Complement anaphylatoxins activity in middle ear effusion

There are various theories on the causes of otitis media with effusion. The exact pathogenesis, however, still remains unknown, while the causes have been so far elucidated and studied by many researchers. This disease occurs frequently in children, showing an increasing trend, often causes subsequent deafness, and its treatment takes a long time causing social hardships. Therefore it is urgent to elucidate the pathogenesis of this disease. In this study the C3a and C5a fragments of complements from middle ear fluids, most closely related to the inflammatory reaction, were measured. The subjects were patients with otitis media with effusion consisting of 5 children and 9 adults. All cases showed retraction in the tympanic membrane findings, B type in the tympanogram classification, and serous type in the properties of middle ear fluids. CRP, alpha-1, alpha-2, beta-, gamma-globulin, neutrocytes, and lymphocytes in serum were normal when examined, and C3, C4, C3a, C5a, and CH50 were normal as well. Extremely high values of C3a and C5a in middle ear fluids were observed. The values of C3a were 18,000 ng/ml at maximum, 5,800 ng/ml at minimum, and 9,293 ng/ml on average. The values of C5a were 86, 20, and 55 ng/ml, respectively. No difference between childhood and adult cases was observed, in spite of differences in the underlying diseases among them. The above results revealed that an extremely intensive inflammatory reaction may take place in the middle ear, and that anaphylatoxin might play an important role as a delayed factor in otitis media with effusion.