Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0085437 (bacterial meningitis)
 4,038 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Of 44 children who recovered from an attack of bacterial meningitis, 3 (7%) were found to have IgG subclass deficiency, 5 (11%) had IgA deficiency and 22 (50%) had raised IgE levels. These results suggest that immunoglobulin abnormalities may be an important predisposing factor in some cases of bacterial meningitis.
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PMID:Deficiency of IgG subclasses and IgA, and elevation of IgE in children with a past history of bacterial meningitis. 186 83

A patient with recurrent bacterial meningitis who lacked circulating C8, serum IgA, and secretory IgA is reported. The combined absence of C8 and IgA deficiency has not been previously noted. Although the association of disseminated neisserial infection and absence of the terminal complement components is now well established, the deficiency of bactericidal capability as well as mucosal humoral defense may have been additive in predisposing the patient to recurrent meningitis. The pedigree was uninformative regarding possible linkage of these two uncommon genetic errors.
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PMID:Recurrent bacterial meningitis associated with C8 and IgA deficiency. 731 Jan 73

IgA1 protease activity, which allows bacteria to cleave human IgA1 in the hinge region, represents a striking example of convergent evolution of a specific property in bacteria. Although it has been known since 1979 that IgA1 protease is produced by the three leading causes of bacterial meningitis in addition to important urogenital pathogens and some members of the oropharyngeal flora, the exact role of this enzyme in bacterial pathogenesis is still incompletely understood owing to lack of a satisfactory animal model. Cleavage of IgA1 by these post-proline endopeptidases efficiently separates the monomeric antigen-binding fragments from the secondary effector functions of the IgA1 antibody molecule. Several in vivo and in vitro observations indicate that the enzymes are important for the ability of bacteria to colonize mucosal membranes in the presence of S-IgA antibodies. Furthermore, the extensive cleavage of IgA sometimes observed in vivo, suggests that IgA1 protease activity results in a local functional IgA deficiency that may facilitate colonization of other microorganisms and the penetration of potential allergens. It has been hypothesized that IgA1 protease activity of Haemophilus influenzae, Neisseria meningitidis, and Streptococcus pneumoniae, under special immunological circumstances, allows these bacteria to take advantage of specific IgA1 antibodies in a strategy to evade other immune factors of the human body. The decisive factor is the balance between IgA antibodies against surface antigens of the respective bacteria and their IgA1 protease. Recent studies have shown that serine-type IgA1 proteases of H. influenzae, meningococci, and gonococci belong to a family of proteins used by a diverse group of Gram-negative bacteria for colonization and invasion.
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PMID:Biological significance of IgA1 proteases in bacterial colonization and pathogenesis: critical evaluation of experimental evidence. 870 38