ABSTRACT
Introducción: En algunos pacientes asmáticos la obstrucción de las vías aéreas no puede ser revertida por tratamiento broncodilatador y/o corticosteroideo. Esta obstrucción irreversible se ha atribuido a la remodelación de las vías aéreas, pero otros mecanismos, como el taponamiento mucoso, no se han explorado. Objetivo: Evaluar si la rhDNasa, enzima ampliamente usada para fluidificar el moco respiratorio en la fibrosis quística, mejora las variables espirométricas y la calidad de vida de pacientes con asma grave. Pacientes y métodos: Diez pacientes adultos (6 mujeres) con asma grave, dependientes de corticosteroides, recibieron nebulizaciones diarias de 2.5 mg de rhDNasa durante 14-28 días. Se realizaron espirometrías por lo menos cada semana, evaluando la capacidad vital forzada (FVC), el volumen espiratorio forzado al primer segundo (FEV1, la relación FEV1/ FVC y el flujo espiratorio máximo (PEF). Los cambios espirométricos se evaluaron mediante análisis de regresión. Se aplicó un cuestionario de calidad de vida antes y al final del tratamiento. Resultados: Las variables espirométricas no cambiaron en la mayoría de los pacientes. Sin embargo, al menos un paciente tuvo mejoría de la función pulmonar, de acuerdo con las pendientes ascendentes estadísticamente significativas en la FVC, el FEV1 y la relación FEV1/FVC. Aunque otros sujetos también tuvieron cambios ascendentes (2 pacientes) o descendentes (2 pacientes) de las pendientes, éstos sólo ocurrieron en una de las variables espirométricas. Como grupo, los pacientes mostraron tendencia a la mejoría en la calidad de vida. Conclusiones: Aunque la rhDNasa no modifica la obstrucción bronquial irreversible en la gran mayoría de los pacientes con asma grave, una pequeña proporción de ellos podría obtener algún efecto benéfico.
Background: In some asthma patients airway obstruction can not be reverted by bronchodilator and/ or corticosteroid treatment. This irreversible obstruction has been attributed to the remodeling process of airways, but other mechanisms such as mucus plugging have not been explored. Objective: To evaluate if rhDNase, an enzyme extensively used to fluidize the mucus in cystic fibrosis, improves spirometric variables and quality of life of asthmatic patients. Patients and methods: Ten adult patients (6 females) with severe corticosteroid-dependent asthma received daily nebulizations of 2.5 mg rhDNase during 14-28 days. Spirometries were performed at least at weekly intervals to evaluate the forced vital capacity (FVC), forced expiratory flow at the first second (FEV1, the FEV1/FVC ratio and peak expiratory flow (PEF). Changes in spirometric variables were assessed by regression analysis. An asthma quality of life questionnaire was applied before and at the end of treatment. Results: Spirometric variables did not change in most patients. However, pulmonary function improved in one patient, according to the statistically significant ascending slopes in FVC, FEV1 and FEV1/FVC. Although other subjects also had ascending (2 patients) or descending (2 patients) slopes, these changes only occurred in one spirometric variable. As a group, there was a trend for improvement in quality of life. Conclusions: Although rhDNase does not modify the irreversible bronchial obstruction in most patients with severe asthma, a small proportion of them might obtain some beneficial effect.
ABSTRACT
Abnomalities in the production and transport of airway secretions play an important role in the pathophysiology of asthma. Segmental atelectasis as a complication of asthma, is relatively common in children. On the other hand, massive atelectasis such as the collapse of one lung is a very rare occurence. We report a seven-year-old male asthmatic patient with right lung collapse caused by mucoid impaction. Fourteen months before admission, the patient experiened bronchopneumonia with left unilateral lung collapse due to mucus plugging and recovered by bronchoscopic removal. The clinical findings, chest X-ray and chest CT suggested the collapse of the right lung was caused by mucus plugging. Fiberoptic bronchoscopy revealed the obstruction of the right main bronchus due to thick mucoid impaction. The histologic finding of mucoid material removed by brochoscopy showed only eosinophil clusters. In addition to fibroptic broncoscopic removal of mucoid secretions, hydration, chest physiotherapy, brochodilators and steroids, the patient received tracheostomy because of difficulty in sputum expectoration, poor improvement of clinical symptoms and chest X-ray findings, with rapid improvements. This case showed that early aspiration of bronchial mucoid secretions by bronchoscopy and tracheostomy was very critical, without waiting for a further deterioration of respiratory function.