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Background: Biofilms are communities of bacteria embedded in a self-produced glycocalyx matrix. Adenoids have been shown to harbor bacterial biofilms. Aim/objectives: To compare the prevalence of biofilms in adenoid of children with chronic otitis media (COM) (group1) versus a control group without any COM (group 2) having adenoids removed because of hypertrophy., Material and Methods: One hundred and three children were prospectively enrolled in this case-control study, group 1 (n = 52) and group 2 (n = 51). The main outcome measurement was the prevalence of biofilm in adenoidectomy specimens analyzed using confocal laser scanning microscopy. Children in group 1 who had middle ear (ME) effusion and requiring the insertion of a tympanostomy tube underwent biopsy of the ME mucosa and effusion sampling., Results: Biofilms were found in adenoids' specimens of both groups and in the ME biopsy and effusion. The biofilm prevalence in adenoids was 63.5% (33/52) in group 1 and 47.1% (24/51) in group 2. Day nursery and previous antibiotics intake were significantly more frequent in group 1 than in group 2., Conclusions and Significance: This case-control study demonstrates that adenoid tissue in children with COM contains more mucosal biofilms than adenoid tissue removed for hypertrophy. Biofilm was seen in ME biopsies and effusion.

Moraxella (Branhaomella) catarrhalis is frequently present in the nasopharyngeal microflora of small children, especially during episodes of acute otitis media . By means of ribotyping (restriction endonuclease analysis of chromosomal DNA combined with rRNA probing), we studied the genetic heterogeneity of 78 cultures of M. catarrhalis obtained from different localities in the nasopharynx of nine young children with secretory otitis media. Using HindIII and PstI as endonucleases, five different ribotypes were recognized, representing at least five different genotypes of M. catarrhalis. The distribution of these types was found to be almost identical to the distribution among 16 M. catarrhalis strains cultured from middle ear exudates of 16 children with acute otitis media. Ribotype HAPA was found in two-thirds of all the cultures investigated, and 44% of the children harboured more than one ribotype in the nasopharynx at the same time. The vast majority of the nasopharyngeal M. catarrhalis cultures were beta-lactamase positive. One child had both a HAPA ribotype, beta-lactamase-negative strain in the nasopharyngeal secretions, and HAPA ribotype, beta-lactamase-positive strains at the entrance of the eustachian tube, the nasopharyngeal tonsils, the folds of the nasopharyngeal tonsils and the oropharynx. All except one of the M. catarrhalis strains cultured from middle ear exudates were beta-lactamase positive.

There is disagreement on the role of bacteria in the genesis and maintenance of chronic secretory otitis media (CSOM). Extensive studies from other countries report up to 40% of middle ear cultures with bacterial growth. For the present study, material was collected from 94 ears of children with both clinical and tympanometric diagnoses of CSOM. The samples were sent for bacteriological analysis, in there it was stained according to Gram's method and put into growing media: MacConkey (for gram-negative bacteria) and blood agar (for gram-positive bacteria) for 24 h, at 37 degrees C. If germs were identified by Gram's method, antibiograms would be carried out as well, with the Mueller Hington medium. No cultures were made for anaerobes. Only one ear had grown bacteria (Staphylococcus epidermidis), which was deemed contamination. No other ear studied bore bacteria. The possible causes for this disagreement between our study and the literature are discussed.

Known numbers (CFU/ml) of middle ear pathogens (S. pneumoniae, H. influenzae, M. catarrhalis, S. aureus and beta-haemolytic streptococci group A) and non-pathogens (alpha-haemolytic S. mitis) were inoculated into one end of a micropipet containing a 35 mm long pillar of culture-negative middle ear effusion. The micropipets with the effusion/bacterial suspension were incubated at 37 degrees C and kept at various inclinations to the horizontal plane (15 degrees, 30 degrees and -75 degrees). All S. aureus, M. catarrhalis, alpha- and beta-haemolytic streptococci isolates examined survived in this medium for 18 h. The majority of alpha- and beta-haemolytic streptococci isolates penetrated the MEE, irrespective of the inclination of the micropipet, whereas the number of S. pneumoniae (p<0.01) and H. influenzae (p = NS) isolates penetrating the substrate increased when the micropipets were inclined at -75 degrees to the horizontal. None of the S. aureus and M. catarrhalis isolates penetrated the MEE pillar during the incubation. The present in vitro study demonstrated that MEE possesses an antibacterial property and is able to selectively hinder bacterial penetration.

