation of cytotoxicity was carried out on C6-36 larvae cells of the Aedes albopictus mosquito. The extracts of stem and flower of Heliconia rostrata, leaf and stem of Plinia cauliflora, seed of Anonna crassiflora and stem, flower and root of B. pilosa did not present toxicity in the analyzed concentrations. The highest rates of selectivity appeared in the extracts of stem of A. crassiflora and flower of B. pilosa to Staphylococcus aureus, presenting potential for future studies about a new drug development.

Foi avaliada a atividade antimicrobiana de extratos hidroetanólicos de plantas sobre bactérias Gram positiva, Gram negativa, leveduras, Mycobacterium tuberculosis H37 e Mycobacterium bovis pela técnica de difusão em Agar e microdiluição em caldo. Dentre os extratos avaliados pelo método de difusão em Agar, o extrato da folha de Bidens pilosa apresentou a mais expressiva média de halos de inibição de crescimento frente aos microrganismos, seguido pelo extrato da flor de B. pilosa, da folha e semente de Eugenia pyriformis, da folha de Plinia cauliflora que apresentaram estatisticamente a mesma média de formação de halos inibitórios sobre bactérias Gram positivas, Gram negativas e leveduras. Os extratos de Heliconia rostrata não apresentaram atividade. Mycobacterium tuberculosis H37 e Mycobacterium bovis (BCG) mostraram-se resistentes a todos os extratos. O perfil de sensibilidade dos fungos Candida albicans e Saccharomyces cerevisiae foram comparáveis entre si e entre as bactérias Gram positivas Bacillus subtilis, Enterococcus faecalis e Gram negativa Salmonella typhimurium (p > 0.05). A avaliação da citotoxicidade foi realizada sobre células C6-36 de larvas de mosquito Aedes albopictus. Os extratos de caule e flor de H. rostrata, folha e caule de P. cauliflora, semente de Anonna crassiflora e caule, flor e raiz de B. pilosa não apresentaram toxicidade nas concentrações avaliadas. Os maiores índices de seletividade foram apresentados pelos extratos de caule de A. crassiflora e flor de B. pilosa para Staphylococcus aureus, apresentando potencial para estudos como futuros candidatos a fármacos.

The Drug Resistance Profile of Mycobacterium abscessus Group Strains from Korea

BACKGROUND: Bacteria of the Mycobacterium abscessus group are the second most common pathogens responsible for lung disease caused by nontuberculous mycobacteria in Korea. There is still a lack of studies investigating the genetic mechanisms involved in M. abscessus resistance to antibiotics other than clarithromycin. This study investigated the characteristics of drug resistance exhibited by M. abscessus clinical isolates from Korea. METHODS: We performed drug susceptibility testing for a total of 404 M. abscessus clinical strains. Subspecies were differentiated by molecular biological methods and examined for mutations in drug resistance-related genes. RESULTS: Of the 404 strains examined, 202 (50.00%), 199 (49.26%), and 3 (0.74%) strains were identified as M. abscessus, M. massiliense, and M. bolletii, respectively. Of the 152 clarithromycin-resistant strains, 6 possessed rrl mutations, while 4 of the 30 amikacin-resistant strains contained rrs mutations, and 5 of the 114 quinolone-resistant strains had gyr mutations. All mutant strains had high minimal inhibitory concentration values for the antibiotics. CONCLUSIONS: Our results showed the distribution of the strains with mutations in drug resistance-related genes was low in the M. abscessus group. Furthermore, we performed drug susceptibility testing and sequence analyses to determine the characteristics of these genes in the M. abscessus group.

Mycobacterium massiliense BRA100 strain recovered from postsurgical infections: resistance to high concentrations of glutaraldehyde and alternative solutions for high level disinfection / Mycobacterium massiliense clone BRA100 associado a infecções pós-cirúrgicas: resistência a altas concentrações de glutaraldeído e produtos alternativos para desinfecção de alto nível

PURPOSE: To evaluate the minimum inhibitory concentration (MIC) of GTA against these microorganisms and alternative disinfectants for high-level disinfection (HLD). METHODS: Reference mycobacteria and clinical M. massiliense strains were included in this study. Active cultures were submitted to susceptibility qualitative tests with GTA dilutions (ranging from 1.5 percent to 8 percent), and commercial orthophthaldehyde (OPA) and peracetic acid (PA) - based solutions, during the period of exposure as recommended by National Agency of Sanitary Surveillance for HLD. RESULTS: All reference and M. massiliense non-BRA100 strains, recovered from sputum, were susceptible to any GTA concentration, OPA and PA solutions. M. massiliense BRA100 strains presented MIC of 8 percent GTA and were susceptible to OPA and PA. CONCLUSION: M. massiliense BRA100 strain is resistant to high GTA concentrations (up to 7 percent), which proves that this product is non-effective against specific rapidly growing mycobacteria and should be substituted by OPA or PA - based solutions for HLD.

