Can Helicobacter pylori cause inflammation in the middle ear?

To investigate whether Helicobacter pylori causes inflammation in the normal middle ear and in the middle ear with effusion.

Sixteen adult New Zealand white rabbits were divided into two gropus equally. Group I was representing histamine-induced middle ear inflammation and Group II was representing normal middle ear. While H. pylori was inoculated in the right ears, physiologic saline was inoculated in the left ears of the rabbits in both groups. Results were evaluated clinically, histopathologically and microbiologically. Fisher's exact test was used for statistical analysis.

In Group I, clinical scores of the inflammation in the right ears were higher than the left ears scores at the 7th day. Histopathological scores of the inflammation in the right ears were higher than the left ears scores at the 7th day. Also, H. pylori was isolated in 6 of the 8 right ears of the rabbits. In Group II, while clinical scores of the inflammation in the right ears scores were higher than the left ears scores at the 7th day, histopathological scores were not significantly different between both ears. Also, no H. pylori was isolated in right ears of the rabbits.

Effusion in the middle ear induced by histamine is an appropriate medium for H. pylori reproduction and it also aggravates the inflammation process. In contrary, H. pylori did not cause inflammation in the normal middle ear. We suggest that H. pylori does not play a role in the etiology of otitis media with effusion alone, but it contributes to the inflammation process in the presence of an effusion.