Bronquiectasias: ¿no es más una enfermedad huérfana? / Bronchiectasis: is it no longer considered an orphan disease?

Bronchiectasis, so far considered an orphan disease, currently is diagnosed with a higher frequency due to several reasons such as renewed awareness of the disease, better diagnosis including imagenology, the development of patients registries, as well as a higher number of clinical research studies. The pathological basis of bronchiectasis is widely variable. Also the clinical expression is variable, from absence of symptoms in some patients up to chronic sputum production in others. Furthermore, a group of patients often develop recurrent exacerbations. Despite the etiologies of bronchiectasis are diverse, the main etiology is previous pulmonary infection. On the other hand, bronchiectasis could also be the expression of diverse systemic diseases. Even around one quarter of patients the etiology would not be established. The development of large registries of patients has allowed the building of classifications systems with accurate prognostic criteria. Chronic infection is the most relevant issue in bronchiectasis. Infection with P. aeruginosa has been associated with poor prognosis and their eradication must be attempted always. Effective secretions drainage techniques, oral and nebulized antibiotics, as well as mucolytic therapy are the mainstay of treatment in bronchiectasis.

Las bronquiectasias, consideradas hasta un tiempo atrás una enfermedad huérfana, se diagnostican actualmente con mayor frecuencia debido a un renovado interés en esta patología, a una mejoría de técnicas de diagnóstico, existencia de mejores registros, acceso a mejores imágenes y aumento de los estudios clínicos. El sustrato anátomo-patológico es notablemente variable, al igual que la expresión clínica, que va desde la ausencia de síntomas hasta la presencia de broncorrea crónica. A su vez, un grupo de pacientes tiende a presentar exacerbaciones frecuentes. Las etiologías de las bronquiectasias son múltiples, siendo la más frecuente la existencia de infecciones pulmonares previas. También pueden formar parte de enfermedades crónicas sistémicas. Sin embargo, en 25% de los casos no es posible identificar la etiología. El desarrollo de registros de pacientes ha permitido construir modelos de clasificación de gravedad, lo que hace posible establecer criterios pronósticos. La infección crónica es un hecho frecuente en bronquiectasias y la presencia de P aeruginosa confiere mal pronóstico a la enfermedad. La erradicación de Pseudomonas debe ser intentada siempre en estos pacientes. El uso de técnicas de drenaje, los antibióticos orales y nebulizados y las terapias mucolíticas constituyen los pilares centrales en el manejo de la enfermedad.

Estudio multicéntrico de factores pronósticos en adultos hospitalizados por neumonía adquirida en la comunidad / Prognostic factors and outcome of community-acquired pneumonia in hospitalized adult patients

Background: Severity assessment of community-acquired pneumonia (CAP) patients allows the clinician to decide the place of management and guide empirical antimicrobial treatment. Aim: To assess admission prognostic factors and outcome of CAP in immunocompetent adult patients hospitalized in 21 medical centers in Chile. Material and methods: Prospective evaluation of non immunocompromised adults with CAP admitted to 21 Chilean hospitals between July and August, 1999. All patients were assessed on admission and followed until discharge or death. Results: During the study period, 1,194 patients (aged 68±17 years, 573 males) were evaluated. Seventy two percent had an underlying disease (especially chronic cardiovascular, neurological, respiratory diseases and diabetes mellitus), and 90 percent were treated with ß-lactamic agents (especially a third generation cephalosporin or penicillin). Mean hospital length of stay was 11±9 days, 10 percent were admitted to Intermediate Care or Intensive Care Units (ICU), 6 percent were mechanically ventilated and in-hospital mortality was 15.7 percent. Admission prognostic factors associated with hospital mortality were: advanced age, male gender, presence of comorbidity (chronic cardiovascular, renal, neurological and hepatic disease), undernutrition, suspicion of aspiration, altered mental status, low blood pressure, tachypnea, absence of fever, high blood urea nitrogen, multilobar radiographic pulmonary infiltrates, high risk categories from Chilean Respiratory Diseases Society Consensus, admission to Intermediate Care Units or ICU, and mechanical ventilation. In the multivariate analysis, prognostic factors associated with high hospital mortality were: mental confusion, high blood urea nitrogen, multilobar pneumonia, presence of comorbidity and absence of fever on admission. Conclusions: These results validate in Chile, findings from foreign studies.

