Secretory Immunoglobulin A In Suppurative Otitis Media

Abstract

Background: Secretory Ig A constitute a local immunological factor protecting the middle ear against invasion of pathogens and prevention of tissue damage by toxins. The aim of this study was to determine the serum and middle ear secretion(MES) level of Ig A in acute(ASOM) and chronic suppurative otitis media (CSOM) and evaluate the possibility of using Ig A as index of chronicity. Method: Enzyme immunodiffusion technique. Result: The subjects and control were made of 30 males and 22 females, between 6 months and 9 years, mean of 6 years(SD =3.26 ). Paired sera and middle ear secretion (MES) from 37 subjects with suppurative otitis media comprising of 20 CSOM and 17 ASOM and sera of 15 control were analysed. The mean serum levels of Ig A were control group 36mg/dL, ASOM 46.1mg/dL, CSOM 41mg/dL, while the MES levels were ASOM 228.3mg/dL and CSOM 85.4mg/dL. (Table 1). The mean MES : serum ratio were 4.95 for ASOM and 2.1 for CSOM. The ratio of the serum level of control group to ASOM was 1.3 while control to CSOM was 1.14. Multivariate analysis using unpaired t-test to compare the mean revealed significant statistical difference between the MES level of ASOM and CSOM (P= 0.0056) but no significant difference between serum level of ASOM and CSOM(P=0.57), and serum level in control and ASOM (P=0.25). Conclusion: The Ig A level in middle ear secretion was higher in ASOM than CSOM, thus reduced secretion may be associated with chronicity. The monitoring Ig A assay may be useful index of determining likely progression to chronicity, however, further study is still needed to establish this hypothesis.