¿El reflujo gastroesofágico y la aspiración de contenido gástrico están implicados en la etiopatogenia y la progresión de la fibrosis pulmonar idiopática? / Does gastroesophageal reflux and gastric content aspiration have some role in the pathogenesis and progression of Idiopathic Pulmonary Fibrosis?

Resumen El reflujo gastroesofágico (RGE) y la aspiración oculta de contenido digestivo están probablemente implicados en la etiopatogenia y progresión de la fibrosis pulmonar idiopática (FPI). Los mecanismos patogénicos involucrados son la disminución de la distensibilidad pulmonar y el consiguiente aumento de la presión negativa intratorácica durante la inspiración, así como la disminución de los mecanismos de control de la motilidad esofágica o del tono del esfínter esofágico inferior. La prevalencia de RGE y anomalías de la motilidad esofágica están aumentadas en los pacientes con FPI comparado con la población general. Entre los pacientes con FPI, el 67-76% demostraron exposición anormal al contenido ácido en el esófago. Sin embargo, no hubo relación entre la gravedad del RGE y la gravedad de la FPI. Los estudios que han examinado el tratamiento antirreflujo en esta población han sido escasos. Incluso, algunos datos sugieren que el tratamiento antiácido puede ser perjudicial en algunos pacientes con esta condición. Después de analizar toda la evidencia relevante encontrada hasta la fecha, concluimos que no se puede establecer una relación causal entre el RGE, la aspiración del contenido gástrico y la patogénesis de la FPI. Además, existe escasa evidencia clínica que haya examinado el tratamiento antirreflujo en pacientes con fibrosis pulmonar idiopática.

ABSTRACT Gastroesophageal reflux (GERD) and hidden aspiration of gastric contents are probably involved in the pathogenesis and progression of idiopathic pulmonary fibrosis (IPF). The pathological mechanisms involved are decreased pulmonary distensibility and consequent increase of intrathoracic negative pressure during inspiration, as well as decreased control mechanisms of esophageal motility or lower esophageal sphincter. The prevalence of GERD and oesophageal dysmotility was higher in patients with IPF as compared with general population. Among patients with IPF, 67-76% demonstrated abnormal oesophageal acid exposure. However, no relationship was demonstrated between severity of GERD and severity of IPF. Data are scant on outcomes of antireflux treatment in patients with IPF. Actually, some data suggests that antacid treatment may be deleterious in some IPF patients. After analyzing all the relevant evidence found to date, a causal relationship between GERD, gastric content aspiration and IPF pathogenesis cannot be established. There is scant evidence examining antireflux treatment in idiopathic pulmonary fibrosis patients.

Uso de corticoides sistémicos en pacientes adultos hospitalizados por neumonía adquirida en la comunidad / Clinical efficacy of corticoids treatment in hospitalized adult patients with community-acquired pneumonia

Resumen La neumonía adquirida en la comunidad (NAC) es una enfermedad infecciosa común y potencialmente grave que ocasiona elevada morbilidad y mortalidad. La terapia con corticosteroides (CS) sistémicos se ha propuesto para el manejo de pacientes adultos hospitalizados por neumonía adquirida en la comunidad. Objetivos: Evaluar la eficacia y seguridad del tratamiento con corticosteroides sistémicos en pacientes con NAC grave. Métodos: Se buscó la información actualizada en cinco bases de datos: PubMed, Scielo, Epistemonikos, Lilacs y Cochrane Library. Se evaluaron los ensayos clínicos controlados aleatorizados que examinaron la eficacia y seguridad de los corticosteroides en adultos hospitalizados con NAC grave. Resultados: Se incluyeron diez revisiones sistemáticas y quince estudios primarios que reclutaron pacientes hospitalizados con NAC grave. La terapia con corticosteroides redujo significativamente la mortalidad por todas las causas (cociente de riesgo [RR]: 0,58; IC95%: 0,40 a 0,84), fracaso clínico precoz (RR: 0,32; IC95%: 0,15 a 0,7), riesgo de síndrome de dificultad respiratoria del adulto (RR: 0,23; IC95%: 0,07 a 0,80), necesidad de ventilación mecánica (RR: 0,40; IC95%: 0,20 a 0,77) y se acortó la estancia hospitalaria (diferencia media: −2.91 días; IC95%: − 4,92 a −0,89). La terapia esteroidal aumentó el riesgo de hiperglicemia (RR: 1,72; IC95%: 1,38 a 2,14) pero no la frecuencia de hemorragia gastrointestinal (RR: 0,91; IC95%: 0,40 a 2,05). Conclusión: La terapia con corticosteroides sistémicos disminuye significativamente la mortalidad, riesgo de complicaciones y acorta la estancia hospitalaria en pacientes con NAC grave. Estos resultados deben ser confirmados por estudios controlados aleatorizados de mayor potencia.

Community-acquired pneumonia (CAP) is a common and serious infectious disease accompanied with high morbidity and mortality. Corticosteroids (CS) therapy has been proposed for community-acquired pneumonia hospitalized adult patients. However, the effectiveness of adjunctive corticosteroids on relevant clinical outcomes of CAP remains inconsistent. Objectives: We assessed the efficacy and safety of adjunctive corticosteroids therapy in severe CAP patients. Methods: Five databases: PubMed, Scielo, Epistemonikos, Lilacs and Cochrane Library were searched for related studies published up to June, 2018. Randomized controlled trials (RCTs) of corticosteroids in hospitalized adults with severe CAP were included. Results: We assessed ten systematic reviews and fifteen primary studies enrolling severe CAP hospitalized patients. Corticosteroids therapy significantly reduced all-cause mortality (risk ratio (RR): 0.58; 95%CI: 0.40 to 0.84), early clinical failure (RR: 0.32; 95%CI: 0.15 to 0.7), risk of adult respiratory distress syndrome (ARDS) (RR: 0.23; 95%CI: 0.07 to 0.80), need for mechanical ventilation (RR: 0.40; 95%CI: 0.20 to 0.77) and decreased hospital length of stay (mean difference: −2.91 days; 95%CI: −4.92 to −0.89). Corticosteroids therapy increased hyperglycemia risk (RR: 1.72; 95%CI: 1.38 to 2.14) but not gastrointestinal hemorrhage frequency (RR: 0.91; 95%CI: 0.40 to 2.05). Conclusions: Adjuvant therapy with systemic corticosteroids decreases mortality, risk of hospital complications and shortens hospital length of stay in patients with severe CAP. These results should be confirmed by adequately powered studies in the future.

