Osamu Fujioka

Otitis media with effusion following inoculation of Haemophilus influenzae type b endotoxin

SummaryLipopolysaccharide endotoxin (LPS) was extracted from Haemophilus influenzae type b by using Westphals phenol water method. The ears of 40 adult male guinea pigs were subsequently inoculated with 10 μg/ml solutions of LPS by transmeatal injections. Groups of animals were then sacrificed from day 2 to day 24 after the injections to observe the pathological changes produced. Massive serous effusions filled the tympanic bullae on days 2 and 4, after which the amount of fluid present gradually decreased so that it could hardly be seen on day 11. Pathological changes found in the mucosa included marked interstitial edema, dilated capillaries, as well as elevated and thickened epithelium with intracellular edema. These findings gradually subsided by day 24. We believe that the major pathogenetic factors present were due to the transudation and injury of the middle ear epithelium disturbing mucociliary transport activity, with increased secretions participating somewhat in inducing the effusion. We further suggest that H. influenzae endotoxin may play an active role in the clinical development of otitis media with effusion.

Experimentally induced otitis media with effusion following inoculation with the outer cell wall of nontypable Haemophilus influenzae

SummaryPreviously, we extracted lipopolysaccaride endotoxin (LPS) from an axenic culture of Haemophilus influenzae and inoculated it into the middle ears of guinea pigs, inducing temporary serous effusions. In the present study, we tried to clarify whether the immunological mechanism responsible for producing the otitis media following outer cell wall inoculation was persistent. We extracted the outer cell wall from nontypable H. influenzae, using Zollingers method, and inoculated extracts into the middle ears of guinea pigs that had previously received three injections of nonviable H. influenzae in Freunds complete adjuvant. Histological evaluations were performed from day 2 to day 24. Effusions and mucosal changes persisted for a longer time than in the LPS-inoculated model. Hypertrophied mucosae and increased numbers of goblet cells with hypersecretion were visible in the specimens on days 23–24. The condition seemed to show a greater similarity to chronic otitis media with effusion in children than did the LPS-inoculated model. We concluded that both the biological activity of the outer cell wall and immunological mechanisms might induce prolonged otitis media. We speculate that not only single middle ear infection but also general infections and repetitive middle ear infections may contribute to prolonged otitis media.

Evaluation of mastoid air cell system by three-dimensional reconstruction using sagittal tomography of the temporal bone

The mastoid air cell system has been recognized as an important contributor to the pathophysiology of middle ear inflammatory diseases. Various methods of temporal bone imaging have been designed to investigate the correlation between middle ear disease and mastoid pneumatization. In this study, the mastoid air cell system was reconstructed three-dimensionally from sagittal tomographic images of the temporal bone on X-ray films, using a personal computer to evaluate the mastoid pneumatization in a total of 29 patients with chronic otitis media, adhesive otitis media, adhesive-type cholesteatoma, attic cholesteatoma and cholesterol granuloma, and in five normal subjects as controls. Reconstructed three-dimensional images of the mastoid air cell system and its volume were analyzed. The reconstructed images were helpful in recognizing the three-dimensional solid appearance of the mastoid air cell system. The volume of the reconstructed mastoid air cell system was significantly reduced compared with that in the controls in each of the patient groups. Mastoid pneumatization in the patients with adhesive-type cholesteatoma was significantly suppressed compared with that in the adhesive otitis media patients. Interestingly, the adhesive otitis media group showed cell development at the tip of mastoid process, whereas the group of adhesive-type cholesteatoma did not, suggesting a difference in the pathophysiology in the two diseases. We found that three-dimensional reconstruction of the temporal bone using sagittal tomographic images was useful in evaluating the state of mastoid air cell system development in individual cases and in investigating the pathophysiology in middle ear disease.

The immunological role of the outer membrane proteins of non-typableHemophilus influenzae in otitis media with effusion in children

SummarySpecific IgG and IgA antibodies against the outer membrane proteins of non-typableHemophilus influenzae were investigated in otitis media with effusion in children. Amounts of these antibodies were determined in middle ear effusions (MEEs) and in sera by enzyme-linked immunosorbent assay. At the same time the amounts of total IgG and IgA antibodies in MEEs in comparison with those in sera were analyzed by laser nephelometry. The amounts of specific and total IgG and IgA in the MEEs were higher than those in the sera. The MEEs/sera ratios of IgG and IgA antibodies in the children with mucoid effusions were higher than those in the children with serous effusions. The exception involved IgG determined by laser nephelometry. These data support the hypothesis that bacterial infections and the subsequent immune response contribute to the prolongation of otitis media with effusion in children, especially when effusions become mucoid.

Otitis Media with Effusion Following Inoculation of Endotoxin of Haemophilus influenzae Type B

The etiology and pathogenesis of otitis media with effusion (OME) as yet remains to be elucidated. OME was considered a sterile condition until recent reports of isolation of bacteria from the effusion of OME. The incidence of Haemophilus influenzae is high chronic OME cases. Consequently working on the postulation that endotoxin from H. influenzae may play some role in the development of OME, the endotoxin was extracted and inoculated into the tympanic bullae of guinea pigs.

Adherence of Haemophilus infuenzae to Middle Ear Mucosa Injured by Killed H. infuenzae

Repetitive acute otitis media is due to recurrent bacterial infection of middle ear superimposed on chronic otitis media with effusion. Endotoxin, one of the constituents of Haemophilus infuenzae , is present in some cases in the middle ear effusion of otitis media with effusion and has been demonstrated experimentally to damage the middle ear mucosa. The aim of this study was to determine the effect of killed H. infuenzae on the adherence of H. infuenzae and H. parainfuenzae to the middle ear epithelial cells. The numbers of adherent organisms per epithelial cell in ears inoculated previously with killed H. infuenzae or with normal saline (0.9% NaCl) were compared. Prior middle ear inoculation of killed H. infuenzae enhanced the adherence of H. infuenzae to middle ear epithelial cells, but it had little effect on the adherence of H. parainfuenzae . H. infuenzae adhered to middle ear epithelial cells in greater numbers than H. parainfuenzae . Results demonstrate that a middle ear pathogen adheres to middle ear epithelial cells presumably damaged by killed H. infuenzae , whereas a non-pathogen does not. These findings might partly explain the increased susceptibility of an ear with chronic otitis media with effusion to recurrent infection with H. infuenzae .

Cholesteatoma with Hunt's syndrome.

Two cases of cholesteatoma with Hunts syndrome are presented.One patient was a 52-year-old male who complained of left otorrhea, temporalgia and auricular swelling. After admission to our clinic, left facial palsy and vertigo appeared. A diagnosis of left aural cholesteatoma was made, and tympanoplasty was performed. At the same time, the titer of varicella-zoster virus was found to be elevated. The second patient was a 55-year-old female who had received medication for Hunts syndrome three years earlier prior to tympanoplasty for aural cholesteatoma.In general, cases of cholesteatoma with facial palsy should have immediate surgery. In all but a few cases, the facial canal is left intact. However, in Hunts syndrome surgical decompression is performed in those cases in which conservative therapy is ineffective.