Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024141 (systemic lupus erythematosus)
 44,322 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Deficiencies of individual complement proteins may be accompanied by SLE or related syndromes. Deficiencies of the classic activation pathway are often involved. In cases of C4 and C2 deficiency, there is evidence that this association occurs more frequently than would be expected by chance. The clinical picture differs from classic SLE. There is an increased frequency of skin involvement, a decreased frequency of renal disease, low or absent levels of antibody to native DNA, and increased levels of anti-Ro (SS-A). The mechanism for the association probably involves the effects of C3 and C4 on the precipitation of immune complex solubility, or on their processing through cell surface c4b/c3b receptors on phagocytes. Disseminated or recurrent Neisseria infections are common in patients lacking the constituents of the terminal MAC that are important in killing these organisms.
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PMID:Rheumatic diseases and inherited complement deficiencies. 868 May 30

The complement system is composed of more than 30 serum and membrane-bound proteins, all of which are needed for normal function of complement in innate and adaptive immunity. Historically, deficiencies within the complement system have been suspected when young children have had recurrent and difficult-to-control infections. As our understanding of the complement system has increased, many other diseases have been attributed to deficiencies within the complement system. Generally, complement deficiencies within the classical pathway lead to increased susceptibility to encapsulated bacterial infections as well as a syndrome resembling systemic lupus erythematosus. Complement deficiencies within the mannose-binding lectin pathway generally lead to increased bacterial infections, and deficiencies within the alternative pathway usually lead to an increased frequency of Neisseria infections. However, factor H deficiency can lead to membranoproliferative glomerulonephritis and hemolytic uremic syndrome. Finally, deficiencies within the terminal complement pathway lead to an increased incidence of Neisseria infections. Two other notable complement-associated deficiencies are complement receptor 3 and 4 deficiency, which result from a deficiency of CD18, a disease known as leukocyte adhesion deficiency type 1, and CD59 deficiency, which causes paroxysmal nocturnal hemoglobinuria. Most inherited deficiencies of the complement system are autosomal recessive, but properidin deficiency is X-linked recessive, deficiency of C1 inhibitor is autosomal dominant, and mannose-binding lectin and factor I deficiencies are autosomal co-dominant. The diversity of clinical manifestations of complement deficiencies reflects the complexity of the complement system.
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PMID:Clinical significance of complement deficiencies. 1975 39