[Pathomorphological characteristics of unstable bronchial asthma (brittle phenotype)].

AIM: To ascertain morphological features of severe uncontrolled bronchial asthma (BA) of brittle phenotype.

MATERIAL AND

METHODS

Standard bronchofibroscopy was made in 10 patients with severe BA (brittle phenotype) and 9 patients with moderate BA. Cell composition of bronchial lavage and morphological indices of bronchial mucosa biopsies were studied.

RESULTS

Patients with brittle BA had low total cytosis of lavage fluid compared to patients with moderate BA patients (1.73 +/- 0.10 and 2.84 +/- 0.21 x 10(6) in 1 ml, respectively, p = 0.001). Bronchobiopsy samples from patients with brittle BA were characterized by reduced cubic density of tegmental epithelium, ciliary and goblet epithelyocytes, height of epithelial layer and relative gland volume, increased thickness of basal membrane (18. 77 +/- 2.74 mcm), relative volume of connective tissue, hyperplasia of smooth muscle cells in the proper mucous plate. Infiltrate of bronchial mucosa in brittle BA contained a predominant amount of histiomacrophagal elements (65.80 +/- 3.83 in 1 mm2) and lymphocytes (52.94 +/- 4.38 in 1 mm2), moderate count of easinophils and neutrophils (15.35 +/- 2.13 and 19.04 +/- 2.23 in 1 mm2, respectively).

CONCLUSION

Patients with severe brittle BA had atrophic alterations, inflammatory mucosal infiltration, marked bronchial remodeling in spite of therapy with high doses of inhalatory corticosteroids.