Limitación crónica al flujo aéreo en pacientes con secuelas de tuberculosis pulmonar: Caracterización y comparación con EPOC / Chronic airways obstruction in patients with tuberculosis sequelae: a comparison with EPOC

Chronic airway obstruction (CAO) resulting from tuberculosis (TB) sequelae (CAO-TB) is a frequent condition in our population. However the information in the medical literature is scarce. The management of these patients usually follows guidelines for other illnesses such as chronic obstructive pulmonary disease (COPD) or asthma. To better characterize CAO-TB, 25 patients with this condition that never smoked nor were diagnosed having asthma, were studied by means of spirometry, arterial blood gases and 6-minute walk test. Furthermore, they were compared with 12 COPD patients with similar FEV1 values. CAO-TB patients had history of tuberculosis 35 ± 11 years earlier, and all of them presented with lung scarring in one or both upper lobes. They were younger than COPD (58 ± 11 vs 69 ± 6 y.o.; p = 0.001) and females predominated over males (20/5 vs 2/10; p = 0.001). The FEV1/FVC ratio pre- and post-bronchodilator were higher in CAO-TB than in COPD patients (67 percent ± 12 vs 54 percent ± 9 pre; p = 0.001; 65 percent ± 14 vs 51 percent ± 7; p = 0.003 post, respectively). There were no differences in the remaining spirometric indices nor in arterial blood gases. The 6-min distance walked was comparable in both groups: 343 m (69 percent) in CAO-TB and 361 m (76 percent) in COPD. There were no differences in the oxygen saturation nor in heart rate neither at the beginning nor at the end of the 6-min walk test. However, CAO-TB patients had a higher respiratory rate at the beginning (22.7 ± 4.7 vs 19.8 ± 3.1 breath/min; p = 0.05) and at the end of the walk test (27.3 ± 6.7 vs 21.9 ± 3.3; p = 0.01) than COPD patients; although the Borg dyspnoea score was not different (1 ± 0,7 vs 1 ± 0.5 initial, 3 ± 1.5 vs 2.5 ± 0.8 final). Furthermore, a significant linear correlation between respiratory rate and Borg score was found both at the beginning (r = 0.747; p < 0.001) and at the end (r = 0.507; p = 0.01) of the walk test. In conclusion, CAO-TB patients are functionally comparable to COPD patients, although they have higher respiratory rate and develop more dyspnoea because of their added restrictive impairment. In addition to spirometry, tests for assessment of dyspnoea such as 6-minute walk test must be considered, to evaluate the response to treatment in CAO-TB patients.

