緑膿菌性慢性下気道感染症の病態と治療に関する臨床的・基礎的研究

Abstract

The present study was addressed to analyze the clinical features of chronic lower respiratory tract infections (CLRTI) due to Pseudomonas aeruginosa in relation to bacteriological findings as determined by transtracheal aspiration (TTA), and also to evaluate clinically and basically a long-term chemotherapy of erythromycin (EM) or clarithromycin (CAM) against CLRTI. The following results were obtained ; 1. The isolation rate of P. aeruginosa among the total isolates from CLRTI patients by TTA increased year by year. As predisposing factors to exacerbate in CLRTI caused by P. aeruginosa alone, the early colonization by P. aeruginosa in the airway or immunological status of patients was very important. Mucoid P. aeruginosa was more important as a persistent infection in CLRTI than nonmucoid P. aeruginosa. 2. A Long-term treatment of EM benefited patients with CLRTI due to P. aerzaginosa from improvement of purulent sputum, dyspnea on effort, and decreased PaO₂. CAM was able to substitute for EM when EM was not effective for CLRTI deu to P. aeruginosa. 3. EM inhibited biofilm formation in culture of human epithelial cells and P. aeruginosa. In patients with CLRTI, the administration of EM or CAM enhanced the IL-2 producing ability of peripheral blood mononuclear cells (PBMC) and also elevated serum IL-4 levels in the early phase of treatment. Thereafter, the IL-2 producing ability of PBMC gradually decreased and returned to the levels of healthy controls. The above are new findings on the clinical features of incurable CLRTI due to P. aeruginosa, and beneficial aspects of treatment with macrolides.