Pneumococcal otitis media is frequent in young children and could lead to labyrinthitis post-implantation. To assess the risk, and methods of minimizing it by a graft to the round window around the electrode entry point, we have used a cat animal model of pneumococcal otitis media. Twenty-one kittens were used in the study. Thirty-two cochleas were implanted when the kittens were 2 months of age. Fourteen cochleas were implanted without using a graft (12 were available for study); 9 had a fascial graft, and 9 a Gelfoam graft (7 were available for study). The implanted kittens had their bullae inoculated with Streptococcus pneumoniae 2 months after implantation and were sacrificed 1 week later. There were also 9 unimplanted control ears which were inoculated when the animals were 4 months of age. Labyrinthitis occurred in 44% of unimplanted control, 50% of implanted ungrafted, and 6% of implanted grafted (fascia and Gelfoam) cochleas. There was no statistically significant difference between the unimplanted control and the implanted cochleas (p < 0.05). There was, however, a difference between the implanted-ungrafted and implanted grafted cochleas, but not between the use of fascia and Gelfoam to graft the round window entry point. As a result, the data indicates that cochlear implantation does not increase the risk of labyrinthitis following pneumococcal otitis media, but it is desirable to use fascia as a graft to the round window around the electrode entry point.

Otitis media was introduced in chinchillas by direct transbullar inoculation with either viable or formalin-inactivated Moraxella (Branhamella) catarrhalis. Both groups of animals developed middle ear fluids (MEF) and severe inflammatory changes in the tubotympanum. Pure cultures of M. catarrhalis were recovered for up to 5 days after inoculation from those animals inoculated with viable bacteria. Significantly elevated anti-M. catarrhalis antibody titers were detected in post-inoculation sera and in MEF or bullar lavages, and an increased number of IgG-bearing cells was also observed in the tubotympanum of these animals. Control chinchillas inoculated with pyrogen-free sterile saline failed to show any signs of otitis media. Our data indicate that viable M. catarrhalis induce acute otitis media in the chinchilla but that the bacteria are rapidly eliminated from the middle ear, precluding its usefulness as a model to study acute otitis media. Moreover, the same concentration of nonviable organisms also induces severe inflammatory changes in the middle ear. These data indicate that the chinchilla may be a useful model for studying the role of nonviable M. catarrhalis or its cell wall components on the induction and persistence of inflammation in the middle ear.

The local antibody response to the outer membrane protein, P6, of nontypable H. influenzae was measured in middle ear fluids of 30 children during 46 episodes of otitis media, and in nasopharyngeal secretions from 7 children evaluated on 18 occasions. Immunoglobulin G antibody to P6 was detected in 92% of middle ear fluid compared to 70% for IgM, 78% for IgA, and 45% for secretory IgA. Antibody levels ranged from a high of 249 ng/ml for IgG to a low of 11 ng/ml for IgM. Concentrations of P6 specific IgG in the middle ear fluid was directly related to the concentration in the serum, r = 0.89, p < 0.001, and inversely related to the number of bacteria present, r = -0.62, p < 0.05. In contrast, IgA and secretory IgA antibodies to P6 were common (96% and 95%, respectively) and in relatively high concentrations (33 ng/ml and 29 ng/ml, respectively) in nasopharyngeal secretions. There was no relationship between nasopharyngeal and serum levels of antibodies. These data suggest that antibody to P6 nontypable H. influenzae is common, diffuses into the middle ear spaces passively from the serum during otitis media, and is manufactured locally in the nasopharynx in response to colonization.