Predictores clínicos de eventos adversos serios en el adulto inmunocompetente hospitalizado por neumonía adquirida en la comunidad / Clinical predictors of serious adverse events in immunocompetent adult patients hospitalized with community-acquired pneumonia

Introducción: La neumonía adquirida en la comunidad (NAC) ocasiona morbilidad y mortalidad significativa en la población adulta. Objetivos: Examinar las variables clínicas y de laboratorio medidas en la admisión al hospital que permiten predecir los eventos adversos clínicamente relevantes en pacientes adultos hospitalizados por neumonía comunitaria. Métodos: Evaluamos las variables clínicas y de laboratorio asociadas a eventos adversos serios en una cohorte de adultos hospitalizados por NAC. Los eventos adversos examinados fueron la admisión a UCI, necesidad de ventilación mecánica, shock séptico, complicaciones cardiovasculares y generales y estadía prolongada en el hospital y mortalidad a 30 días. Las variables predictoras fueron sometidas a análisis univariado y multivariado en un modelo de regresión logística. Resultados: Se evaluaron 659 pacientes, edad: 67 ± 18 años, 52% varones, 77% tenía comorbilidad, 23% fueron admitidos a la UCI, 12% requirieron ventilación mecánica, 31% presentaron complicaciones en el hospital, la estadía media en el hospital fue 9 días y 9,9% fallecieron en el seguimiento a 30 días. Las comorbilidades, inestabilidad hemodinámica y disfunción renal se asociaron con la admisión a UCI, riesgo de complicaciones y estadía prolongada en el hospital. El uso de ventilación mecánica y shock séptico fue más frecuente en pacientes con inestabilidad hemodinámica y disfunción renal. La edad avanzada, enfermedades cardiovasculares y respiratorias crónicas, sospecha de aspiración, taquipnea y disfunción renal se asociaron al riesgo de eventos cardiovasculares en el hospital. Conclusión: Las variables clínicas y de laboratorio medidas en la admisión al hospital permiten predecir el riesgo de eventos adversos serios en el adulto hospitalizado por neumonía.

Introduction: Community-acquired pneumonia (CAP) causes significant morbidity and mortality in adult population. Objectives: To assess clinical and laboratory variables measured at hospital admission associated to clinically relevant adverse outcomes in patients hospitalized with community-acquired pneumonia. Methods: We prospectively assessed clinical and laboratory variables associated to serious adverse events in a cohort of CAP hospitalized adult patients. Major adverse outcomes were admission to ICU, need for mechanical ventilation, septic shock, prolonged hospital stay, cardiovascular and in-hospital complications and 30-day mortality. The clinical and laboratory variables measured at hospital admission associated to serious adverse events were assessed by univariate and multivariate analysis using logistic regression models. Results: 659 CAP hospitalized immunocompetent adult patients were assessed, mean age: 67 years, 52% were male, 77% had comorbidities, 23% were admitted to the intensive care unit (ICU), 12% needed mechanical ventilation, 31% had hospital complication, mean hospital length of stay was 9 days and 9.9% died at 30-days follow up. Comorbidities, hemodynamic instability and renal dysfunction were associated with ICU admission, risk of complications, and prolonged hospital stay. Mechanical ventilation requirement and septic shock were more frequent in patients with hemodynamic instability and renal dysfunction. Advanced age, chronic cardiovascular and respiratory diseases, aspiration pneumonia, tachypnea, and renal dysfunction were associated with high risk of cardiovascular events in the hospital. Conclusion: The clinical and laboratory variables measured at hospital admission allow us to predict the risk of serious adverse events in CAP hospitalized adult patients.

Detección precoz de cáncer pulmonar con tomografía computarizada de tórax en pacientes con enfermedad pulmonar obstructiva crónica tabáquica / Early detection of lung cancer using computed tomography among patients with chronic obstructive pulmonary disease

Background: Chest computed tomography (CT) scan may improve lung cancer detection at early stages in high risk populations. Aim: To assess the diagnostic performance of chest CT in early lung cancer detection in patients with chronic obstructive pulmonary disease (COPD). Patients and Methods: One hundred sixty one patients aged 50 to 80 years, active or former smokers of 15 or more pack-years and with COPD were enrolled. They underwent annual respiratory functional assessment and chest computed tomography for three years and were followed for five years. Results: Chest CT allowed the detection of lung cancer in nine patients (diagnostic yield: 5.6%). Three cases were detected in the initial CT and six cases in follow-up scans. Most patients were in early stages of the disease (6 stage Ia and 1 stage Ib). Two patients were diagnosed at advanced stages of the disease and died due to complications of cancer. Two thirds of patients had nonspecific pulmonary nodules on the initial chest CT scan (100 patients, 62%). Seventy four percent had less than three nodules and were of less than 5 mm of diameter in 57%. In 92% of cases, these were false positive findings. In the follow-up chest CT, lung nodules were detected in two thirds of patients and 94% of cases corresponded to false positive findings. Conclusions: Chest CT scans may detect lung cancer at earlier stages in COPD patients.

