Secretory antibodies specific to Streptococcus pneumoniae, Haemophilus influenzae and Branhamella catarrhalis in middle ear effusion during acute otitis media.

The occurrence of specific secretory antibodies against the type-specific capsular polysaccharide of Streptococcus pneumoniae (Pn) and against the whole cell antigen of Haemophilus influenzae (Hi) and Branhamella catarrhalis (Br) were measured by the ELISA method in 211 middle ear effusion (MEE) samples of 85 children with acute otitis media (AOM) during the course of the disease. Antibodies against at least one of those bacteria were detected at the initial visit in 33.6% of the ears and later in 20%. All in all, such antibodies could be found in 50% of the ears during the follow-up. Pneumococcal secretory antibodies were found in 5 out of 116 ears only, anti-Hi antibodies in 52 and anti-Br antibodies in 42 ears. The specific secretory antibodies were detected against all these bacteria regardless of the bacterial etiology of the AOM attack in question. The AOM attack was prolonged more often if such antibodies were not found in the MEE sample taken at the initial visit. The appearance of such antibodies during the disease seemed to imply termination of the AOM episode in question. The conclusions of this study are that during an AOM attack a local production of antibodies in middle ear against the three most common bacteria. Pn, Hi and/or Br, causing AOM may be induced. The appearance of such antibodies in MEE seems to be beneficial for the resolution of AOM.