Estudi de la població bacteriana endobronquial en la malaltia pulmonar obstructiva crònica. Aplicació del raspall protegit

Abstract

Endobronchial bacteria obtained by sputum cultures in patients with chronic obstructive pulmonary disease (COPD) are often contaminated by oropharyngeal flora. Some alternatives techniques have been explored, like transtracheal aspiration or flexible bronchoscopic techniques like the protected specimen brush (PSB), though both were initially designed for the diagnosis of pneumonia. We have performed two studies based on the PSB that were published afterwards: #1. Monsó, Rosell, Bonet et al; Risk factors for lower bacterial colonization in chronic bronchitis, en J Eur Respir 1999; 13:338-92 and; #2. Monsó, Ruiz, Rosell et al, Bacterial infection in chronic obstructive pulmonary disease. A study of stable and exacerbated outpatients using the protected specimen brush, en Am J Resp Crit Care Med 1995; 152:1316-20. In the first study the risk factors for bacterial colonization were described in 41 stable patients with chronic bronchitis and mild to moderate COPD (FEV1 74%, DE 23%). Based on a logistic regression model, smoking was detected as the most important factor with an OD of 9,8 (IC 95: 1,1 a 83,2). In a subgroup of 18 patients, a second PSB was performed, showing a qualitative agreement of 72.2% and a quantitative agreement of 47.4%. In the second study, a PSB was performed in two similar groups of COPD patients, one in stable situation and the other in an acute exacerbation (FEV1 in stable patients 51%, DE 23% and in exacerbation : 43%,DE 14). The microbiological results show positive cultures in the 25% of stable patients and 51% in the exacerbated group; moreover, bacterial load is as well different: only 5% of stable patients have * 104 colony forming units/ml, while in the exacerbated situation there are 24%. Bacteria isolated in the stable situation were: Haemophilus influenzae 60%, Streptoccocus pneumoniae 30%, Moraxella catarrhalis 10%, Staphiloccocus aureus 10%, Pseudomonas aeruginosa 10% and Acinetobacter spp 10%; while in the exacerbated situation: Haemophilus influenzae 58%, Streptoccocus pneumoniae 17%, Moraxella catarrhalis 12%, Pseudomonas aeruginosa 12%, a globally similar profile. From both studies it can be concluded that smoking is a risk factor for bacterial colonization in COPD patients, that it affects the 25% of the studied group and that during the exacerbation situation, the percentage is nearly duplicated as well as a significant increment of the bacterial load is detected. The bacterial profile is nearly the same, which indicates a possible overgrowth of the preexisting bacterial population.

Date of Award	24 Mar 2000
Original language	Undefined/Unknown
Supervisor	Eduard Monso Molas (Director) & Josep Morera Prat (Director)