String test: A new tool for tuberculosis diagnosis and drug-resistance detection in children.

Background: There is a critical need to improve the diagnostic accuracy of tuberculosis (TB) in children. Several techniques have been developed to improve the quality of sputum samples; however, these procedures are very unpleasant and invasive and require hospitalization and trained personnel. This study aims to explore the potential use of a new and noninvasive tool, "string test," for TB diagnosis in children and in adults not able to render sputum samples and at risk of developing multidrug-resistant TB (MDR-TB). Methods: Children with clinical suspicion of TB attending the pediatric consultation at the Cetrangolo or Cordero Hospitals and adults suspected of MDR-TB and unable to produce sputum attending the Infectious Disease Unit of Cetrangolo Hospital were included in this study. Subjects and Methods: The "string test" is a string that is swallowed by the patients and exposed to gastrointestinal secretions that were late analyzed for TB diagnosis and drug-resistance detection by GenoType MTBDRplus. MedCalc software was used to perform statistical analysis. Results: This technique could be applied on 62.1% of selected children. About 11 (30.6%) children were diagnosed as TB cases, 8 (22.2%) from gastric aspirate and using the "string test." Six out of 19 adults were also diagnosed. Genotype directly on the string specimen detected two MDR-TB in adults and two isoniazid-resistant cases before obtaining the isolate. Conclusion: This test was safe, cheap, and easily implemented without requiring hospitalization. This research could represent a significant step forward to diagnose and rapidly detect drug-resistant TB in children.

Actualización del tratamiento de la Hepatitis por virus C en pacientes con insuficiencia renal crónica en hemodiálisis / Update of Hepatitis C therapy in patients with chronic kidney disease on hemodialysis

El Virus de la Hepatitis C (VHC), agente etiológico de la hepatitis ocasionada por el VHC, fué descubierto hace 25 años. En la mayoría de los casos evoluciona hacia la cronicidad como hepatitis crónica a virus C (55-85%) y cursa con manifestaciones clínicas de sus complicaciones hepáticas: cirrosis, hepatocarcinoma y extrahépaticas. Este virus es endémico en las unidades de Hemodiálisis (HD), con frecuentes brotes que afectan a múltiples pacientes y a pesar que ha disminuido su prevalencia aún hoy triplica la de la población general y continúa siendo un problema en especial para aquellos pacientes con serología anti-VHC positiva que reciben un trasplante renal. En la década pasada el pilar del tratamiento para VHC era Interferón Pegilado y Ribavirina, muy complejo por: la toxicidad de algunas drogas (ej. Ribavirina), la alta prevalencia de eventos adversos y la baja tasa de respuesta virológica y clínica. La reciente aparición de drogas de acción directa (DAA) que pueden curar más del 95% de los casos de infección por el VHC, ha modificado sustancialmente el pronóstico de estos pacientes con reducción del riesgo de muerte por cáncer de hígado y cirrosis, pero el acceso al diagnóstico y el tratamiento es limitado por los elevados costos. Este trabajo tiene como objetivo introducir al especialista en nefrología a cargo de los pacientes en HD en el nuevo escenario que promueve la aparición de diversas DAA para el tratamiento del VHC y plantear las controversias que deben dilucidarse sobre conductas en los pacientes tratados

Hepatitis C virus (HCV), causative agent of hepatitis C, was discovered 25 years ago. Most patients develop chronic HCV infection (55-85 %), which manifests with hepatic complications (cirrhosis, hepatocellular carcinoma) and extrahepatic ones. This virus is endemic in hemodialysis (HD) units, many patients being affected by its frequent outbreaks; although its prevalence has diminished, it is still three times higher than the one in the general population, and it continues to be a problem, especially for kidney transplantation patients with positive anti-HCV tests. In the last decade, the most important HCV infection treatment drugs were peginterferon and ribavirin; however, treatment was very complex due to some drugs toxicity (e.g. ribavirin), frequent adverse events and low virological and clinical response. The appearance of direct-acting antivirals (DAA) that cure more than 95 % of HCV infection cases has changed these patients' prognoses considerably and reduced the risk of death by liver cancer and cirrhosis. Access to diagnosis and treatment, on the other hand, is limited due to high costs. The aim of this study is to show nephrologists treating patients on HD the scenario brought about by the introduction of DAAs for HCV infection treatment and to discuss the dilemmas over the patients' treatment which needs to be solved.

