To study allergic and immunologic incidence of secretory otitis media, histamine levels were investigated in 90 cases with middle ear effusion by means of the fluorometric assay.
Histamine concentration in effusions were significantly higher than serum levels.
Statistical analysis indicated that there was no differences between serous and mucoid effusions, nor between children and adults.
Tympanic mucosa from the patients with secretory otitis media was examined under electron microscopy, and mast cells were found in the subepithelial layer in many cases. They often exocytosed their specific granules, indicating active histamine release.
These data suggested that histamine appears more actively released into the tvmpanic cavity rather than a simple transdate from plasma, and it may play an important role in the pathogenesis and the chronicity of secretory otitis media.