muramidase and Otitis-Media-with-Effusion

Serous otitis media is usually responsive to medical treatment, whereas mucoid otitis media is not. The present study was undertaken to elucidate the compositional difference between serous and mucoid effusion and to investigate whether MUC5AC acts as a major mucin in the middle ear mucosa with mucoid otitis media.. This study involved a chemical analysis of middle ear effusion and immunostaining of the middle ear mucosa.. Middle ear effusion samples were collected from 27 patients with mucoid otitis media and 18 patients with serous otitis media. The levels of mucin, lysozyme, secretory immunoglobulin A, and interleukin-8 were measured by dot blotting or enzyme-linked immunosorbent assay. Periodic acid-Schiff and immunohistochemical staining with monoclonal anti-MUC5AC antibody were performed on the serial sections of middle ear mucosa with mucoid otitis media.. Mucoid effusions contained higher levels of mucin, lysozyme, secretory immunoglobulin A, and interleukin-8 than did serous effusions. Immunohistological study revealed that MUC5AC mucin was expressed in only a small portion of the goblet cells of middle ear mucosa with mucoid otitis media.. The study suggests that both serous secretions and mucin might make the middle ear effusion more viscous and that mucins other than MUC5AC might have a major role in the viscosity of middle ear effusion. Further study is necessary to identify the major mucins in the middle ear effusion of otitis media with effusion.

Topics: Child; Child, Preschool; Ear, Middle; Female; Humans; Immunoglobulin A, Secretory; Interleukin-8; Male; Mucin 5AC; Mucins; Mucous Membrane; Mucus; Muramidase; Otitis Media with Effusion; Viscosity

Middle ear infection with Streptococcus pneumoniae is important in the pathogenesis of acute and chronic otitis media, and lysozyme in middle ear fluid (MEF) is an important inflammatory mediator in this disease. To determine the source of lysozyme during the early period of acute pneumococcal otitis media, chinchillas were irradiated to induce neutropenia, and their middle ears were inoculated with heat-killed, encapsulated pneumococci. The number of inflammatory cells and concentration of lysozyme were measured in MEF between 6 and 72 hours after inoculation. In pneumococcus-inoculated ears, the mean number of inflammatory cells but not lysozyme was significantly lower in MEF from irradiated animals than that from nonirradiated animals at 6 hours. Since lysozyme accumulated in MEF before the influx of inflammatory cells in irradiated animals, the initial release of this inflammatory mediator is most likely not from inflammatory cells; and mucosal epithelial cells, the only other known source of lysozyme in the middle ear environment, were the probable source induced by the direct stimulation of pneumococci. Inflammatory cells may contribute lysozyme later in the inflammatory response, since cellular and lysozyme concentrations in irradiated and nonirradiated animals were similar between 24 and 72 hours. These results suggest that future therapeutic interventions to limit middle ear inflammation in acute otitis media may need to recognize the direct action of pneumococcal cells or their envelope components on middle ear epithelium.

Topics: Acute Disease; Animals; Chinchilla; Leukocyte Count; Muramidase; Otitis Media with Effusion; Pneumococcal Infections

Endotoxin levels and lysosomal protease (collagenase, cathepsin B, and lysozyme) activity were measured in 104 middle ear effusions (MEEs) from patients with otitis media with effusion (OME). The MEE samples were classified into four groups: pediatric serous, mucoid, and acute, and adult serous. Endotoxin levels and lysosomal protease activity in MEEs were significantly different in the following order: adult less than serous less than mucoid less than acute groups, indicating that both endotoxin and lysosomal proteases are more closely related to the pathogenesis of pediatric chronic OME than to adult OME. In pediatric serous and mucoid effusions, endotoxin level had a significant correlation with activity of the lysosomal proteases. In conclusion, endotoxin enhances leukocyte infiltration into the middle ear, and lysosomal proteases released from leukocytes damage the middle ear mucosa and thereby prolong mucosal inflammation, which may be responsible for delayed recovery from acute OME.

Topics: Acute Disease; Adolescent; Adult; Aged; Aged, 80 and over; Cathepsin B; Child; Child, Preschool; Chronic Disease; Endotoxins; Humans; L-Lactate Dehydrogenase; Microbial Collagenase; Middle Aged; Muramidase; Otitis Media with Effusion; Proteins

Although previous studies have shown that prostaglandins (PGs), leukotrienes (LTs), and other arachidonic acid (AA) metabolites play an important role in the pathogenesis of otitis media with effusion (OME), the exact role of each AA metabolite in OME is still unknown. The purpose of this study was to examine the effect of several individual AA metabolites alone or in combination and AA itself on experimental otitis media in chinchillas. Normal chinchillas were inoculated daily with normal saline, PGE2, LTC4, LTC4 + PGE2, and AA through the superior bullae over 7 days. Animals were followed by otoscopy and tympanometry, samples of middle ear effusion were collected for biochemical assay, and temporal bones were processed for histopathology. The highest number of ears that developed OME was in the group inoculated with PGE2 + LTC4. The degree of inflammatory change was more pronounced in groups injected with LTC4 than any other group. The findings of this study suggest that eicosanoids PGE2, LTC4, and AA alone or in combination inoculated into the middle ear can induce OME.

