Host characteristics predict outcome among adult patients admitted by severe acute respiratory infection / Características del huésped predicen el desenlace en adultos hospitalizados por infección respiratoria aguda grave

Background: Except for influenza pandemics, different observational studies have failed to demonstrate differences in mortality between various etiologies in adult patients hospitalized for respiratory infections. Aim: To compare clinical and mortality differences between different viral pathogens associated with severe acute respiratory infections (SARI) in hospitalized adults. Material and Methods: One-year prospective study in a sentinel center. We included 132 patients with SARI hospitalized for any of the nine viruses under study by PCR. Clinical variables were compared, excluding cases of coinfection. Results: A viral coinfection was identified in 12% and influenza infection in 56% of cases. Eighty percent of patients were aged ≥ 65 years, with a high frequency of comorbidities, 27% were bedridden. Twenty four percent were admitted to critical care units, 20% required ventilatory assistance and 16% died. Cases occurred throughout the year, with an expected seasonal peak between autumn and spring and a predominance of infections not associated with influenza during summer months. In the multivariate analysis, only being bedridden was significantly associated with mortality at discharge (Odds ratio 23.46; 95% confidence intervals 3.33-165.12, p < 0.01), without association with age, comorbidity, viral pathogen involved, laboratory parameters, clinical presentation or CURB65 score. No major clinical dissimilarities were found between different viral pathogens. Conclusions: In our series of patients, mostly elderly, only bedridden status was significantly associated with mortality at discharge in patients hospitalized for SARI. Viral pathogens were not relevant.

Los factores del huésped son más importantes que el tipo viral para predecir el desenlace en pacientes hospitalizados por infecciones respiratoria aguda grave. Exceptuando las pandemias de influenza, diferentes estudios observacionales no han logrado demostrar diferencias en mortalidad entre diferentes patógenos en pacientes adultos hospitalizados por infecciones respiratorias. Objetivo: Comparar diferencias clínicas y en mortalidad entre diferentes patógenos virales asociados a infección respiratoria aguda grave (IRAG) en adultos hospitalizados. Método: Estudio prospectivo durante un año en un centro centinela. Se incluyeron casos de IRAG hospitalizados por alguno de los 9 virus bajo estudio por RCP. Se compararon variables clínicas y desenlace. Resultados: Ingresaron 132 pacientes con IRAG. Se identificó coinfección viral en 12,1% e infección por influenza en 56,1%. La mayor parte era de la tercera edad (80,3%) con una alta frecuencia de comorbilidad y 27,3% estaba postrado. Veintitres coma cinco por ciento ingresó a unidad de cuidados críticos, 19,7% requirió asistencia ventilatoria y 15,9% fallecieron. Los casos ocurrieron todo el año, con un aumento estacional esperado entre otoño y primavera y predominio de infecciones no asociadas a influenza en verano. En el análisis multivariado, sólo la postración se asoció significativamente a mortalidad al egreso (ORa 23,46 IC95 3,33-165,12, p = 0,002), sin asociación con la edad, comorbilidad, patógeno viral involucrado, parámetros de laboratorio, presentación clínica o puntuación CURB65. No se encontraron discordancias clínicas mayores entre diferentes agentes virales. Conclusiones: En nuestra serie de pacientes, mayoritariamente de la tercera edad, sólo la postración se asoció significativamente a mortalidad al egreso en pacientes hospitalizados por IRAG. El patógeno viral no resultó ser relevante.

Glomerulonefritis aguda con requerimiento de diálisis asociada a influenza A H1N1pdm09: comunicación de dos casos / Acute glomerulonephritis with hemodialysis requirement secondary to influenza A H1N1pdm09 infection: report of two cases

Acute renal failure (ARF) requiring hemodialysis is not common among patients affected by influenza. We report two unvaccinated adult patients with smoking habit, which were admitted with severe influenza A H1N1pdm09 that evolved with shock and required mechanical ventilation. Both patients developed progressive renal failure with oliguria/anuria, associated with urinary of inflammatory sediment with proteinuria, microhematuria and in one case also with hypocomplementemia, suggesting acute glomerulonephritis. Renal replacement therapy (RRT) was required in both cases. In one patient, who died of late complications, sequencing of the HA1 segment revealed the previously described D222N mutation associated to severe cases. ARF with RRT appears to be an uncommon complication of patients hospitalized for influenza A H1N1pdm09 and may be secondary to acute glomerulonephritis.

La insuficiencia renal aguda (IRA) que requiere hemodiálisis no es una complicación común entre los pacientes afectados por influenza. Se comunican los casos clínicos de dos pacientes adultos fumadores no vacunados, que se internaron por influenza A H1N1pdm09 grave por shock y necesidad de ventilación mecánica. Ambos desarrollaron una falla renal progresiva con oliguria/anuria, asociada a un sedimento de orina inflamatorio con proteinuria, microhematuria y en un caso además con hipocomplementemia, sugiriendo una glomerulonefritis aguda. Se requirió terapia de reemplazo renal (TRR) en ambos casos. En uno de los pacientes, que falleció por complicaciones tardías, la secuenciación del segmento HA1 reveló la mutación D222N previamente descrita en casos graves. La IRA con TRR parece ser una complicación infrecuente de los pacientes ingresados por influenza A H1N1pdm09 y puede ser secundaria a una glomerulonefritis aguda.

