Certain oxidative and hydrolytic enzymes in the middle ear effusion in serous otitis media

Activities of various oxidative (LDH, MDH) and hydrolytic (LAP, alkaline- and acid phosphatase, and lysozyme) enzymes in serous middle ear effusions (MEE) and serum from patients with serous otitis media were studied. The ratio of enzyme activity between MEE and serum (MEE/serum) was greater than one for all enzymes studied indicating a higher activity of these enzymes in MEE than in serum. These findings are consistent with a hypothesis suggesting the release of enzymes from inflammatory processes in the middle ear cavity. These enzymes presumably originate from 1) enzymes normally present in blood, 2) release of enzymes from inflamed middle ear mucosa, 3) release of enzymes from inflammatory cells present in the effusions.