Relevancia clínica, diversidad y variabilidad genética de distintas especies del género Mycobacterium / Clinical Relevance, Diversity and Genetic Variability of Different Species within the Genus Mycobacterium

Introducción: El término micobacterias no tuberculosas (MNT) incluye distintas especies ambientales capaces de enfermar humanosy/o animales incluso mediante una probable transmisión zoonótica Objetivos. Determinar: la importancia clínica de varias especies del género Mycobacterium y la diversidad genética del Complejo M. avium (MAC), la sensibilidad bacteriana in vitro yel éxito del tratamiento especifico. Materiales y Métodos: Recolección de datos clínicos, epidemiológicos y aislamientos en el periodo 2009-2016; identificación molecular de los aislamientos; determinación de la sensibilidad bacteriana in vitro y de la diversidad genética del MAC; evaluación del tratamiento. Resultados: Fueron diagnosticados 225 casos de micobacteriosis, con prevalencia estable ≈ 6% por año, y 22 especies recuperadas: 4 de rápido desarrollo aisladas de 66 pacientes y 18 de lento desarrollo. MAC fue aislado en 95 casos, 40 M. avium hominissuis, 51 M. intracellulare, 3 M. chimaera, 1 M. colombiense. Se observó mayor probabilidad de enfermar por M. intracellulare en pacientes tratados previamente por tuberculosis (TB). Los pacientes HIV+ tuvieron riesgo incrementado de enfermedad causada por M. avium hominissuis. Los aminoglucósidos, fluoroquinolonas y macrólidos fueron las drogas más activas frente a la mayoría de las MNT. Aproximadamente la mitad de los casos curaron. Conclusiones: M. intracellulare, M. aviumhominissuis con una gran variabilidad genética, y M. abscessus fueron los patógenos más frecuentemente hallados. Un hallazgo importante fue el de casos de enfermedad mixta TB+MNT. Estos pacientes requirieron una terapia con agregado de drogas de segunda línea al esquema terapéutico para TB habiendo curado la mayoría de ellos.

Introduction: The term non-tuberculous mycobacteria (NTM) includes different ambient species capable of sickening humans and/or animals, even by means of a potential zoonotic transmission. Objectives: To determine: The clinical importance of several species within the genus Mycobacterium and the genetic diversity of the M. avium complex (MAC), the in vitro bacterial sensitivity and the success of the specific treatment. Materials and Methods: Collection of clinical and epidemiologic data and information about isolates of the 2009-2016 period; molecular identification of the isolates; determination of the in vitro bacterial sensitivity and genetic diversity of the MAC; treatment evaluation. Results: 225 mycobacteriosis cases were diagnosed, with a stable prevalence of ≈6% per year and 22 recovered species: 4 rapidly growing species isolated from 66 patients and 18 slowly growing species. The MAC was isolated in 95 cases, M. avium hominissuis - 40 cases, M. intracellulare - 51 cases, M. chimaera - 3 cases and M. colombiense - 1 case. We observed a greater probability of getting sick from M. intracellulare in patients previously treated for tuberculosis (TB). HIV-positive patients had a greater risk of falling ill from M. avium hominissuis. Aminoglycosides, fluoroquinolones and macrolides were the most active drugs against most NTM. Approximately half of the cases healed. Conclusions: M. intracellulare, M. aviumhominissuis with great genetic variability and M. abscessus were the most commonly found pathogens. The cases of TB+NTM mixed disease were an important finding. For treating these patients, it was necessary to add second line drugs to the therapeutic regimen for TB; and most of them healed.

Clinical Relevance, Diversity and Genetic Variability of Different Species within the Genus Mycobacterium

Introduction: The term non-tuberculous mycobacteria (NTM) includes different ambient species capable of sickening humans and/or animals, even by means of a potential zoonotic transmission. Objectives: To determine: The clinical importance of several species within the genus Mycobacterium and the genetic diversity of the M. avium complex (MAC), the in vitro bacterial sensitivity and the success of the specific treatment. Materials and Methods: Collection of clinical and epidemiologic data and information about isolates of the 2009-2016 period; molecular identification of the isolates; determination of the in vitro bacterial sensitivity and genetic diversity of the MAC; treatment evaluation. Results: 225 mycobacteriosis cases were diagnosed, with a stable prevalence of ≈6% per year and 22 recovered species: 4 rapidly growing species isolated from 66 patients and 18 slowly growing species. The MAC was isolated in 95 cases, M. avium hominissuis - 40 cases, M. intracellulare - 51 cases, M. chimaera - 3 cases and M. colombiense - 1 case. We observed a greater probability of getting sick from M. intracellulare in patients previously treated for tuberculosis (TB). HIV-positive patients had a greater risk of falling ill from M. avium hominissuis. Aminoglycosides, fluoroquinolones and macrolides were the most active drugs against most NTM. Approximately half of the cases healed. Conclusions: M. intracellulare, M. aviumhominissuis with great genetic variability and M. abscessus were the most commonly found pathogens. The cases of TB+NTM mixed disease were an important finding. For treating these patients, it was necessary to add second line drugs to the therapeutic regimen for TB; and most of them healed