Clinical relevance of rhinovirus infections among adult hospitalized patients

Human rhinovirus (HRV) is an emerging viral pathogen. Aim: To characterize a group of patients admitted due to infection by this agent in a general hospital in Chile. Methods: Cases were identified by RT-PCR for 1 year through active surveillance of patients admitted with severe respiratory illness. Diagnosis was not available during hospitalization. Thirty-two cases were identified, 90% were ≥60 years old or had co-morbid conditions. Human rhinovirus-related admissions represented 23.7% of hospitalization due to severe acute respiratory infections among adults and ranked second to influenza (37.8%). Patients presented with pneumonia (68.8%), decompensated chronic lung conditions (21.9%), heart failure or influenza-like illness (6.3% each). Admission to intensive or intermediate care units was required by 31.2% and in-hospital mortality reached 12.5%. A CURB-65 score ≥3 was significantly associated to in-hospital mortality (p < 0.05). Most patients received antibiotics (90%). Conclusions: Human rhinovirus infections in elderly patients with co-morbid conditions are associated with hospitalizations, requiring critical or semi-critical antibiotics use. A high CURB-65 score was associated to in-hospital mortality. .

Vigilancia de influenza en Chile: 2010 / Influenza surveillance in Chile: 2010

Se analizó el comportamiento de la influenza en el 2010, a través de los componentes de la vigilancia. Desde la semana epidemiológica (SE) 32 aumenta la notificación de ETI en los centinela, con un máximo de casos en la SE 37 (tasa 80 por 105), inferior a 2009. Este aumento coincide con el alza de las consultas respiratorias (especialmente infecciones respiratorias agudas altas e influenza) que llega a 43 por ciento en la SE 36. Destaca la cocirculación de influenza AH1N1 (2009) y H3N2, con predominio de esta última y un máximo en la SE 36. La gravedad (hospitalizaciones por infecciones respiratorias agudas graves y fallecidos) fue menor que en 2009 y se concentró en los casos de H3N2. El aumento observado el 2010 fue de intensidad elevada, de carácter epidémico, y se desplazó a los meses de agosto-septiembre. Se requiere mantener y reforzar los componentes de la vigilancia influenza en el actual período pospandémico.

It was analyzed the 2010 influenza behaviour through surveillance components. Since epidemiologic week (EW) 32, influenza like disease notification increases in sentinel centers, with a maximum of cases on EW 37 (rate of 80 per 105), less than2009. This increase coincide with the rise in respiratory hospital visits (especially upper acute respiratory infections) reaching 43 percent on EW 36. it is registered co-circulation of influenza AH1N1 (2009) and H3N2, the last prevailing over the first one anda maximum on EW 36. Severity (severe acute respiratory infections hospitalizations and deaths) was lower than 2009 and was concentrated in H3N2 cases. The observed increase in 2010 was of high intensity, epidemic nature and shifted to August-September. It is required maintaining and reinforcing influenza surveillance components, in the current pos-pandemic period.

Inicio del brote de Influenza A (H1N1) pandémica en Chile: caracterización genética de los primeros casos detectados / Genetic characterization of the virus causing H1N1 influenza pandemic in Chile: Analysis of the first detected cases

Background: Following the announcement of the Influenza A(H1N1) pandemic by the World Health Organization in April 2009, a surveillance program was carried out in Chile to detect the introduction of the virus in the country and to monitor its propagation and impact. Aim: To describe the onset of the outbreak and the genetic characterization of the pandemic H1N1 influenza virus in the first detected cases in Chile. Material and Methods: Analysis of18 clinical samples coming from suspicious patients, received in a National Reference Laboratory. RNA reverse transcription and real time influenza gene DNA amplification was carried out in a 7500 Fast and Step One Real Time PCR Systems of Applied Biosystems and MxPro-Mx3000P thermocycler from Stratagene. Super Script III Platinum One-Step Quantitative RT-PCR was used. Results: The virus was first detected in three persons returning from the Dominican Republic via Panamá and a child from the east zone of Santiago. Genetic characterization of the virus showed that the child was infected by a different variant of the pandemic virus than the three persons returning from the Caribbean. Conclusions: The onset of the Influenza outbreak in Chile apparently carne from two different epidemiological groups. The spread of the virus detected in the voyagers was limited immediately However the virus of the fourth case was found in different regions of Chile.

Descentralización del diagnóstico de influenza pandémica en Chile: implementación laboratorios regionales de RT-PCR / Decentralization of pandemic influenza diagnosis in Chile: implementing regional laboratories RT-PCR

Debido a la pandemia de influenza A (H1N1) en el mundo, el Ministerio de Salud en Chile desarrolló un proyectodestinado a fortalecer la capacidad de los laboratorios descentralizados, mediante utilización de la técnica de biología molecular RT-PCR. El proyecto contempló: 1) Readecuación de los espacios físicos en los laboratorios clínicos, 2) compra de equipamiento, 3) adquisición de reactivos e insumos de laboratorio, 4) adquisición de materiales para la toma de muestra, 5) capacitación del recurso humano y 6) verificación del correcto funcionamiento del laboratorio. Al 2010, se encuentran funcionando 6 laboratorios que emplean RT-PCR; se ha obtenido un 100 por ciento de concordancia de las muestras y las autoridades centrales han elaborado un algoritmo de derivación de muestras respiratorias por parte de los 29 Servicios de Salud a los laboratorios regionales, basado en grupos objetivos establecidos en la vigilancia de influenza.

Due to pandemic influenza A (H1N1) in the world, the Ministry of Health in Chile developed a project to strengthen decentralized laboratory capacity through the use of molecular biology technique RT-PCR. The project included: 1) Renovating the physical space in clinical laboratories, 2) purchasing equipment, 3) purchasing laboratory reagents and supplies, 4) acquiring materials for sample collection, 5) human resource training 6) verifying the proper functioning of the laboratory. By 2010, 6 laboratories employing RT-PCR are running, a 100 percent match of the samples has been obtained and the central authorities have developed an algorithm for derivation of respiratory specimens from the 29 Health Services to regional laboratories based on target groups established in the surveillance of influenza.