High-resolution melting analysis for molecular detection of multidrug resistance tuberculosis in Peruvian isolates.

BACKGROUND: The emergence of multidrug-resistant strains is a major health problem especially for countries with high TB incidence such as Peru. In this study, we evaluated High Resolution Melting (HRM) assay in Peruvian isolates for the detection of mutations within rpoB, katG genes and promoter region inhA to determine isoniazid and rifampicin resistance in Mycobacterium tuberculosis (Mtb). METHODS: DNA samples extracted from a total of 167 clinical isolates of Mtb, 89 drug-sensitive and 78 multidrug-resistant, were blindly analyzed by HRM analysis and verified by DNA sequencing. RESULTS: The HRM analysis generated patterns that were specific to distinguish between sensitive and resistance isolates. The sensitivity and specificity of the HRM assays in comparison with drug susceptibility testing (DST) for detection of rifampicin resistance were 98.7 % and 97.5 %, and for isoniazid resistance were 98.7 % and 100 %. CONCLUSION: This study suggests that HRM Analysis could help with rapid diagnosis of MDR-TB cases in Peru.

Transmission of Multidrug-Resistant and Drug-Susceptible Tuberculosis within Households: A Prospective Cohort Study.

BACKGROUND: The "fitness" of an infectious pathogen is defined as the ability of the pathogen to survive, reproduce, be transmitted, and cause disease. The fitness of multidrug-resistant tuberculosis (MDRTB) relative to drug-susceptible tuberculosis is cited as one of the most important determinants of MDRTB spread and epidemic size. To estimate the relative fitness of drug-resistant tuberculosis cases, we compared the incidence of tuberculosis disease among the household contacts of MDRTB index patients to that among the contacts of drug-susceptible index patients. METHODS AND FINDINGS: This 3-y (2010-2013) prospective cohort household follow-up study in South Lima and Callao, Peru, measured the incidence of tuberculosis disease among 1,055 household contacts of 213 MDRTB index cases and 2,362 household contacts of 487 drug-susceptible index cases. A total of 35/1,055 (3.3%) household contacts of 213 MDRTB index cases developed tuberculosis disease, while 114/2,362 (4.8%) household contacts of 487 drug-susceptible index patients developed tuberculosis disease. The total follow-up time for drug-susceptible tuberculosis contacts was 2,620 person-years, while the total follow-up time for MDRTB contacts was 1,425 person-years. Using multivariate Cox regression to adjust for confounding variables including contact HIV status, contact age, socio-economic status, and index case sputum smear grade, the hazard ratio for tuberculosis disease among MDRTB household contacts was found to be half that for drug-susceptible contacts (hazard ratio 0.56, 95% CI 0.34-0.90, p = 0.017). The inference of transmission in this study was limited by the lack of genotyping data for household contacts. Capturing incident disease only among household contacts may also limit the extrapolation of these findings to the community setting. CONCLUSIONS: The low relative fitness of MDRTB estimated by this study improves the chances of controlling drug-resistant tuberculosis. However, fitter multidrug-resistant strains that emerge over time may make this increasingly difficult.

Validation of the Mexican Spanish version of the EORTC C30 and STO22 questionnaires for the evaluation of health-related quality of life in patients with gastric cancer.

Health-related quality of life (HRQL) is a fundamental outcome in surgical oncology and culturally valid tools are essential for this purpose. Our aim was to validate the Mexican-Spanish versions of the European Organization for Research and Treatment of Cancer (EORTC) Quality-of-Life Questionnaire QLQ-C30 and the QLQ-STO22 disease-specific questionnaire module in Mexican patients with gastric cancer (GC). The translation procedure followed EORTC guidelines. Both instruments were completed by patients with GC and analyses were performed within three clinically distinct groups: (1) patients undergoing palliative treatment, (2) patients undergoing treatment with curative intent, and (3) GC survivors. Tests for reliability and validity were performed. One hundred and fifty patients (mean age 54.2 years) completed both questionnaires. Sixty-seven, 55, and 28 patients were allocated to groups 1, 2, and 3, respectively. Compliance rates were high, and questionnaires were well-accepted. Survivors of treatment for GC reported better functional HRQL scores and lower symptom scores than patients in group 2 who were currently undergoing treatment. Patients selected for potentially curative treatment had better HRQL than group 1 (palliative treatments). Scales in the QLQ-C30 and QLQ-STO22 distinguished between other clinically distinct groups of patients. Cronbach's alpha coefficients of 14 scales of both questionnaires were >0.7. Multitrait scaling analysis demonstrated good convergent and discriminant validity. Test-retest scores were consistent. We conclude that the Mexican-Spanish versions of EORTC QLQ-C30 and QLQ-C22 questionnaires are reliable and valid for HRQL measurement in patients with GC and are therefore recommended for use in clinical trials of Mexican community.