OBJETIVO: Avaliar a concentração mínima inibitória (CMI) de GTA frente a M. massiliense e a susceptibilidade a produtos alternativos para desinfecção de alto nível (DAN). MÉTODOS: Cepas de M. massiliense de origem clínica e de referência foram incluídas no estudo. As culturas ativadas foram submetidas a testes qualitativos com diluições de GTA (de 1,5 por cento a 8 por cento) e com soluções comerciais de ortoftaldeído (OPA) ou ácido peracético (PA), utilizando os tempos de exposição recomendados pela Agência Nacional de Vigilância Sanitária para DAN. RESULTADOS: Todas as cepas de referência e M. massiliense não-BRA100, obtida de escarro, foram susceptíveis às concentrações de GTA, e soluções de OPA e PA. As cepas de M. massiliense BRA100 apresentaram CMI de 8 por cento para GTA e foram susceptíveis a OPA e PA. CONCLUSÃO: M. massiliense BRA100 é resistente a altas concentrações de GTA (até 7 por cento), o que demonstra que esse composto não é eficaz, e deve ser substituído por OPA ou PA nos processos de DAN.

Antimycobacterial neolignans isolated from Aristolochia taliscana

Tuberculosis (TB - Mycobacterium tuberculosis) is an ancient infectious disease that has appeared once again as a serious worldwide health problem and now comprises the second leading cause of death resulting from a single infection. The prevalence of multidrug resistance (MDR) TB is increasing and therapeutic options for treatment are not always accessible; in fact, some patients do not respond to the available drugs. Therefore, there is an urgent need to develop novel anti-TB agents. The aim of the present study was to screen extracts of Aristolochia taliscana, a plant used in traditional Mexican medicine to treat cough and snake bites, for antimycobacterial activity. The hexanic extract of A. taliscana was tested by microdilution alamar blue assay against Mycobacterium strains and bioguided fractionation led to the isolation of the neolignans licarin A, licarin B and eupomatenoid-7, all of which had antimycobacterial activity. Licarin A was the most active compound, with minimum inhibitory concentrations of 3.12-12.5 ìg/mL against the following M. tuberculosis strains: H37Rv, four mono-resistant H37Rv variants and 12 clinical MDR isolates, as well as against five non-tuberculous mycobacteria (NTM) strains. In conclusion, licarin A represents a potentially active anti-TB agent to treat MDR M. tuberculosis and NTM strains.

Infecções por micobactérias de crescimento rápido resistentes a desinfetantes: uma problemática nacional? / Infections by rapidly growing mycobacteria resistant to disinfectants: a national matter?

Rapidly growing mycobacteria (RGM) are opportunistic microorganisms and widely distributed into aqueous environment and soil. Human RGM infections are usually associated with contaminated solutions or medical instruments used during invasive procedures. RGM postsurgical infections have recently emerged in Brazil and have caused national alert, considering the risk factors and epidemiological aspects. This study aimed at analysing the main factors linked to the recent RGM outbreaks, with focus on the national epidemic of Mycobacterium massiliense infections related to the BRA100 strains resistant to 2 percent glutaraldehyde commercial solutions commonly used for preoperative high-level disinfection. Based on previous studies and laboratorial results of assays and colaborations, it has been observed that the cases have been associated with videolaparoscopy for different applications and elective esthetic procedures, such as lipoaspiration and mammary prosthesis implant. Furthermore, outbreaks between 2004 and 2008 and the epidemic in Rio de Janeiro state may be considered particular Brazilian events. Although there are a few epidemiological published studies, some hypotheses based on common aspects related to most national nosocomial occurrences are possible, such as lack of protocols for cleaning and high-level disinfection, use of 2 percent glutaraldehyde as high-level disinfectant for surgical instruments, and dissemination of M. massiliense BRA100 by unknown mechanisms.

