[Experimental studies on the question of the enzymatic destruction of the ossicular bones during middle ear inflammations (author's transl)]. / Experimentelle Untersuchungen zur Frage der enzymbedingten Gehörknöchelchendestruktion im Verlauf einer chronischen Mittelohrentzündung

The proteolytic activity of purulent middle ear secretions from patients with cholesteatoma, chronic otitis media, acute otitis media and radical mastoid cavities were investigated. The proteolytic activity in the secretions from cases with cholesteatoma is higher than from patients with other chronic otitis media. The collagenolytic effect of the matrix of cholesteatoma combined with the high level of the bacterial and leukocytic proteinases in the middle ear secretions is undoubtedly one of the main factors in the destruction of the ossicular bones.

[Detection of split products of the immunoglobulins IgG, IgA and IgM during chronic otitis media (author's transl)]. / Der Nachweis von Spaltprodukten der Immunglobuline IgG, IgA, IgM bei chronischen Mittelohreiterungen

Proteolytic enzymes such as pepsine or papaine are able to split IgG antibodies into large fragments in vitro. These immunoglobulin fragments (IgG, IgA, IgM) were now detected in vivo from the purulent secretions of cholesteatoma, chronic otitis media and radical mastoid cavities. During chronic otitis media the intact immunoglobulins are split due to the proteolytic activity of neutral proteinases. These fragments were qualitatively and quantitatively investigated by means of various immunological procedures. After the immunoelectrophoretic separation of the purulent middle-ear-secretions and after diffusion against anti-IgG-, anti-IgA- and anti-IgM- serum double precipitate lines could be observed especially in middle-ear-secretion with a bacterial flora of pseudomonas aeruginosa (pyocyanea) and of the proteus-providencia-group. This was the first proof of the presence of split products of the immunoglobulins. The exact demonstration of these split products could be carried out by gel-filtration and fractionation of the intact and split immunoglobulins. During chronic otitis media intact immunoglobulins are split by leucocytic and extracellular bacterial proteinases into fragments of different molecular weight. The most malignant extracellular proteinases with the greatest proteolytic activity against intact immunoglobulins are the bacterial proteinases of pseudomonas aeruginosa. These proteinases can not be inhibited by the other serum proteinaseinhibitors except for alpha-2-macroglobulin of the human blood serum. This inhibitor has a very high molecular weight so that we can not find it in a higher concentration in the middle-ear-secretion. We can liberate this inhibitor by injuring the blood vessels during a tympanoplasty. In this way we get an inhibitory effect against these proteinases and combined with an appropriate antibiotic therapy we can cure a chronic otitis media.