Topics: 6-Ketoprostaglandin F1 alpha; Animals; Arachidonic Acid; Arachidonic Acids; Chinchilla; Dinoprost; Dinoprostone; Hydroxyeicosatetraenoic Acids; Leukocytes; Leukotriene B4; Mucous Membrane; Muramidase; Otitis Media with Effusion; Prostaglandin D2; SRS-A

Lysozyme concentrations in middle ear effusion and serum were determined in patients with otitis media with effusion. Lysozyme concentrations in middle ear effusion were significantly higher than in serum. Children with mucoid otitis media showed significantly higher levels of lysozyme in middle ear effusion than children with serous otitis media and adults with otitis media with effusion. Higher levels of lysozyme were observed in the group of children younger than 5 years old compared with the age group of 6- to 10-year-olds. Lysozyme concentrations of middle ear effusion in adults were significantly lower than those of mucoid otitis media in children. These results indicate that lysozyme plays an important role in the disease process of otitis media.

Topics: Adult; Age Factors; Child; Child, Preschool; Humans; Muramidase; Otitis Media with Effusion

We studied the contribution of pneumococcal cell wall to the pathogenesis of otitis media in chinchillas after middle ear inoculation of killed, encapsulated type 7F Streptococcus pneumoniae; killed, unencapsulated R6 S. pneumoniae; and isolated R6 pneumococcal cell wall. Ears inoculated with encapsulated and unencapsulated pneumococci had significantly higher concentrations of polymorphonuclear and mononuclear leukocytes and lysozyme in middle ear fluid and developed more epithelial metaplasia and granulation tissue than did saline-inoculated ears. The mean concentration of lysozyme in middle ear fluid was higher in ears inoculated with killed, unencapsulated than encapsulated pneumococci. The middle ear mucoperiosteum of ears inoculated with pneumococcal cell wall showed significantly more polymorphonuclear leukocytes, epithelial metaplasia, subepithelial congestion, and granulation tissue than did control ears. Because nonviable, unencapsulated pneumococci and pneumococcal cell wall caused middle ear inflammation in the chinchilla model of otitis media, it is possible that cell envelope and cell wall components released during bacterial lysis may contribute to chronic otitis media with effusion in humans.

Topics: Acute Disease; Animals; Cell Wall; Chinchilla; Chronic Disease; Ear, Middle; Leukocyte Count; Leukocytes, Mononuclear; Muramidase; Neutrophils; Otitis Media with Effusion; Periosteum; Streptococcus pneumoniae; Temporal Bone

Two Chinese patients with sinus histiocytosis and massive lymphadenopathy are reported. The results of enzyme and immunohistochemical studies are presented.

Topics: Acid Phosphatase; Adult; alpha 1-Antitrypsin; Asian People; Biopsy; Child; China; Esterases; Female; Histiocytes; Humans; Immunoenzyme Techniques; Immunoglobulins; Lymph Nodes; Lymphatic Diseases; Male; Muramidase; Otitis Media with Effusion; S100 Proteins

The sequential cytologic and biochemical events of middle ear effusion (MEE) were studied in experimental models of serous otitis media (SOM) and purulent otitis media (POM) in chinchilla. In the SOM model, the initial appearance of neutrophils was followed by macrophages. In the POM model, neutrophils were the predominant cells in MEE and the number of neutrophils was about 100-fold higher than in the SOM model. The activity of lysozyme in MEE was higher in POM than in SOM and correlated with the number of neutrophils and mononuclear phagocytes. The results of the present study suggest that neutrophils and mononuclear phagocytes are one of the main sources for lysozyme levels in MEE during otitis media.

Topics: Animals; Chinchilla; Muramidase; Otitis Media; Otitis Media with Effusion; Otitis Media, Suppurative; Pneumococcal Infections; Time Factors

Topics: Adolescent; Adult; Aged; Animals; Bacterial Infections; Child; Child, Preschool; Dogs; Ear, Middle; Eustachian Tube; Food Hypersensitivity; Gases; Humans; Hypersensitivity; Immunoglobulin E; Infant; Lymph; Middle Aged; Mucus; Muramidase; Otitis Media; Otitis Media with Effusion; Perilymph

Topics: Animals; Child; Child, Preschool; Chinchilla; Exudates and Transudates; Female; Humans; Infant; L-Lactate Dehydrogenase; Male; Muramidase; Otitis Media; Otitis Media with Effusion; Otitis Media, Suppurative; Penicillins