The Association between Mycobacterium Tuberculosis Genotype and Drug Resistance in Peru.

BACKGROUND: The comparison of Mycobacterium tuberculosis bacterial genotypes with phenotypic, demographic, geospatial and clinical data improves our understanding of how strain lineage influences the development of drug-resistance and the spread of tuberculosis. METHODS: To investigate the association of Mycobacterium tuberculosis bacterial genotype with drug-resistance. Drug susceptibility testing together with genotyping using both 15-loci MIRU-typing and spoligotyping, was performed on 2,139 culture positive isolates, each from a different patient in Lima, Peru. Demographic, geospatial and socio-economic data were collected using questionnaires, global positioning equipment and the latest national census. RESULTS: The Latin American Mediterranean (LAM) clade (OR 2.4, p<0.001) was significantly associated with drug-resistance and alone accounted for more than half of all drug resistance in the region. Previously treated patients, prisoners and genetically clustered cases were also significantly associated with drug-resistance (OR's 2.5, 2.4 and 1.8, p<0.001, p<0.05, p<0.001 respectively). CONCLUSIONS: Tuberculosis disease caused by the LAM clade was more likely to be drug resistant independent of important clinical, genetic and socio-economic confounding factors. Explanations for this include; the preferential co-evolution of LAM strains in a Latin American population, a LAM strain bacterial genetic background that favors drug-resistance or the "founder effect" from pre-existing LAM strains disproportionately exposed to drugs.

A field evaluation of the Hardy TB MODS Kit™ for the rapid phenotypic diagnosis of tuberculosis and multi-drug resistant tuberculosis.

BACKGROUND: Even though the WHO-endorsed, non-commercial MODS assay offers rapid, reliable TB liquid culture and phenotypic drug susceptibility testing (DST) at lower cost than any other diagnostic, uptake has been patchy. In part this reflects misperceptions about in-house assay quality assurance, but user convenience of one-stop procurement is also important. A commercial MODS kit was developed by Hardy Diagnostics (Santa Maria, CA, USA) with PATH (Seattle, WA, USA) to facilitate procurement, simplify procedures through readymade media, and enhance safety with a sealing silicone plate lid. Here we report the results from a large-scale field evaluation of the MODS kit in a government service laboratory. METHODS & FINDINGS: 2446 sputum samples were cultured in parallel in Lowenstein-Jensen (LJ), conventional MODS and in the MODS kit. MODS kit DST was compared with conventional MODS (direct) DST and proportion method (indirect) DST. 778 samples (31.8%) were Mycobacterium tuberculosis culture-positive. Compared to conventional MODS the sensitivity, specificity, positive, and negative predictive values (95% confidence intervals) of the MODS Kit were 99.3% (98.3-99.8%), 98.3% (97.5-98.8%), 95.8% (94.0-97.1%), and 99.7% (99.3-99.9%). Median (interquartile ranges) time to culture-positivity (and rifampicin and isoniazid DST) was 10 (9-13) days for conventional MODS and 8.5 (7-11) for MODS Kit (p<0.01). Direct rifampicin and isoniazid DST in MODS kit was almost universally concordant with conventional MODS (97.9% agreement, 665/679 evaluable samples) and reference indirect DST (97.9% agreement, 687/702 evaluable samples). CONCLUSIONS: MODS kit delivers performance indistinguishable from conventional MODS and offers a convenient, affordable alternative with enhanced safety from the sealing silicone lid. The availability in the marketplace of this platform, which conforms to European standards (CE-marked), readily repurposed for second-line DST in the near future, provides a fresh opportunity for improving equity of access to TB diagnosis and first and second-line DST in settings where the need is greatest.