La limitación crónica al flujo aéreo (LCFA) secundaria a secuelas de tuberculosis (LCFA-TB) es relativamente frecuente en nuestro medio, pero la información sobre esta condición en la literatura es escasa. El manejo terapéutico de estos enfermos suele seguir las guías de otras entidades como la Enfermedad Pulmonar Obstructiva Crónica (EPOC) y el Asma Bronquial. Con el objetivo de caracterizar la LCFA-TB, 25 enfermos con esta condición, que nunca fumaron ni tuvieron asma, fueron estudiados mediante espirometría, gasometría arterial y prueba de caminata de 6 minutos. Los pacientes LCFA-TB fueron comparados con 12 pacientes EPOC que tenían un grado similar de obstrucción. Los enfermos con LCFA-TB habían presentado tuberculosis 35 ± 11 años antes y tenían lesiones fibrosas con retracción en uno o ambos lóbulos superiores. Eran más jóvenes que los pacientes con EPOC (58 ± 11 vs 69 ± 6 años; p = 0,001) y predominaban las mujeres sobre los hombres (20/5 vs 2/10; p = 0,001). La relación VEF1/CVF basal fue más elevada en los pacientes con LCFA-TB que en los con EPOC (67 por ciento ± 12 vs 54 por ciento ± 9; p = 0,001) al igual que la relación VEF1/CVF posterior a broncodilatador (65 por ciento ± 14 vs 51 por ciento ± 7; p = 0,003). No hubo diferencias en los demás índices espirométricos ni en los gases arteriales. La distancia recorrida en 6 minutos fue similar en ambos grupos de pacientes: 343 m (69 por ciento) en LCFA-TB y 361 m (76 por ciento) en EPOC. No hubo diferencias en la oximetría ni en la frecuencia cardíaca inicial ni final. En cambio, los pacientes con LCFA-TB presentaron una frecuencia respiratoria (FR) más elevada que los pacientes con EPOC, tanto al comienzo (22,7 ± 4,7 vs 19,8 ± 3,1; p = 0,05) como al final de la prueba (27,3 ± 6,7 vs 21,9 ± 3,3; p = 0,01). Aunque no hubo diferencias en el grado de disnea (escala de Borg: 1 ±0,7 vs 1 ± 0,5 inicial, 3 ± 1,5 vs 2,5 ± 0,8 final). Además, existió una correlación significativa entre la FR y los puntos de la escala de Borg al inicio de la prueba (r = 0,747; p < 0,001) y al final de ésta (r = 0,507; p = 0,01). En conclusión, los pacientes con LCFA-TB tienen un comportamiento funcional parecido a los pacientes con EPOC, aunque por el componente restrictivo de su limitación ventilatoria presentan más polipnea y tienden a desarrollar más disnea con el ejercicio. La valoración de la respuesta al tratamiento en estos enfermos debiera considerar, además de la espirometría, pruebas de evaluación de disnea como la distancia recorrida en seis minutos.

[Prognostic factors and outcome of community-acquired pneumonia in hospitalized adult patients]. / Estudio multicéntrico de factores pronósticos en adultos hospitalizados por neumonía adquirida en la comunidad.

BACKGROUND: Severity assessment of community-acquired pneumonia (CAP) patients allows the clinician to decide the place of management and guide empirical antimicrobial treatment. AIM: To assess admission prognostic factors and outcome of CAP in immunocompetent adult patients hospitalized in 21 medical centers in Chile. MATERIAL AND METHODS: Prospective evaluation of non immunocompromised adults with CAP admitted to 21 Chilean hospitals between July and August, 1999. All patients were assessed on admission and followed until discharge or death. RESULTS: During the study period, 1,194 patients (aged 68+/-17 years, 573 males) were evaluated. Seventy two percent had an underlying disease (especially chronic cardiovascular, neurological, respiratory diseases and diabetes mellitus), and 90% were treated with beta-lactamic agents (especially a third generation cephalosporin or penicillin). Mean hospital length of stay was 11+/-9 days, 10% were admitted to Intermediate Care or Intensive Care Units (ICU), 6% were mechanically ventilated and in-hospital mortality was 15.7%. Admission prognostic factors associated with hospital mortality were: advanced age, male gender, presence of comorbidity (chronic cardiovascular, renal, neurological and hepatic disease), undernutrition, suspicion of aspiration, altered mental status, low blood pressure, tachypnea, absence of fever, high blood urea nitrogen, multilobar radiographic pulmonary infiltrates, high risk categories from Chilean Respiratory Diseases Society Consensus, admission to Intermediate Care Units or ICU, and mechanical ventilation. In the multivariate analysis, prognostic factors associated with high hospital mortality were: mental confusion, high blood urea nitrogen, multilobar pneumonia, presence of comorbidity and absence of fever on admission. CONCLUSIONS: These results validate in Chile, findings from foreign studies.

[Microbiologic diagnosis of community-acquired pneumonia in adults]. / Diagnóstico microbiológico de la neumonía del adulto adquirida en la comunidad.

