[Effect of glucocorticoids in chronic dyspneic asthma: histological and immunohistochemical study of the bronchial mucosa].

This prospective study was done in 8 patients with chronic asthma, hospitalised for an exacerbation of their illness without any evidence of airway infection. The intention was to measure both qualitatively and quantitatively the impact of high dosage glucocorticoids on the inflammatory changes of the bronchial mucus in such patients. Biopsies of the proximal bronchi by fibreoscopy were taken before and after 6 to 9 days of Prednisolone (0.5-0.75 mg/kg per day), this treatment led to a relative rise in the FEV1 (VEMS) of at least 15%. These biopsies were fixed in Bouin and Paraffin, and the sections simultaneously processed for qualitative identification (histochemical and immuno-peroxidasic) of cells infiltrating the bronchial mucosa and for a count of these cells in a pre-determined sub-epithelial zone. It was noted: In all patients at the entry to the study: an essentially lympho-monocytic cellular infiltrate of the bronchial mucosa, a virtual absence of neutrophils, and various abnormalities of the surface epithelium. After 6 to 9 days of steroids there was a persistence of epithelial lesions and in 6 out of 8 patients a statistically significant fall in the density of the inflammatory infiltrate. In 75% patients suffering from exacerbations of chronic asthma, the improvement in the ventilatory function with dosage corticotherapy was accompanied by a fall in the level of inflammatory infiltrate in the proximal bronchi.