Factores de riesgo socio-demográficos del síndrome cardiopulmonar por hantavirus / Sociodemographic risk factors of hantavirus cardiopulmonary syndrome

Resumen Introducción: El síndrome cardiopulmonar por hantavirus (SCPH) es causado en Chile y en el sur de Argentina por el Andes hantavirus (ANDV), el que es endémico en esta zona. La enfermedad causada por ANDV produce un aumento de permeabilidad vascular y filtración de plasma con una alta tasa de letalidad (35%), debido principalmente a insuficiencia respiratoria por edema pulmonar y al desarrollo en los casos graves de compromiso miocárdico, hipoperfusión y shock. Aunque se sabe que los factores socio-demográficos del hospedero pueden influir en el curso y el resultado de la enfermedad, estos no se han caracterizado previamente en la población chilena. Objetivo: Evaluar la relación entre los factores socio-demográficos y la gravedad del SCPH. Pacientes y Métodos: Período de análisis 2004-20013, pacientes atendidos en ocho centros colaboradores, diagnóstico etiológico serológico o por biología molecular, se comparan SCPH leve y grave. Se analizaron 139 pacientes chilenos, 64 (46%) con enfermedad grave, entre los cuales 12 murieron (19%). Resultados: La etnia europea tuvo un riesgo 5,1 veces mayor de desarrollar un SCPH grave que la etnia amerindia, gravedad mayor que también se asoció a una residencia urbana. Conclusiones: Se observó una asociación estadísticamente significativa entre etnia, lugar de residencia y evolución de SCPH. Se discuten hipótesis que expliquen estos hallazgos.

Background: Hantavirus cardiopulmonary syndrome (HCPS) is caused by new world hantaviruses, among which Andes hantavirus (ANDV) is endemic to Chile and Southern Argentina. The disease caused by ANDV produces plasma leakage leading to enhanced vascular permeability and has a high case fatality rate (35%), mainly due to respiratory failure, pulmonary edema and myocardial dysfunction, hypoperfusion and shock. Host sociodemographic and genetic factors might influence the course and outcome of the disease. Yet, they have not been thoroughly characterized. Aim: To evaluate sociodemographic factors as risk factors in severity of HCPS. Patients and Methods: Study period: 2004-20013, attending in eight collaborative centers, etiological diagnosis was performed by serology or molecular biology, mild and severe HCPS were compared.139 Chilean patients were analyzed, 64 (46%) with severe disease among which 12 (19 %) died. Results: European ethnicity had 5,1 times higher risk than Amerindian ethnic group to develop a severe HCPS, greater seriousness that was also associated with an urban residence. Conclusion: It was observed that ethnicity and type of residence were significant risk factors for HCPS severity. Hypotheses explaining these findings are discussed.

Etiología viral en la neumonía del adulto adquirida en la comunidad en un hospital del sur de Chile / Viral etiology of community acquired pneumonia among adults admitted to a general hospital

Background: There is paucity of information about viral etiology of community acquired pneumonia in adults. Aim: To investigate the viral etiology of pneumonia among hospitalized patients. Material and Methods: All adults with pneumonia that were hospitalized were prospectively enrolled at Puerto Montt hospital. A microbiological and viral assessment was carried out. Viral assessment included direct immunofluorescence of nasopharyngeal aspirates for influenza A and B virus and serum samples obtained during the acute phase of the disease and during convalescence for Hanta virus. Results: Between April 1 2005 and March 31 2006,159 adults aged 62 ± 20 years (58 % males), were admitted to the hospital for pneumonia. Mean hospital stay was 11.9 ± 8.6 days. Four patients had Hantavirus acute infection. Other viruses were identified in twelve patients (7.7%). Nine had influenza A, one syncytial respiratory virus, one syncytial and influenza A virus and one varicella zoster virus. Excluding patients with Hantavirus, no significant differences in age, clinical presentation, chest X ray findings, laboratory results and mortality were observed between patients with bacterial or viral etiology of the pneumonia. Conclusions: Viral etiology was confirmed in 10% of adult patients hospitalized with community acquired pneumonia.