Infecção por micobactérias de crescimento rápido após procedimentos videocirúrgicos: a hipótese do glutaraldeído / Rapidly growing mycobacteria infection after videosurgical procedures: the glutaraldehyde hypothesis

Between August 2006 and February 2007, in the state of Rio de Janeiro, Brazil, a massive outbreak of RGM infections after video laparoscopy was mainly associated to the recently described Mycobacterium massiliense species. All confirmed and probable cases reports described the use of high-level disinfection of medical devices by using 2 percent glutaraldehyde (2 percent GA) for 30 min before the surgical procedures. We investigated the susceptibility of the M. massiliense isolates recovered during the outbreak to high-level disinfection after 30 min, 1h, 6h and 10h of exposure to the commercial disinfectants. Reference strains for official mycobactericidal tests such as Mycobacterium abscessus, Mycobacterium bovis, Mycobacterium chelonae, Mycobacterium neoaurum and Mycobacterium smegmatis were included as controls. Although all the reference strains were eliminated in 30 min of exposure to 2 percent GA, we observed the recovery of all M. massiliense clinical isolates even after 10h of exposure. This study suggests that failures in high-level disinfection and the high tolerance of these M. massiliense clinical strains to the 2 percent GA were strongly associated to the magnitude of the outbreak.

In vitro synergic effect of beta-lapachone and isoniazid on the growth of Mycobacterium fortuitum and Mycobacterium smegmatis

Nontuberculous mycobacteria are ubiquitous and saprophytic organisms that have been implicated in a wide spectrum of diseases due to an increasing number of immunocompromised patients. The natural resistance of atypical mycobacteria to classical antituberculous drugs has encouraged research into new chemotherapeutic agents and drug combinations. The aim of this study was to determine the in vitro antimycobacterial activities of ²-lapachone alone and in combination with isoniazid against Mycobacterium fortuitum and Mycobacterium smegmatis via the Time-Kill Curve method. A 2 log10 CFU/mL reduction in the M. smegmatis culture was observed 72 h after adding ²-lapachone at its minimum inhibitory concentration. This drug sterilised the culture in 120 h. For M. fortuitum, a reduction of 1.55 log10 CFU/mL occurred in 24 h, but regrowth was seen in contact with ²-lapachone. Both microorganisms were resistant to isoniazid. Regrowth of M. fortuitum and M. smegmatis was observed at 48 h and 72 h, respectively. In combination, these two drugs had a bactericidal effect and sterilised both cultures in 96 h. These results are valuable because antibiotic-resistant bacteria are a major public health problem.

Sensibilidad a los antimicrobianos de micobacterias de crecimiento rápido mediante el método E-test / Assessment of in vitro susceptibility to antimicrobials of rapidly growing mycobacteria by E-test

Background: Rapidly growing mycobacteria (RGM) are considered opportunistic pathogens. An increasing number of post traumatic or surgical infections are caused by these microorganisms. Aim: To determine the antimicrobial susceptibility of RGM using the E-test method. Material and methods: A total of 54 isolates of RGM was obtained from several clinical samples and selected for this study Strains were identified to the species level by phenotypic and biochemical characteristics, PCR-restriction enzyme analysis of the hsp65 gene (PRA) and sequencing of the 16S rRNA. Susceptibility was investigated by E-test to amikacin, cefoxitin, ciprofioxacin, clarithromycin, imipenem, quinupristin/dalfopristin, linezolid and tigecycline. Results: Twelve different species of RGM were identified: Mycobacterium fortuitum (23 strains), M chelonae (11), M abscessus (10), Msenegalense (2), Malvei (1), Mbrumae (1), Mmageritense (1), mucogenicum (1), M neoaurum (1), Mperegrinum (1), M septicum (1) y M smegmatis (1). All the strains were inhibited by low concentrations of amikacin and tigecycline. Susceptibility to cefoxitin, fluoroquinolones, clarithromycin, imipenem and linezolid was variable. All but two strains were resistant to quinupristin/ dalfopristin. Conclusions: Due to the uneven antimicrobial susceptibility of different species of RGM, an antimicrobial susceptibility test is mandatory for these microorganisms. The E-test method is well suited to determine minimum inhibitory concentrations.