Predictores clínicos de bacteriemia en adultos inmunocompetentes hospitalizados por neumonía adquirida en la comunidad / Clinical predictors of bacteremia in immunocompetent adult patients hospitalized for community-acquired pneumonia

Background: The clinical usefulness of blood cultures in the management of patients hospitalized with community-acquired pneumonia (CAP) is controversial. Aim: To determine clinical predictors of bacteremia in a cohort of adult patients hospitalized for community-acquired pneumonia. Material and Methods: A prospective cohort of 605 immunocompetent adult patients aged 16 to 101 years (54% male) hospitalized for CAP was studied. The clinical and laboratory variables measured at admission were associated with the risk of bacteremia by univariate and multivariate analysis using logistic regression models. Results: Seventy seven percent of patients had comorbidities, median hospital stay was 9 days, 7.6% died in hospital and 10.7% at 30 days. The yield of the blood cultures was 12.6% (S. pneumoniae in 69 patients, H. influenzae in 3, Gram negative bacteria in three and S. aureus in one). These results modified the initial antimicrobial treatment in one case (0.2%). In a multivariate analysis, clinical and laboratory variables associated with increased risk of bacteremia were low diastolic blood pressure (Odds ratio (OR): 1.85, 95% confidence intervals (CI) 1.02 to 3.36, p < 0.05), leukocytosis e" 15,000/mm³ (OR: 2.18, 95% CI 1.22 to 3.88, p < 0.009), serum urea nitrogen e" 30 mg/dL (OR: 2.23, 95% CI 1.22 to 4.05, p < 0.009) and serum C-reactive protein e" 30 mg/dL (OR: 2.20, 95% CI 1.22 to 3.97, p < 0.01). Antimicrobial use before hospital admission significantly decreased the blood culture yield (OR: 0.14, 95% CI 0.04 to 0.46, p < 0.002). Conclusions: Blood cultures do not contribute significantly to the initial management of patients hospitalized for community-acquired pneumonia. The main clinical predictors of bacteremia were antibiotic use, hypotension, renal dysfunction and systemic inflammation.

Factores pronósticos y sobrevida a mediano plazo de una cohorte de pacientes con cáncer pulmonar atendidos en la red de salud de la Universidad Católica: Período 2007-2011 / Prognostic factors and short-term survival of a cohort of adult patients with lung cancer treated in a network of health, 2007-2011

Lung cancer is the leading cause of death from malignancy worldwide. In Chile the magnitude of the problem and the diagnosis-associated survival are unknown. Methods: We examined a cohort of 202 adult patients with lung cancer histologically confirmed in a single health network between January 2007 and December 2011. We accessed to medical records and images files of patients, recording the clinical, histological, imaging and staging data. Patients were followed until December 2013 to assess survival. Results: The mean age of the cohort was 68.1 ± 11.5 years, 53% were male and 86% had a smoking history. 82.2% of the cases were symptomatic at diagnosis, been cough the symptom most frequently reported. The predominant histological subtype was adenocarcinoma (42%), followed by squamous cell carcinoma (26.2%). In women, adenocarcinoma was the leading histology variety (56.4%), and in males it was adenocarcinoma (37%) and squamous cell carcinoma (33.3%). The majority of the patients were diagnosed at advanced stages of the disease. The 36-month survival rate was 46.1%. The mean survival according to clinical stage was 70.7 month in stage I, 60.3 in stage II, 47.1 in IIIA, 12.3 in IIIB and 11.7 month in stage IV. According to histological variety, the mean survival was 36.6 month in adenocarcinoma, 33.8 in squamous cell carcinoma, 20.9 in large-cell carcinoma, 11.9 in small-cell carcinoma and 19.6 month in undifferentiated non small-cell carcinoma. There were no significant differences in survival by age or gender. Conclusion: The most common histological type was adenocarcinoma and short-term survival was related to the clinical staging and histological variants.

El cáncer pulmonar es la principal causa de muerte por neoplasia a nivel mundial. En Chile se desconoce la magnitud del problema y la sobrevida asociada al diagnóstico. Material y Métodos: Se examinó una cohorte de 202 pacientes adultos con cáncer pulmonar confirmados histopatológicamente en una red de salud entre Enero de 2007 y Diciembre de 2011. Se accedió a las fichas clínicas y archivos de imágenes de los pacientes, registrando las variables clínicas, histológicas, imagenológicas y la etapificación clínica. Se siguió prospectivamente a los pacientes hasta Diciembre de 2013 para determinar sobrevida. Resultados: La edad promedio de la cohorte fue de 68,1 ± 11,5 años, 53% eran varones y 86% tenía historia de tabaquismo. El 82,2% de los casos presentaron síntomas al momento del diagnóstico, siendo la tos el más frecuente. La variedad histológica preponderante fue el adenocarcinoma (42%), seguido del carcinoma escamoso (26,2%). En las mujeres la mayoría de los tumores correspondieron a adenocarcinomas (56,4% del total) y en varones predominaron el adenocarcinoma (37%) y el carcinoma escamoso (33,3%). La mayoría de los pacientes se diagnosticaron en estadios avanzados de la enfermedad. La sobrevida global a los 36 meses fue 46,1%. La sobrevida media por estadio clínico fue de 70,7 meses en el estadio I, 60,3 meses en estadio II, 47,1 meses en IIIA, 12,3 meses en IIIB y 11,7 meses en IV Según histología, la sobrevida media en meses fue de 36,6 en adenocarcinoma, 33,8 en carcinoma escamoso, 20,9 en células grandes, 11,9 en células pequeñas y 19,6 en tumor no células pequeñas indiferenciado. No hubo diferencias significativas en la sobrevida por edad y género. Conclusión: La variedad histológica más frecuente es el adenocarcinoma y la sobrevida está relacionada a la etapificación clínica y variedad histológica.