Cryptococcus neoformans en heces de palomas (Columba livia) en Lima Metropolitana / Cryptococcus neoformans in the stools of dove (Columba livia) in metropolitan Lima

Objetivos: Investigar la presencia del hongo levaduriforme Cryptococcus neoformans en heces de palomas domésticas (Columba livia). Material y métodos: Estudio descriptivo transversal realizado en la ciudad de Lima- Perú. Se recolectaron 300 muestras de heces encontradas en los suelos de parques y hospitales. Además se tomó 30 muestras de las cloacas de algunas palomas capturadas. Resultados: Se aisló el hongo en 47 muestras de las que 7 correspondieron al Cryptococcus neoformans var. neoformans pero no se aisló el hongo en cloaca. Las 7 cepas aisladas tuvieron 100% de sensibilidad frente a Anfotericin B, Nistatina y Clotrimazol; además presentaron 100% de resistencia a Fluconazol e Itraconazol y 57% de resistencia a Ketoconazol. Conclusiones: Cryptococcus neoformans se encuentra presente en heces de palomas en Lima Metropolitana. (AU)

Objectives: To evaluate the presence of Cryptococcus neoformans in the stools of domestic dove (Columba livia). Methods: Cross-sectional study carried-out in the city of Lima-Peru. 300 stool samples found in the soil of parks and hospital were collected. In addition, 30 sewage samples were also processed. Results: the fungus was isolated in 47 samples, Cryptococcus neoformans var neoformans was isolated in 7 of these samples, none was isolated from sewage samples. The seven strains showed 100% susceptibility to amphotericin B, nystatin and clotrimazol, but showed 100% resistance to fluconazole and itraconazole and 57% resistance to ketoconazole. Conclusions: Cryptococcus neoformansis found in the stools of domestic dove in metropolitan Lima. (AU)

[Cost analysis of rapid methods for diagnosis of multidrug resistant tuberculosis in different epidemiologic groups in Perú]. / Análisis de costos de los métodos rápidos para diagnóstico de tuberculosis multidrogorresistente en diferentes grupos epidemiológicos del Perú.

OBJECTIVES: To evaluate the costs of three methods for the diagnosis of drug susceptibility in tuberculosis, and to compare the cost per case of Multidrug-resistant tuberculosis (MDR TB) diagnosed with these (MODS, GRIESS and Genotype MTBDR plus®) in 4 epidemiologic groups in Peru. MATERIALS AND METHODS: In the basis of programmatic figures, we divided the population in 4 groups: new cases from Lima/Callao, new cases from other provinces, previously treated patients from Lima/Callao and previously treated from other provinces. We calculated the costs of each test with the standard methodology of the Ministry of Health, from the perspective of the health system. Finally, we calculated the cost per patient diagnosed with MDR TB for each epidemiologic group. RESULTS: The estimated costs per test for MODS, GRIESS, and Genotype MTBDR plus® were 14.83. 15.51 and 176.41 nuevos soles respectively (the local currency, 1 nuevos sol=0.36 US dollars for August, 2011). The cost per patient diagnosed with GRIESS and MODS was lower than 200 nuevos soles in 3 out of the 4 groups. The costs per diagnosed MDR TB were higher than 2,000 nuevos soles with Genotype MTBDR plus® in the two groups of new patients, and lower than 1,000 nuevos soles in the group of previously treated patients. CONCLUSIONS: In high-prevalence groups, like the previously treated patients, the costs per diagnosis of MDR TB with the 3 evaluated tests were low, nevertheless, the costs with the molecular test in the low- prevalence groups were high. The use of the molecular tests must be optimized in high prevalence areas.

Propiedades psicométricas de la Escala Hospitalaria de Ansiedad y Depresión (HADS) en una población de pacientes oncológicos mexicanos / Psychometric properties of the Hospital Anxiety and Depression Scale (HADS) in a Mexican population of cancer patients

ANTECEDENTES: La sintomatología ansiosa y depresiva es parte de los principales problemas de salud mental en pacientes oncológicos, lo cual afecta la calidad de vida y la adhesión al tratamiento, además de que se asocia con mayor número de síntomas y estancia hospitalaria. Mediante instrumentos de tamizaje válidos y confiables, como la Escala hospitalaria de ansiedad y depresión (HADS), ha sido posible detectar posibles casos en pacientes hospitalarios. Sin embargo, hasta ahora no se habían caracterizado las propiedades psicométricas en pacientes oncológicos en población mexicana.OBJETIVO: Determinar las propiedades psicométricas de la HADS en una muestra de pacientes oncológicos.MÉTODO: Participaron 400 pacientes del Instituto Nacional de Cancerología, de los cuales 226 eran mujeres (56.5%) y 174 eran hombres (43.6%); la edad promedio fue de 47.4 ± 14.1 años. Los participantes contestaron, además de la HADS, los siguientes inventarios: depresión de Beck, ansiedad de Beck, termómetro de distrés.RESULTADOS: Un análisis factorial ajustado a dos factores presentó un instrumento con 12 reactivos, similar a la versión original. La consistencia interna de la escala global mostró un índice satisfactorio (a=0.86). Los alfas de Cronbach de cada subescala tuvieron un valor de .79 y .80 que explicaron el 48.04% de la varianza. La validez, por medio de correlación con las medidas concurrentes, mostró resultados significativos (r de Pearson de .51 a .71, p<0.05).DISCUSIÓN Y CONCLUSIÓN: La HADS en pacientes con cáncer en población mexicana presentó adecuadas características psicométricas. La relevancia de los resultados obtenidos radica en que se trata de una población que puede llegar a requerir atención oportuna en salud mental en etapas tempranas de su tratamiento. La detección de sintomatología ansiosa y depresiva por medio de la HADS deriva en beneficios para la población oncológica y en estrategias funcionales de atención adecuada y costo-efectivas.