Identificação laboratorial de micobactérias em amostras respiratórias de pacientes HIV-positivos com suspeita de tuberculose / Laboratory identification of mycobacteria in respiratory samples from HIV-positive patients suspected of tuberculosis

Foram analisados retrospectivamente os registros (2000 a 2004) do Laboratório de Microbiologia do Instituto Adolfo Lutz de Santos, SP referentes a pacientes infectados pelo virus da imunodeficiência humana com suspeita de tuberculose pulmonar. Foram encaminhadas 1.321 amostras com finalidade de diagnóstico, correspondendo a 880 casos suspeitos de tuberculose em 693 pacientes. Cento e trinta e quatro baciloscopias foram positivas e em 188 culturas houve crescimento de micobactérias, correspondendo a 161 casos confirmados. Houve identificação de Mycobacterium tuberculosis em 126 (78,3 por cento) e micobactérias não tuberculosas em 39 (24,2 por cento). Em quatro casos, houve concomitância de Mycobacterium tuberculosis e micobactérias não tuberculosas (porém em amostras distintas). O perfil de sensibilidade às drogas antituberculose revelou 18 (14,3 por cento) casos de resistência a pelo menos um medicamento. Estes resultados reforçam a necessidade de submeter à rotina laboratorial completa - baciloscopia, cultura com identificação e testes de sensibilidade às drogas - as amostras respiratórias de pacientes soropositivos para o vírus da imunodeficiência humana com suspeita de tuberculose para direcionamento terapêutico adequado.

The records (2000 to 2004) of the Microbiology Laboratory of the Adolfo Lutz Institute in Santos, Brazil, were retrospectively analyzed regarding patients infected with the human immunodeficiency virus (HIV) and suspected of pulmonary tuberculosis. 1,321 samples for diagnosis purposes were selected, corresponding to 880 suspected tuberculosis cases in 693 patients. There were 134 smear-positive samples and mycobacteria growth occurred in 188 cultures, corresponding to 161 confirmed cases. Mycobacterium tuberculosis was identified in 126 (78.3 percent) and non-tuberculous mycobacteria in 39 (24.2 percent). In four cases, both Mycobacterium tuberculosis and non-tuberculous mycobacteria were simultaneously recovered from different samples. The profile of sensitivity to anti-tuberculosis drugs revealed 18 (14.3 percent) cases of resistance to at least one drug. These results reinforce the need to carrying out the complete laboratorial routine (sputum smear microscopy, culture and susceptibility to antituberculous drugs) for respiratory samples from human immunodeficiency virus-positive patients with suspected tuberculosis in order to direct appropriate therapy.

Mutations in rpoB and katG genes in Mycobacterium isolates from the Southeast of Mexico

The most frequent mutations associated with rifampin and isoniazid resistance in Mycobacterium are the substitutions at codons 531 and 315 in the rpoB and katG genes, respectively. Hence, the aim of this study was to characterize these mutations in Mycobacterium isolates from patients suspected to be infected with drug-resistant (DR) pulmonary tuberculosis (TB) in Veracruz, Mexico. Drug susceptibility testing of 25 clinical isolates revealed that five were susceptible while 20 (80 percent) were DR (15 percent of the annual prevalence for Veracruz). Of the DR isolates, 15 (75 percent) were resistant to rifampin, 17 (85 percent) to isoniazid and 15 (75 percent) were resistant to both drugs (MDR). Sequencing analysis performed in the isolates showed that 14 (93 percent) had mutations in the rpoB gene; seven of these (47 percent) exhibited a mutation at 531 (S[L). Ten (58 percent) of the 20 resistant isolates showed mutations in katG; nine (52 percent) of these 10 exhibited a mutation at 315 (S[T). In conclusion, the DR profile of the isolates suggests a significant number of different DR-TB strains with a low frequency of mutation at codons 531 and 315 in rpoB and katG, respectively. This result leads us to consider different regions of the same genes, as well as other genes for further analysis, which is important if a genetic-based diagnosis of DR-TB is to be developed for this region.

In vitro and in vivo antimycobacterial activity of antiinflammatory drug, diclofenac sodium.

