CHANGES IN GOBLET CELL-DENSITY IN RAT MIDDLE-EAR MUCOSA IN ACUTE OTITIS-MEDIA

This study was undertaken to determine quantitative histologic changes after a single episode of acute suppurative otitis media in the rat m iddle ear mucosa, with special reference to global cell density, and t o determine the persistency of these changes. Drum vascularization, pu rulent effusion, mucosal thickness, bone, and subepithelial gland form ation were assessed. Twenty-five rats were inoculated with viable pneu mococci type 3 through the right, bony middle ear bulla. The left bull a served as control. At days 4, 8, 16, 90, and 180 after inoculation, five rats were sacrificed on each occasion; the bullae were removed, o pened, and divided in two halves, which were stained according to the periodic acid-Schiff (PAS)-alcian blue method. The stained mucosa was dissected from the bone and placed in an anise oil-colophonium chamber , for determination of interindividual median density and range of gob let cells by light microscopy. Counting was performed in 24 well-defin ed localities, covering the entire bulla mucosa and the drum. Areas no rmally containing goblet cells were extended. Goblet cell density was significantly (Mann-Whitney, p < .05) increased in almost all localiti es, reaching a maximum at day 16, whereafter the mucosa normalized. Al l changes quantitated, except drum vascularization and purulent effusi on, were persisting at day 180. Cobblestone appearance of the epitheli al surface and polypous mucosal prominences were found. Mucosal thicke ning was prominent in areas covered with flat epithelium, less so in o ther areas. Local differences in the degree of increased mucosal thick ness were preventing intrinsic tubal occlusion. Enhanced secretory abi lity of the middle ear mucosa was persisting 6 months after a single e pisode of acute suppurative otitis media, perhaps predisposing secreto ry otitis media.