BACKGROUND: Symptoms of anxiety and depression are among the major mental health problems in cancer patients. These symptoms affect the quality of life and treatment adherence, and are associated with other symptoms and longer hospital stays. Valid and reliable screening instruments such as the Hospital Anxiety and Depression Scale (HADS), have made possible the detection of possible cases of depression and anxiety in medically ill patients. However, the psychometric properties of this instrument have not been documented in different types of cancer diagnoses in the Mexican population.OBJECTIVE: To determine the psychometric properties of the HADS in a sample of patients with cancer from the Mexican population.METHOD: Four hundred patients from the National Cancer Institute participated, of which 226 were women (56.5%) and 174 men (43.6%), with a mean age of 47.4 ±14.1 years. Participants completed concurrently the HADS as well as the following inventories: 1. Beck Depression, 2. Beck Anxiety and 3. Distress Thermometer.RESULTS: A factor analysis adjusted to two factors explained 48.04% of the variance, with 12 items loading on these two factors in a way similar to the original version. The internal consistency of the overall scale was satisfactory (α=0.86). Cronbach's alphas for each subscale were .79 and .80. The concurrent validity assessed by way of correlations with concurrent measures showed significant associations (Pearson r=51-71, p<0.05).DISCUSSION AND CONCLUSION: The HADS has adequate construct validity, internal consistency and concurrent validity for its use in cancer patients from the Mexican population. The relevance of these results is a cost effective tool to provide timely mental health care early in oncological treatment for those in need. Detecting anxiety and depression symptoms through the HADS may benefit cancer patients by ensuring appropriate care that may increase their quality of life and treatment adherence, and reduce their hospital stays.

Análisis de costos de los métodos rápidos para diagnóstico de Tuberculosis multidrogorresistente en diferentes grupos epidemiológicos del Perú / Cost analysis of rapid methods for diagnosis of multidrug resistant Tuberculosis in different epidemiologic groups in Perú

Objetivos. Evaluar los costos de tres métodos diagnósticos para susceptibilidad a drogas antituberculosas y comparar el costo por caso de tuberculosis multidrogorresistente (TB MDR) diagnosticado con estos (MODS; GRIESS y Genotype MTBDR plus ® en cuatro grupos epidemiológicos en el Perú. Materiales y métodos. En base a cifras programáticas, se dividió a la población en cuatro grupos: pacientes nuevos de Lima/Callao; nuevos de otras provincias; los antes tratados de Lima/Callao y de otras provincias. Se calcularon los costos de cada prueba en base a la metodología estándar utilizada por el Ministerio de Salud, desde la perspectiva de los servicios de salud. Basado en ello, se calculó el costo por paciente TB MDR diagnosticado para cada grupo epidemiológico. Resultados. Los costos estimados por prueba para MODS, GRIESS, y Genotype MTBDR plus ® fueron de 14,83; 15,51 y 176,41 nuevos soles, respectivamente. El costo por paciente TB MDR diagnosticado con GRIESS y MODS fue menor a los 200 nuevos soles en tres de los cuatro grupos. El costo por TB MDR diagnosticado fue de más de 2000 nuevos soles con el Genotype MTBDR plus ® en los dos grupos de pacientes nuevos y, menores a 1000 nuevos soles en los grupos de pacientes antes tratados. Conclusiones. En grupos de alta prevalencia, como son los pacientes antes tratados, los costos por caso diagnosticado de TB MDR con las tres pruebas evaluadas fueron bajos, sin embargo, con la prueba molecular en los grupos de baja prevalencia, fueron elevados. El uso de las pruebas moleculares debe optimizarse en grupos de altas prevalencias.

