Bronchial epithelium in humans recently recovering from respiratory infections caused by influenza or mycoplasma.

Sixty three bronchial mucosal biopsies were collected from 12 patients recovering from respiratory infections with influenza virus (n = 8) and Mycoplasma (n = 4). The bronchoscopy was performed within 1-6 wks from the onset of symptoms. Of the 63 biopsies prepared for light microscopy, 27 biopsies from the influenza patients and 10 from the Mycoplasia patients were further analysed at the light and electron microscope level. The epithelium and the underlying stroma was analysed morphometrically and the results were compared to those of 39 biopsies from 27 healthy subjects. A slightly raised bronchial reactivity was noted in two patients. In the influenza patients the epithelial height was greater compared to that of the healthy subjects and subepithelial lymphocytosis was noted. Areas with damaged epithelium, epithelium shedding, and occasionally a thickened basement membrane, considered typical for asthma, occurred in both infected groups, and in the biopsies of the healthy subjects.