Inflammatory cells in the middle ear mucosa in cases of chronic otitis media.

Middle ear mucosal biopsy specimens were taken from 12 patients with chronic otitis media. The specimens from 11 cases contained enough inflammatory cells for a detailed study of the inflammatory cell subtypes in the lamina propria. T lymphocytes, mononuclear phagocytes, and plasma cells were the most frequent cell types except in two patients, in whom most of the inflammatory lymphocytes were B lymphocytes. The relative scarcity of B lymphocytes could be caused by activation and transformation to plasma cells. The close contact between different immunocompetent cells suggests T- and B-cell interactions. However, pseudolymphoid transformation with primary and secondary lymphatic follicles was observed in only one patient. The relative scarcity of granulocytes in the submucosal infiltrate could be caused by the movement of these cells through the epithelium into the discharge.