Objectives.To evaluate the costs of three methods for the diagnosis of drug susceptibility in tuberculosis, and to compare the cost per case of Multidrug-resistant tuberculosis (MDR TB) diagnosed with these (MODS, GRIESS and Genotype MTBDR plus ® in 4 epidemiologic groups in Peru. Materials and methods.In the basis of programmatic figures, we divided the population in 4 groups: new cases from Lima/Callao, new cases from other provinces, previously treated patients from Lima/Callao and previously treated from other provinces. We calculated the costs of each test with the standard methodology of the Ministry of Health, from the perspective of the health system. Finally, we calculated the cost per patient diagnosed with MDR TB for each epidemiologic group. Results. The estimated costs per test for MODS, GRIESS, and Genotype MTBDR plus® were 14.83. 15.51 and 176.41 nuevos soles respectively (the local currency, 1 nuevos sol=0.36 US dollars for August, 2011). The cost per patient diagnosed with GRIESS and MODS was lower than 200 nuevos soles in 3 out of the 4 groups. The costs per diagnosed MDR TB were higher than 2,000 nuevos soles with Genotype MTBDR plus ® in the two groups of new patients, and lower than 1,000 nuevos soles in the group of previously treated patients. Conclusions. In high-prevalence groups, like the previously treated patients, the costs per diagnosis of MDR TB with the 3 evaluated tests were low, nevertheless, the costs with the molecular test in the low- prevalence groups were high. The use of the molecular tests must be optimized in high prevalence areas.

Volumen de trabajo del entrenado de la Maestría FETP: Clase 2000 - 2002

Contiene: 1- Informe de estudios de epidemias o conglomerados, 2- Evaluación de un sistema de vigilancia, 3- Estudio de investigación a mediano - largo plazo.

Importancia del conocimiento de la flora bacteriana normal en el humano / Significance of the knowledge of the normal bacterial flora in humans

Se efectua una revisión bibliográfica sobre la importancia de la flora bacteriana normal en el humano, haciendo énfasis en la relación y equilibrio de la triada germen-hombre-medio ambiente, su conocimiento y localización en las diferentes áreas corporales, sus interaciones y los variados roles etiopatológicos, producto de la simbiosis con el hombre. El interés de este artículose fundamenta en la necesidad constante, presente y futura que tienen los profesionales del área de la salud de realizar una adecuada interpretación de los hallazgos bacteriológicos en pacientes con enfermedades infecciosas agudas o crónicas, las cuales constituyen una de las principales afecciones que aquejan a nuestra especie

Hemocultivos en un Hospital Universitario / Blood cultures in an Universitary Hospital

En el Hospital Universitario de Caracas se procesa un promedio de siete hemocultivos diarios, por lo cual se revisaron los resultados bacteriológicos de 5.423 muestras de sangre, enviadas a la Sección de Bacteriología, para estudios microbiológicos, en el lapso de dos años. En el 27% de ese universo crecieron bacterias, consideradas patógenas para pacientes con bactiemias. Se analizan los diagnósticos presuntivos que acompañaron la solicitud de esos hemocultivos y el orden de frecuencia de los principales microorganismos aislados. Se concluye recomendando la necesidad de la adecuada comunicación entre el clínico y el bacteriológico, para reforzar los vínculos del trabajo en equipo institucional; contribuir así a aliviar el sufrimiento humano del paciente infectado más eficazmente, como también el ahorro efectivo en tiempo y material utilizado en los estudios de orden microbiológico

Escherichia coli: aislamientos microbiológicos en un Hospital Universitario / Escherichia Coli: isolation microbiologic in the Hospital Universitario

Durante un año se efectuó un estudio de vigilancia microbiológica de los aislamientos de E.coli identificados en la Sección de Bacteriología del Hospital Universitario de Caracas, por ser esta bacteria la más frecuentemente aislada en la institución y la segunda en importancia en la etiología de las infecciones nosocomiales registradas. Se identifican 559 cepas de E.coli, procedentes de 557 hospitalizados, de las cuales el 31% se aisló de muestras de orina; el 24% de secreciones de tejidos blandos superficiales; el 20%, de secreciones de heridas quirúrgicas; y el 12%, del tracto digestivo. La mayoría de las muestras para aislamientos bacteriológicos fué enviada por los servicios de Cirugía, Medicina, Neomatología y Urología. El porcentaje más alto de sensibilidad a los antimicrobianos correspondió a cefotaxime, con 98%, seguido por amikamicina, con 95%, tobramicina, con 91%. El de más baja sensibilidad fué ampicilina, con 50%. El trabajo es una adaptación de la vigilancia microbiológica a los aislamientos rutinarios de E.coli en una sección de Bacteriología; en los actuales momentos de crisis económica que vive el país, se hace necesaria la utilización racional de todos los recursos humanos y materiales de nuestro Sistema de Salud