Dificultades en la elección de una ecuación de referencia para la interpretación de los resultados de capacidad de difusión de monóxido de carbono / Difficulties in the selection of a reference equation for the interpretation of the results of DLCO

Introduction: In the absence of national reference equations, the ATS recommends comparing the results of the diffusion capacity of healthy subjects in a representative sample of the population with international equations and choosing among them, the one that provides the lowest sum of the residues. Objective: To compare reference equations available in the literature and identify which best meets the selection criteria. Methods: We reviewed 10 reference equations, for each one we calculated the sum of the residues for a sample of 71 healthy subjects and described the characteristics that affect the variability of each one. Results: Since 1985 we have used the single breath method. Only Thompson et al prediction equations 2008 were obtained with instantaneous reading of CO. Equations with the lowest sum of residues (Miller, Roca and Cotes) include smokers and former smokers. Conclusions: We need an equation in non-smokers with methodology that ensures low variability.

Introducción: En ausencia de ecuaciones de referencia nacionales, la ATS recomienda comparar los resultados de capacidad de difusión de monóxido de carbono de sujetos sanos en una muestra representativa de la población, con ecuaciones internacionales y escoger entre estas, aquella que presente la menor suma de los residuos. Objetivo: Comparar las ecuaciones de referencia disponibles en la literatura e identificar cuál cumple mejor los criterios de selección. Método: Revisamos 10 ecuaciones de referencia; calculamos la suma de los residuos de cada una de ellas para una muestra de 71 sujetos sanos y describimos las características que inciden en la variabilidad de cada una. Resultados: Desde 1985 se ha utilizado el método de respiración única. Sólo las ecuaciones de Thompson y cols. 2008fueron obtenidas con lectura instantánea. Las ecuaciones que presentan menor suma de residuos (Miller, Roca y Cotes) incluyen fumadores y ex fumadores. Conclusiones: Es necesaria una ecuación nacional en sujetos sanos no fumadores, con metodología que asegure baja variabilidad.

Programa de incentivo de la actividad física apoyado con contadores de pasos en la enfermedad pulmonar obstructiva crónica / A program of physical activity enhancement using pedometers in chronic obstructive pulmonary disease

Introducción: La actividad física diaria está reducida en la EPOC lo que se asocia a una mayor morbimortalidad. La indicación médica de caminar más se ha demostrado poco eficaz y, en nuestro medio, se desconoce el beneficio del uso de los contadores de pasos en la EPOC. Objetivo: Determinar el efecto de los contadores de pasos para incentivar la actividadfísica en la EPOC. Método: 55 Pacientes con EPOC fueron incorporados a un programa de tres meses destinado a aumentar su actividad física y fueron asignados aleatoriamente a dos grupos: en uno el paciente autocontroló su actividad con un contador de pasos (grupo experimental) y en el otro se siguió el manejo habitual (grupo control). Al comienzo y al final del estudio se realizaron las siguientes mediciones: promedio de pasos caminados por día medidos en una semana, espirometría, caminata de seis minutos (C6M), disnea con escala de la Medical Research Council Modificada (mMRC) y calidad de vida mediante cuestionario de Saint George (SGRQ) y COPD Assessment Test (CAT). Resultados: 69 por ciento de los pacientes eran hombres, edad promedio 68 años, VEF1ICVF = 55 por ciento, VEF(1)63 por ciento predicho. El grupo experimental (n = 29) y el control (n = 26) presentaron características basales comparables. El grupo experimental presentó una diferencia significativa en el incremento de los pasos por día en comparación con el grupo control (mediana de 2073,5 versus -68, p < 0,001). También hubo diferencia en la reducción del componente síntomas del SGRQ (promedio de -9,65 versus 0,05 puntos, grupo experimental versus control, p = 0,048). Conclusión: Un programa de incentivo de la actividad física apoyado con contadores de pasos es útil para incentivar la actividad física en la EPOC.

Introduction: The level of daily physical activity is reduced in COPD and has a negative effect on the morbidity and mortality of this condition. Usual advice is not sufficient to reverse the sedentary condition. Pedometers are widely used but their effects in COPD have not been tested in our country. Aim: To determine the effect of pedometers on physical activity in COPD patients. Method: 55 COPD patients were recruited for a 3 months individual program promoting daily physical activity enhancement and were randomly assigned either to a pedometer-based program (experimental group) or to usual care (control group). At the beginning and at the end of the intervention period we measured the average daily steps over one week, exercise capacity using the six-minute walking test (6MWT), the MMRC dyspnoea score, the Saint George Respiratory Questionnaire (SGRQ) and the COPD assessment Test (CAT) to estimate quality of life. Results: 69% of the subjects were male, mean age 68 years, mean FEV1IFVC 55%, mean FEV163% of predicted value. Experimental (n = 29) and control group (n = 26) had comparable baseline characteristics. There was a significant difference in the increase of steps/day in the experimental group in comparison with the control group (median value = 2073.5 versus -68, p < 0.001). Also, a significant difference was observed in the symptoms subscale score of the SGRQ (reduction of 9.65 versus 0.05points, experimental versus control group, p = 0.048). Conclusions: Pedometers are a useful tool to increase physical activity level in COPD.