Microbiological analysis allows us to identify the etiology of pneumonia and its in vitro susceptibility pattern. Antibiotic treatment directed against a known pathogen enables us to narrow antibacterial spectrum of action, and to reduce costs, drug adverse effects risk and antibiotic resistance. However it is unnecessary to perform extended microbiological studies in all patients with community acquired pneumonia (CAP). Etiological studies must be based in pneumonia severity, epidemiological risk factors and clinical response to empirical treatment. Routine microbiological analysis for ambulatory patients is not recommended. In patients with persistent cough and worsening in their general conditions, a sputum sample must be obtained to perform an acid-fast smear and Mycobacterium culture. The risk of complications and death of patients hospitalized with CAP justifies basic microbiological exploration (sputum Gram staining and culture, blood cultures, pleural fluid culture) intending to obtain a more accurate etiology of pulmonary infection and to guide specific antibiotic treatment. Paired serum samples obtained to document atypical pathogen infections (Mycoplasma pneumoniae, Chlamydia pneumoniae) and urine sample to detect Legionella pneumophila antigenuria are recommended in all CAP severely ill patients that are admitted to ICU, in those not responding to betalactamic drug treatment and in selected patients with specific epidemiological risks. A microbiological study would be useful in management of patients with severe CAP pneumonia outbreaks with clinical-epidemiological particular characteristics, and in-patients with empirical antimicrobial treatment failure.

Diagnóstico microbiológico de la neumonía del adulto adquirida en la comunidad / Of community-acquired pneumonia in adults microbiologic diagnosis

Microbiological analysis allows us to identify the etiology of pneumonia and its in vitro susceptibility pattern. Antibiotic treatment directed against a known pathogen enables us to narrow antibacterial spectrum of action, and to reduce costs, drug adverse effects risk and antibiotic resistance. However it is unnecessary to perform extended microbiological studies in all patients with community acquired pneumonia (CAP). Etiological studies must be based in pneumonia severity, epidemiological risk factors and clinical response to empirical treatment. Routine microbiological analysis for ambulatory patients is not recommended. In patients with persistent cough and worsening in their general conditions, a sputum sample must be obtained to perform an acid-fast smear and Mycobacterium culture. The risk of complications and death of patients hospitalized with CAP justifies basic microbiological exploration (sputum Gram staining and culture, blood cultures, pleural fluid culture) intending to obtain a more accurate etiology of pulmonary infection and to guide specific antibiotic treatment. Paired serum samples obtained to document atypical pathogen infections (Mycoplasma pneumoniae, Chlamydia pneumoniae) and urine sample to detect Legionella pneumophila antigenuria are recommended in all CAP severely ill patients that are admitted to ICU, in those not responding to betalactamic drug treatment and in selected patients with specific epidemiological risks. A microbiological study would be useful in management of patients with severe CAP pneumonia outbreaks with clinical-epidemiological particular characteristics, and in-patients with empirical antimicrobial treatment failure.

Los exámenes microbiológicos permiten identificar el agente causal de la neumonía y su patrón de sensibilidad a antimicrobianos. El tratamiento anti infeccioso dirigido contra un patógeno conocido permite reducir el espectro de acción de los fármacos, los costos, el riesgo de reacciones adversas y de la resistencia antimicrobiana. Sin embargo, no es necesario realizar estudios microbiológicos extensos a todos los pacientes con neumonía adquirida en la comunidad (NAC). Los estudios deben estar guiados por la gravedad de la neumonía, los factores de riesgo epidemiológico y la respuesta al tratamiento empírico. No se recomienda realizar investigaciones microbiológicas rutinarias en los pacientes manejados en el medio ambulatorio. En pacientes con tos persistente y compromiso de su estado general, se debe obtener muestras de expectoración para baciloscopia y cultivo de Koch. El riesgo de complicaciones y muerte de los enfermos hospitalizados por NAC justifica la realización de exámenes microbiológicos básicos (tinción de Gram y cultivo de expectoración, hemocultivos, cultivo de líquido pleural) que intentarán precisar el agente causal de la infección pulmonar y orientar el tratamiento antimicrobiano específico. Se recomienda obtener muestras de suero pareadas para la pesquisa de patógenos atípicos (Mycoplasma pneumoniae, Chlamydia pneumoniae) y una muestra de orina para la detección de Legionella pneumophila en todos los pacientes con NAC grave admitidos a la UCI, en aquellos que no responden a agentes b-lactámicos y en pacientes seleccionados con riesgo epidemiológico específico. El estudio microbiológico podría ser útil en el manejo de pacientes con NAC grave, brotes de neumonía con características clínico-epidemiológicas particulares, y en pacientes con fracaso del tratamiento antimicrobiano empírico.