The proportions of secretory IgA (SIgA)-, IgG- and C3b-coated bacteria obtained from a well-defined area on the posterior wall of the nasopharynx (NPH) close to the Eustachian tube were determined. Samples taken from 25 otitis-prone (OP) and 25 non-otitis-prone (NOP) children with normal serum levels of IgA and IgG were evaluated using an immunofluorescence assay. Both groups harboured significantly more nasopharyngeal bacteria coated with IgG than with SIgA (p < 0.001). The OP children had significantly fewer SIgA-coated bacteria (p < 0.05) but more C3b-coated bacteria (p < 0.01) in the NPH than the NOP children had. No significant difference was noted between the two groups regarding IgG coating. The occurrence of Branhamella catarrhalis in the NHP was more pronounced in the OP group (p < 0.05). No significant differences in the occurrence of other middle ear pathogens (Streptococcus pneumoniae, Haemophilus influenzae, Staphylococcus aureus) or quantitative dominance of pathogens were noted between the two groups. Deficiency in SIgA coating of the nasopharyngeal bacteria may contribute to the otitis-prone condition.

Experimental otitis media induced in the chinchilla by inoculation of influenza A virus into the middle ear resulted in capillary engorgement, subepithelial hemorrhage, tissue edema and acute inflammatory cell infiltration. Quantitative morphometric measurements were made for 28 days. Ciliated cells appeared to be the primary target of this strain of influenza virus and demonstrated the greatest degree of damage. Three weeks were required to restore the ciliated epithelium in the tubotympanum to normal levels.

The quantitative bacteriology of the adenoid was studied in otitis-prone and non-otitis-prone children. alpha-hemolytic Streptococci (Viridans Streptococci) appeared to be predominant normal flora in the healthy nasopharynx. There was a decrease in alpha-hemolytic Streptococci in the otitis-prone child compared to the non-otitis-prone child. Concomitantly, there appears to be an increase in both nontypable Haemophilus influenzae (NTHI) and S. pneumoniae in the nasopharyngeal flora in the otitis-prone child. The mechanisms responsible for this alteration of the micro-ecology of bacteria of the nasopharynx may be related, in part, to factors that alter mucociliary function. These factors could be viral infection, allergy, local and systemic immunological deficiency and the indiscriminate use of antibiotics. An understanding of the relationship between the normal flora and the potential pathogens may be important in the understanding of both the pathogenesis of otitis media (OM) and possibly the treatment of this disease entity.

Samples of middle ear effusion were obtained from 16 patients with chronic suppurative otitis media (COM) (20 ears, age range from 1 1/12 to 69 years) and 13 patients with secretory otitis media (SOM) (15 years, age range from 8 months to 13 8/12 years). Qualitative and quantitative bacteriological analyses of the effusions were performed and the intensity of immunoglobulin G (IgG) and complement component C3b adhering to the bacteria was estimated using immunofluorescence technique. In COM effusions, S. aureus in particular was intensely opsonized, whereas Ps. aeruginosa showed minimal, if any, coating with IgG and C3b. SOM effusions exhibited extremely sparse IgG- and C3b-coated bacteria. The difference in IgG and C3b coated bacteria between COM and SOM effusions was significant (p less than 0.01). Specific (IgG) as well as non-specific (C3b) coating of the bacteria that have gained access to the middle ear cavity is of importance for the host defence.