Infección pulmonar por mycobacterium avium complex en el huésped inmunocompetente / Mycobacterium avium complex pulmonary disease in immunocompetent adult patients

Las micobacterias no tuberculosas (MNT) se reconocen cada vez más como importantes patógenos pulmonares. El complejo Mycobacterium avium-intracellulare (MAC) causa la mayoría de las infecciones pulmonares por MNT. Aunque el organismo fue identificado en la década de 1890, su potencial patogenicidad en seres humanos fue reconocida sólo cincuenta años después. Los pacientes con enfermedad pulmonar preexistente o inmunodeficiencia están en mayor riesgo de desarrollar infección por MAC. Sin embargo, la mayoría de los casos se producen en mujeres de edad avanzada inmunocompetentes en asociación con infiltrados nodulares y bronquiectasias. Recientemente, la enfermedad pulmonar también se ha descrito en pacientes inmunocompetentes expuestos a equipos de hidroterapia o jacuzzis contaminados con MAC. En relación a dos pacientes adultos inmunocompetentes con enfermedad pulmonar por MAC examinamos el cuadro clínico, los criterios diagnósticos y el tratamiento de esta entidad.

Nontuberculous mycobacteria (NTM) are increasingly recognized as important pulmonary pathogens. Mycobacterium avium intracellulare complex (MAC) causes most lung infections due to NTM. Although the organism was identified in the 1890s, its potential to cause human disease was only recognized 50 years later. Patients with preexisting lung disease or immunodeficiency are at greatest risk for developing MAC infection. The majority of MAC pulmonary cases, however, occur in immunocompetent elderly women in association with nodular infiltrates and bronchiectasis. More recently, pulmonary disease has also been described in immunocompetent patients after exposure to MAC-contaminated hot tubs. We describe two cases of MAC lung disease in immunocompetent adult patients without preexisting lung disease and we review clinical manifestations, diagnostic criteria and treatment of this entity.

Sobrevida a largo plazo en adultos inmunocompetentes mayores de 60 años hospitalizados por neumonía adquirida en la comunidad / Long-term survival of immunocompetent patients older than 60 years hospitalized for community-acquired pneumonia

Background: A reduction in long-term survival of adult patients hospitalized with community-acquired pneumonia (CAP), especially older people with múltiple comorbidities, has been reported. Aim: To examine the clinical variables associated to mortality at 72 months of adult patients older than 60 years hospitalized with CAP and compare their mortality with a control group matched for age, gender and place of admission. Material and Methods: Prospective assessment of 465 immunocompetent patients aged 61 to 101 years, hospitalized for CAP in a teaching hospital. Hospital and 30 day mortality was obtained from medical records. Seventy two months survival ofthe 424 patients who were discharged olive, was compared with a group of 851 patients without pneumonia paired for gender and age. Mortality at 72 months was obtained from death certificates. Results: Eighty seven percent of patients had comorbidity. The median hospital length ofstay was 10 days, 8.8% died in the hospital, 29.7% at one year follow-up and 61.9%o at 6 years. The actuarial survival at six years was similar in the cohort of adults hospitalized with CAP and the control group matched for age, gender and site of care. In a multivariate analysis, the clinical variables associated with increased risk of dying during long-term follow-up were older age, chronic cardiovascular and neurological diseases, malignancy, absence of fever, low C-reactive protein at hospital admission and high-risk parameters of the Fine índex. Conclusions: Advanced age, some specific comorbidities, poor systemic inflammatory response at admission and high risk parameters of the Fine Index were associated to increased risk of dying on long-term follow-up among older adults hospitalized for CAP.

Predictores clínicos de mortalidad en el seguimiento a mediano plazo en pacientes adultos inmunocompetentes hospitalizados por neumonía adquirida en la comunidad / Predictors of one year mortality among immunocompetent adults hospitalized for community-acquired pneumonia

Background: Mortality increases in adults, especially in older adults, after recovery from an episode of community-acquired pneumonia (CAP). Aim: To analyze survival and predictors of death at one year follow up of a cohort of adult patients hospitalized with CAP. Material and Methods: Immunocompetent patients admitted to a clinical hospital for an episode of CAP were included in the study and were assessed according to a standardized protocol. One year mortality after admission was assessed using death records of the National Identification Service. Clinical and laboratory variables measured at hospital admission associated with risk of death at one year follow up were subjected to univariate and multivariate analysis by a logistic regression model. Results: We evaluated 659 patients aged 68 ± 19 years, 52% were male, 77% had underlying conditions (especially cardiovascular, neurological and respiratory diseases). Mean hospital length of stay was 9 days, 7.1% died during hospital stay and 15.8% did so during the year of follow-up. A causal agent was identified in one third of cases. The main pathogens isolated were Streptococcus pneumoniae (12.9%), Haemophilus influenzae (4.1%), respiratory viruses (6.5%) and Gram-negative bacilli (6.5%). In multivariate analysis, the clinical variables associated with increased risk of dying during the year of follow-up were older age, chronic neurological disease, malignancies, lack of fever at admission and prolonged hospital length of stay. Conclusions: Age, specific co-morbidities such as chronic neurological disease and cancer, absence of fever at hospital admission and prolonged hospital length of stay were associated with increased risk of dying during the year after admission among adult patients hospitalized with community-acquired pneumonia.