Reglas de predicción en neumonía adquirida en la comunidad / Prediction rules in community acquired pneumonia

The determination of site of care is an essential decision in the management of patients with community-acquired pneumonia (CAP). Patients with mild to moderate CAP may be safely treated at home. Instead, those patients with severe pneumonia must be hospitalized to assure an effective treatment. Severity of CAP is associated with mortality that depends both on the patient's frailty and the intensity of lung inflammation. Because there is no single predictor factor to assess prognosis, diverse prediction rules have been developed to establish severity of CAP and guide the decision of site of care. In our country a new prediction rule, derived from hospitalized patents that incorporate simple clinical variables has been developed. However, this rule requires to be validated in the ambulatory setting before its wide spread use is suggested. Prediction rules are objective and relatively accurate models to assess prognosis that may aid clinicians to evaluate patient's risks and to improve hospitalization decisions. Nevertheless, although the prediction rules may guide the initial management of patients with CAP, they are not intended to replace the clinical judgment, which remains as the art of medicine.

Infecciones bacterianas en la cirrosis hepática / Bacterial infections in hepatic cirrhosis

The aim of this work was to study the prevalence of bacterial infections in hospitalized patients with liver cirrhosis and to compare clinical, bacteriological and evolution features of patients with (group 1) and without bacterial infection (group 2). 132 hospitalized patients with liver cirrhosis were prospectively studied and 61 episodes of bacterial infections were diagnosed in 52 (27 spontaneous bacterial peritonitis (44.3 per cent) 16 urinary tract infections (26.2 per cent), 10 pneumonias (16.4 per cent), 3 spontaneous bacteremias (4.9 per cent) and 5 miscellaneous infections (8.2 per cent)). 26 per cent of infections were nosocomial. Child-Pugh score was 12 ñ 2 in group 1 vs 10 ñ 2 in group 2 (p=0.047). 65 per cent of identified microorganisms were gram negative and 61.5 per cent of these were E. coli. Hospital mortality of group 1 was 29 per cent and that of group 2 was 9 per cent (p=0.002). It is concluded that there is a high prevalence of bacterial infections in hospitalized cirrhotic patients, that is associated to a high mortality

Cateterización de venas centrales / Central venous catheterization

La cateterización venosa central está indicada cuando no es posible canular venas periféricas, hay necesidad de infundir soluciones irritantes o nutrición parenteral, o se requiere monitorización hemodinámica. La vena basílica permite una fácil punción pero es difícil llegar al tórax, y las tasas de infección y de trombosis son altas. La vena subclavia es fácil de puncionar, pero presenta riesgo de neumotórax y de punción arterial. La vena yugular interna puede ser puncionada en su trayecto bajo el músculo estemocleidomastoídeo, y aunque el riego de neumotórax es mínimo, el de punción arterial es mayor. La vena yugular externa es la vía de elección en pacientes con coagulopatías, pero resulta difícil introducir un catéter hasta el tórax. La vena femoral es la vía de elección en resucitación cardiopulmonar, aunque presenta alta tasa de trombosis. Las complicaciones de la cateterización venosa deben ser reconocidas oportunamente. La técnica de Seldinger es preferible para minimizar la hemorragia en el sitio de inserción. La embolia área se previene con un adecuado manejo de las presiones intratorácicas. El neumotórax y la mal posición del catéter deben ser buscados sitemáticamente mediante radiología. La infección generalmente refleja diserminación de gérmenes a partir de otros focos y en la mayoría de los casos basta recambiar el catéter sobre una guía metálica