The non-steroidal antiinflammatory drug diclofenac sodium exhibited remarkable inhibitory action against both drug sensitive and drug resistant clinical isolates of Mycobacterium tuberculosis, as well as other mycobacteria. This agent was tested in vitro against 45 different strains of mycobacteria, most of which were inhibited by the drug at 10-25 microg/ml concentration. When tested in vivo, diclofenac, injected at 10 mg/kg body weight of a Swiss strain of white mice, could significantly protect them when challenged with a 50 median lethal dose of M. tuberculosis H37 Rv102. According to Chi-square test, the in vivo data were highly significant (P<0.01).

Resistencia inicial a drogas antituberculosas: Chile, 1997 / Initial resistance to antituberculous drugs in Chile, 1997

Con el objetivo de actualizar la prevalencia de la resistencia inicial (RI) a drogas antituberculosas en Chile, en 1997 se realizó la última determinación nacional de acuerdo a un protocolo estándar recomendado por la Organización Mundial de la Salud (OMS). Se programó estudiar el 50 por ciento de la incidencia de ese año de casos nunca tratados, de tuberculosis pulmonar con baciloscopía positiva. Las pruebas de sensibilidad se realizaron en el Laboratorio de Referencia Nacional de Micobacterias del Instituto de Salud Pública, por el método de las proporciones. Se recibieron 908 cepas, que correspondieron a igual número de enfermos, provenientes de los 26 Servicios de Salud (SS) del país. Luego de excluir 27 cepas por diversas causas, quedaron 881 casos útiles, 732 (83,1 por ciento) nuevos y 149 (16,9 por ciento) con tratamiento previo. La prevalencia global de RI fue de 9,3 por ciento cifra inferior a la de las últimas cuatro determinaciones; su distribución por drogas y asociaciones resultó semejante a la de los estudios previos; la multirresistencia (MR) se encontró en 0,4 por ciento de los casos. La inclusión de 19 pacientes con serología positiva al VIH, no modificó significativamente las cifras. En los enfermos antes tratados se encontró un porcentaje de 18,1 por ciento de resistencia adquirida, semejante a la determinada para ese mismo año en la totalidad de las recaídas y abandonos. La muestra estudiada para RI resultó numérica y cualitativamente representativa de la situación nacional, lográndose así el objetivo de mantener la vigilancia actualizada de su prevalencia en todo el país

Plants from Puerto Rico with anti-Mycobacterium tuberculosis properties

OBJECTIVE: This study assesses the antitubercular potential of natural products obtained from plants reputed to have medicinal properties and collected from the tropical flora of Puerto Rico. BACKGROUND: The increase in persons infected with Mycobacterium tuberculosis (MTB) the world over and the development of resistance to antibiotics by this microbe and other infectious bacteria has created the need for new drugs to replace those which have lost effectiveness. METHOD: In Phase I of this study, ethanolic leaf extracts of fifty local plants were submitted to preliminary screening to assess their in vitro Mycobacterium smegmatis inhibitory activity using the Bauer-Kirby disk diffusion method. In Phase II, the definitive screening of the six most promising extracts which inhibited M. smegmatis were assayed for their MTB inhibitory activity using the BACTEC 460 susceptibility test method. The brine shrimp bioassay was used as a toxicity bioassay and the mice inoculation test was used to determine mice tolerance to the effect of the daily intraperitoneal inoculations of the plant extracts. RESULTS: MTB showed varying degrees of susceptibility to each plant extract. This effect was dependent upon the plant species, dose and time of exposure. Evidence is provided suggesting that: (1) Six crude plant extracts (12 per cent) tested possessed inhibitory capacity at the amount of 500 micrograms per disc; (2) Mammea americana extract yielded the strongest inhibitory effect at 50 micrograms per disc, followed by Marchantia polymorpha, Mangifera indica, Callistemon citrinus, Syzygium jambos and Momordica charantia; (3) the bactericidal inhibitory pattern of MTB growth, exposed to Mammea americana extract, was comparable to streptomycin; and (4) the transitory reduction pattern of MTB growth, produced by Callistemon citrinus, Marchantia polymorpha extracts at 100 micrograms and 250 micrograms, was similar to that of bacteriostatic agents. CONCLUSION: Of 50 plants screened six extracts tested for their anti-MTB activity yielded positive results with varying degrees of inhibition. Mammea americana showed the greatest inhibitory activity suggesting that certain plant species yield valuable anti-Mycobacterium tuberculosis substances. The procedures employed in this study, including the BACTEC 460 modified method, are useful for in vitro screening of plant extracts with potential antitubercular activity.