Etiología y biomarcadores de inflamación sistémica en las exacerbaciones leves a moderadas de la enfermedad pulmonar obstructiva crónica / Etiology and biomarkers of systemic inflammation in mild to moderate COPD exacerbations

Background: The etiology of acute exacerbations of chronic obstructive pulmonary disease (COPD) is heterogeneous and still under discussion. Inflammation increases during exacerbation of COPD. The identification of inflammatory changes will increase our knowledge and potentially guide therapy. Aim: To identify which inflammatory parameters increase during COPD exacerbations compared to stable disease, and to compare bacterial and viral exacerbations. Material and Methods: In 85 COPD patients (45 males, mean age 68 ± 8 years, FEV1 46 ± 17% of predicted) sputum, nasopharyngeal swabs and blood samples were collected to identify the causative organism, during a mild to moderate exacerbation. Serum ultrasensitive C reactive protein (CRP), fibrinogen and interleukin 6 (IL 6), neutrophil and leukocyte counts were measured in stable conditions, during a COPD exacerbation, 15 and 30 days post exacerbation. Results: A total of 120 mild to moderate COPD exacerbations were included. In 74 (61.7%), a microbial etiology could be identified, most commonly Mycoplasma pneumoniae (15.8%), Rhinovirus (15%), Haemophilus influenzae (14.2%), Chlamydia pneumoniae (11.7%), Streptococcus pneumoniae (5.8%) and Gram negative bacilli (5.8%). Serum CRP, fibrinogen and IL 6, and neutrophil and leukocyte counts significantly increased during exacerbation and recovered at 30 days post exacerbation. Compared to viral exacerbations, bacterial aggravations were associated with a systemic inflammation of higher magnitude. Conclusions: Biomarkers of systemic inflammation increase during mild to moderate COPD exacerbations. The increase in systemic inflammation seems to be limited to exacerbations caused by bacterial infections.

Evaluación clínico-radiológica y clasificación de la bronquiolitis del adulto / Bronchiolar disorders: clinical-radiological assessment and classification

Bronchiolar disorders are generally difficult to diagnose. A detailed clinical history may point toward a specific diagnosis. Pertinent clinical questions include history of smoking, collagen vascular disease, inhalation injury, medication use and organ transplantation. It is important also to evaluate possible systemic and pulmonary signs of infection, evidence of air trapping, and high-pitched expiratory wheezing, which may suggest small airways involvement. Pulmonary function tests and plain chest radiography may demonstrate abnormalities; however, they rarely prove sufficiently specific to obviate bronchoscopic or surgical biopsy. High-resolution CT (HRCT) scanning of the chest is often an important diagnostic tool to guide diagnosis in these difficult cases, because different subtypes of bronchiolar disorders may present with characteristic image findings. Some histopathologic patterns of bronchiolar disease may be relatively unique to a specific clinical context but others are nonspecific with respect to either etiology or pathogenesis. Primary bronchiolar disorders include acute bronchiolitis, respiratory bronchiolitis, follicular bronchiolitis, mineral dust airway disease, constrictive bronchiolitis, diffuse panbronchiolitis, and other rare variants. Prominent bronchiolar involvement may be seen in several interstitial lung diseases, including hypersensitivity pneumonitis, collagen vascular disease, respiratory bronchiolitis-associated interstitial lung disease, cryptogenic organizing pneumonia, and pulmonary Langerhans’ cell histiocytosis. Large airway diseases that commonly involve bronchioles include bronchiectasis, asthma, and chronic obstructive pulmonary disease. The clinical and prognostic significance of a bronchiolar lesion is best determined by identifying the etiology, underlying histopathologic pattern and assessing the correlative clinic-physiologic-radiologic context.

Índices predictores de eventos adversos en el adulto inmunocompetente hospitalizado por neumonía neumocóccica adquirida en la comunidad / Severity scores for predicting clinically relevant outcomes for immunocompetent adult patients hospitalized with community-acquired pneumococcal pneumonia

Streptococcus pneumoniae is the main cause of community-acquired pneumonia (CAP) in adults. Objectives: To compare accuracy and discriminatory power of three validated rules for predicting clinically relevant adverse outcomes in patients hospitalized with community-acquired pneumococcal pneumonia. Measurements: We pros-pectively compared the pneumonia severity index (PSI), British Thoracic Society score (CURB-65) and severe CAP score (SCAP) in a cohort of 151 consecutive immunocompetent adult patients hospitalized with pneumo-coccal pneumonia. Major adverse outcomes were admission to ICU, need for mechanical ventilation, in-hospital complications and 30-day mortality. Mean hospital length of stay (LOS) was also evaluated. The predictive indexes were compared based on sensitivity, specificity, and area under the curve of the receiver operating characteristic. Results: The mean age of 151 immunocompetent adult patients hospitalized with pneumococcal pneumonia was 64 years (range, 16 to 92); 58 percent were male, 75 percent had comorbidities, 26 percent were admitted to the intensive care unit and 9 percent needed mechanical ventilation. The rate of all adverse outcomes and hospital LOS increased directly with increasing PSI, CURB-65 and SCAP scores. The three severity scores allowed us to predict the risk of in-hospital complications and 30-day mortality. The PSI score was more sensitive and the SCAP was more specific to predict in-hospital complications and the risk of death. However, the SCAP was more sensitive and specific in predicting the use of mechanical ventilation. Conclusion: The severity scores validated in the literature allow us to predict the risk of complications and death in adult patients hospitalized with pneumococcal pneumonia. Nevertheless, the clinical indexes differ in their sensitivity, specificity and discriminatory power to predict different adverse events.