Aerobic and anaerobic semiquantitative bacteriological cultures were taken from 110 mucoid middle ear effusions and the respective ear canals of 74 patients with secretory otitis media (SOM). Additionally, mucosal pieces from 20 non-inflamed middle ears and swabs from the ear canals were cultured similarly. Bacteria were found in 35 effusions and 65 ear canals with SOM; in both sites the most frequent species were S. epidermidis and S. aureus, and the species distributions were not significantly different in the sites. Ten effusions grew bacteria not culturable in the respective ear canal samples. Anaerobes were found in one effusion only. Nine non-inflamed middle ears revealed bacteria; the species distribution was no different from SOM, and four of the bacteria were not found in the ear canal of the same ear. In conclusion, there may be bacteria in the middle ear in the absence of inflammation and in SOM, but the role of viable bacteria seems to be nil in an established secretory otitis media.

Any functional disturbance in the auditory tube may be documented morphologically. We demonstrated in case of a block changes within the tubal mucosa and in the adjacent salivary glands. Complete obliteration of the lumen is a very rare instance caused only by severe trauma or as a possible result of heavy inflammatory damage to the mucosa. A lack of ventilation produces in the tympanic cleft a vacuum, followed by a typical effusion out of the altered mucosa. Anaerobic conditions favour hyper and metaplastic transformation of the epithelium. The clinical picture resembles the non-purulent, closed form of otitis, serous otitis media. The missing clearance makes the discharge within the tympanic cleft a great challenge to the mucosa. Granulation tissue proliferates, an enzyme production is initiated and phagocytes help to eliminate or to organize the middle ear content. The clinical picture corresponds to otitis media adhaesiva. If the auditory tube is blocked long enough, the healing result leads to the atelectatic tympanon caused by scare tissue, dystrophic calcification, fatty degeneration of granulation tissue, fibrocystic transformation of the mucosa. The ossicular chain, if not destroyed or interrupted, is fixed. A very dangerous condition is caused by retractionpockets within the ear drum membrane. They give rise to secondary acquired cholesteatoma. In the beginning of the whole process we see the nonfunctioning auditory tube, provoked by an infection. The development of the tubal tonsil and the perivascular aggregations of immunocompetent cells lead to the opinion, that the tube is an immunological not only a mechanical barrier against ascending infections. Favoured by antibiotic treatment the inflammation is localized by the body's own defence within the tympanic tube and causes the blockage, the loss of function, which influences heavily the middle ear and its lining.

Specimens of middle ear effusion and adenoid tissue were studied for bacteria and pneumococcal capsular antigen in 107 patients with secretory otitis media. 120 of 163 middle ear effusion samples (73.6%) were negative on bacterial culture. Hemophilus influenzae was present in 9.2% and Streptococcus pneumoniae in 1.8%. Hemophilus influenzae was cultured from 44.8% and Streptococcus pneumoniae from 35.5% of 107 adenoid tissue specimens. Free pneumococcal capsular antigen was demonstrated in 10.4% of the middle ear fluids and this figure rose to 23% when antigen was liberated from the immune complexes by heating. The corresponding figures for adenoid tissue suspension were 27.1% and 39%. The adenoid tissue or the lymphoid tissue of the entire oropharynx could act as the source of antigen which could maintain immune complex disease in some patients suffering from secretory otitis media.

A total of 5217 middle ear fluid (MEF) samples obtained from 1203 children with otitis media, aged 3 months to 6 years, were studied for the presence of Branhamella catarrhalis (Br) between Oct. 1977 and Sept. 1981. Br grew in 10.2% of 3497 MEFs of acute otitis media (AOM), with almost the same frequency in the very first and subsequent attacks. During the first 4 years of life the percentage did not vary much; among older children it seemed to decrease. The overall prevalence of Br in AOM did not change during the study period. Br alone grew in 72.4% of acute MEFs with Br; with other bacteria the respective figure was 82.9% (p less than 0.001). Acute attacks with bilateral Br were found in 22.8% of attacks with Br. In 1720 non-acute MEFs obtained at postacute control visits, Br was isolated in only 7.0%. The proportion of beta-lactamase-producing strains among the 2419 otitis-Br strains tested in two laboratories of the two study regions showed an increase from 27.1% and 21.1% in 1980 to 57.6% and 38.6% in 1983, respectively (p less than 0.001).