Streptococcus pneumoniae es el principal agente causal de la neumonía adquirida en la comunidad. Objetivos: Examinar el poder discriminativo de tres índices pronósticos en la predicción de eventos adversos clínicamente relevantes en pacientes hospitalizados por neumonía neumocóccica adquirida en la comunidad. Métodos: Evaluamos el índice de gravedad de la neumonía (IGN), CURB-65 y el índice de neumonía grave adquirida en la comunidad (INGAC) en una cohorte de 151 adultos inmunocompetentes hospitalizados por neumonía neu-mocóccica. Los eventos adversos examinados fueron la admisión a UCI, necesidad de ventilación mecánica, complicaciones en el hospital y mortalidad a 30 días. Las reglas predictoras fueron comparadas en base a su sensibilidad, especificidad y área bajo la curva receptor operador. Resultados: Se evaluaron 151 pacientes (64 ± 18 años), 58 por ciento varones, 75 por ciento tenía co-morbilidad, 26 por ciento fueron admitidos a la UCI y 9 por ciento requirieron ventilación mecánica. La tasa de eventos adversos fue más elevada y la estadía en el hospital más prolongada en las categorías de alto riesgo de los tres índices predictores. Los tres índices permitieron, a su vez, predecir el riesgo de complicaciones y muerte en el seguimiento a 30 días. El IGN fue más sensible y el INGAC más específico en la pesquisa de complicaciones en el hospital y en predecir el riesgo de muerte. El INGAC fue más sensible y específico en predecir el uso de ventilación mecánica. El CURB-65 tuvo menor poder discriminatorio comparado con el IGN e INGAC. Conclusión: Los índices pronósticos validados en la literatura médica permiten predecir el riesgo de complicaciones y muerte en el adulto hospitalizado por neumonía neumocóccica. Sin embargo, difieren en su sensibilidad, especificidad y poder discriminatorio de los distintos eventos adversos.

Bases fisiopatológicas del entrenamiento muscular en pacientes con enfermedad pulmonar obstructiva crónica / Pathophysiological bases of muscular training in patients with chronic obstructive pulmonary disease

Dyspnea and decreased exercise capacity are the main factors that limit the daily living activities in patients with chronic respiratory diseases. The cardinal symptoms limiting exercise capacity in most patients with chronic obstructive pulmonary disease (COPD) are dyspnea and fatigue, which could be caused by alveolar ventilation and gas exchange disturbances, skeletal muscle dysfunction and/or cardiovascular failure. Anxiety, lack of motivation and depression were also associated with reduced exercise capacity, probably affecting the perception of symptoms. The relationship between psychological status and mood disorders in patients with COPD and exercise tolerance is complex and not yet fully understood. The origin of the exercise capacity limitation in COPD patients is multifactorial, so the separation of the variables involved for academic purposes is not always feasible. The pathogenic mechanisms may interact in complex ways, as an example, muscle deconditioning and hypoxemia can increase alveolar ventilation causing exercise limitation. Therefore, physical training and supplemental oxygen can reduce ventilatory limitation during exercise without changing lung function and maximum ventilatory capacity. The analysis of these factors could potentially identify reversible conditions that can improve the exercise performance and quality of life ofpatients with COPD, such as hypoxemia, bronchospasm, heart failure, arrhythmias, musculoskeletal dysfunction and myocardial ischemia. This review examines the principal mechanisms contributing to physical activity limitation in patients with COPD: alveolar ventilation and gas exchange abnormalities, cardiovascular and musculoskeletal system dysfunction, and respiratory muscles dysfunction.

La disnea y la disminución de la capacidad de realizar ejercicio son los principales factores que limitan las actividades de la vida diaria en pacientes con enfermedades respiratorias crónicas. Los síntomas cardinales que limitan la capacidad de ejercicio en la mayoría de los pacientes con enfermedad pulmonar obstructiva crónica (EPOC) son la disnea y/o fatigabilidad, los cuales pueden ser ocasionados por trastornos de la ventilación alveolar e intercambio gaseoso, disfunción de los músculos esqueléticos y/o falla cardiovascular. La ansiedad, falta de motivación y depresión también han sido asociadas a una menor capacidad de realizar ejercicio, probablemente afectando la percepción de los síntomas. La relación entre el estado psicológico y los trastornos del ánimo en pacientes con EPOC y la tolerancia al ejercicio es compleja y aún no ha sido completamente dilucidada. El origen de la limitación de la capacidad de ejercicio en pacientes con EPOC es multifactorial, por lo cual la separación de las variables involucradas con fines académicos no siempre es factible realizarlo en los pacientes. Los mecanismos patogénicos pueden relacionarse en forma compleja, a modo de ejemplo, el desacondicionamiento físico y la hipoxemia pueden contribuir a aumentar la ventilación alveolar ocasionando limitación del ejercicio de causa ventilatoria. Por lo tanto, el entrenamiento físico y el suplemento de oxígeno pueden reducir la limitación ventilatoria durante el ejercicio sin modificar la función pulmonar o la capacidad ventilatoria máxima. El análisis de los factores limitantes de la capacidad de ejercicio permite identificar trastornos potencialmente reversibles que pueden mejorar la calidad de vida de los enfermos, tales como la hipoxemia, broncoespasmo, insuficiencia cardiaca, arritmias, disfunción musculoesquelética y/o isquemia miocárdica. En esta revisión se examinan los principales mecanismos que contribuyen a la limitación de la actividad física en pacientes con EPOC:...

Evaluación prospectiva de la venografía mediante angioTC en el diagnóstico de enfermedad tromboembólica / Diagnostic yield of CT pulmonary angiography and venography for thromboembolic disease

Background: CT pulmonary angiography is the diagnostic procedure of choice for non-massive pulmonary embolism. Aim: To assess the diagnostic yield for thromboembolic disease of CT pulmonary angiography and venography using a 64- slice multidetector tomography. Material and Methods: Prospective study of patients with a clinical suspicion of thromboembolic disease, subjected to CT pulmonary angiography and venography. The presence and location of pulmonary thromboembolism, of isolated or concomitant deep venous thrombosis and of other significant radiological findings, were registered. Results: A 64-MDCT scanner was performed to 893 patients and thromboembolic disease was demonstrated in 240. Pulmonary thromboembolism was diagnosed in 218 patients. It was concomitant with deep venous thrombosis in 79 patients (36 percent) and isolated in the rest. Thirty fve of the 218 patients with pulmonary thromboembolism had radiological evidence of right ventricular overload. Twenty two patients (10 percent) had an isolated deep venous thrombosis. In 65 patients with pulmonary thromboembolism (30 percent) a possibly new or old malignant lesion, was observed. Seventy one of 653 patients without evidence of thromboembolic disease had potentially pathological findings on CT. Conclusions: The combined use of CT pulmonary arteriography and venography using a 64 MDCT scanner increases the diagnostic yield of the procedure for thromboembolic disease. It also allows the diagnosis of other related conditions, specially malignant tumors.

Prueba de caminata en seis minutos en sujetos chilenos sanos de 20 a 80 años / Reference values for the 6-minutes walking test in healthy subjects 20-80 years old

Background: The six minute walking distance test (6MWD) is widely used to evaluate exercise capacity in several diseases due to its simplicity and low cost. Aim: To establish reference values for 6MWD in healthy Chilean individuals. Material and methods: We studied 175 healthy volunteers aged 20-80 years (98 women) with normal spirometry and without history of respiratory, cardiovascular or other diseases that could impair walking capacity. The test was performed twice with an interval of 30 min. Heart rate, arterial oxygen saturation (with a pulse oxymeter) and dyspnea were measured before and after the test. Results: Walking distance was 576 ± 87 m in women and 644 ± 84 m in men (p < 0.0001). For each sex, a model including age, height and weight produced 6MWD prediction equations with a coefficient of determination (R²) of 0.63 for women and 0.55 for men. Conclusions: Our results provide reference equations for 6MWD that are valid for healthy subjects between 20 and 80 years old.

Valor predictivo de la historia clínica y oximetría nocturna en la pesquisa de pacientes con apneas obstructivas del sueño / Predictive value of clinical features and nocturnal oximetry for the detection of obstructive sleep apnea syndrome

Background: Obstructive sleep apnea syndrome (OSA) is an important cause of morbidity and mortality in adults. Aim: To evaluate the diagnostic value of clinical features and oximetric data to screen for obstructive sleep apnea before performing polysomnograpy or respiratory polygraphy. Material and Methods: We studied 328 consecutive adult patients referred for snoring or excessive daytime sleepiness to a sleep clinic in whom a standardized questionnaire and the Sleepiness Epworth Scale were performed and body mass index (BMI), cervical circumference (CC), and nocturnal oximetry were measured. Results: Fifty three percent (n = 173) had evidence of clinically significant OSA (apnea/hypopnea index (AHI) > 15 events/h). Patients with OSA were more likely to be male, obese (BMI ≥ 26 kg/m²), smokers, to have a thick neck (CC > 41 cm), and to have a significant greater prevalence of relative reported apneas and excessive daytime sleepiness, as determined by Epworth scale. Male gender (Odds ratio (OR): 4.00; 95 percent confidence intervals (CI): 1.59-10.0, p = 0.003), BMI ≥ 26 kg/m² (OR: 3.68; 95 percentCI: 1.59-8.49, p = 0.002), smoking (OR: 2.29; 95 percent CI: 1.17-4.47, p = 0.015), Epworth index > 13 (OR: 2.65; 95 percent CI: 1.35-5.23, p = 0.005) and duration of symptoms over 2 years (OR: 2.35; 95 percent CI: 1.20-4.58, p = 0.012) were significant independent predictors of OSA. In nocturnal oximetry, the lowest SpO2 (SpO2 min) and the length of registries below 90 percent (CT-90) were independent predictors of OSA and both correlated significantly with AHI (r = -0.49 and r = 0.46 respectively, p < 0.001). Conclusions: No single factor was usefully predictive of obstructive sleep apnea. However, combining clinical features and oximetry data may be appropriate to detect clinically significant OSA patients.

Marcadores de inflamación sistémica en pacientes ex fumadores con enfermedad pulmonar obstructiva crónica en etapa estable / Systemic inflammation among stable ex smokers with chronic obstructive pulmonary disease

Background: Low grade systemic inflammation is commonly observed in chronic obstructive pulmonary disease (COPD). Aim: To evaluate the extent of systemic inflammation in a group of ex-smokers with COPD in stable condition and its relation with pulmonary function and clinical manifestations. Patients and Methods: We studied 104 ex-smokers aged 69 ± 8 years (62 males) with mild to very severe COPD and 52 healthy non-smoker subjects aged 66 ± 11 years (13 males) as control group. High sensitivity serum C reactive protein (CRP), interleukin 6 (IL6), fibrinogen (F) and neutrophil count (Nc) were measured. Forced expiratory volume in the first minute (FEV1), inspiratory capacity (IC), arterial blood gases, six minutes walking test, dyspnea and body mass index (BMI) were measured, calculating the BODE index. Health status was assessed using the Saint George Respiratory Questionnaire (SGRQ), the chronic respiratory questionnaire (CRQ), registering the number of acute exacerbations (AE) during the previous year and inhaled steroids’s use. Systemic inflammation was considered present when levels of CRP or IL6 were above the percentile 95 of controls (7.98 mg/L and 3.42 pg/ml, respectively). Results: COPD patients had significantly higher CRP and IL6 levels than controls. Their F and Nc levels were within normal limits. Systemic inflammation was present in 56 patients, which had similar disease severity and frequency of inhaled steroid use, compared with patients without inflammation. Patients with systemic inflammation had more AE in the previous year; lower inspiratory capacity, greater dyspnea during the six minutes walk test and worse SGRQ and CRQ scores. Conclusions: Low-grade systemic inflammation was found in 56 of 104 ex-smokers with COPD. This group showed a greater degree of lung hyperinflation, dyspnea on exercise and poor quality of life.