title: [Acquired C1 esterase inhibitor deficiency and lymphoproliferative syndromes].
abstract: About 20 cases of acquired C1 esterase inhibitor deficiency have been reported in association with malignant lymphomas. We describe 3 such patients. The 3 patients studied were asymptomatic and had low C1q level. Danazol administration resulted in an increase of C1 esterase inhibitor in 2 patients. The complement activation in acquired C1 esterase inhibitor deficiency could be explained by interaction with pathological cells of the spleen, the blood or the bone-marrow. The mechanism of decrease of C1 INH is discussed.
mesh_terms: D000368:Aged; D003174:Complement C1 Inactivator Proteins / Q000172:deficiency*; D003165:Complement System Proteins / Q000032:analysis; D003613:Danazol / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008232:Lymphoproliferative Disorders / Q000201:enzymology / Q000276:immunology* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D010956:Plasmapheresis; D013997:Time Factors
chemical_list: D003174:Complement C1 Inactivator Proteins; D003165:Complement System Proteins; D003613:Danazol
vernacular_title: Déficit acquis en inhibiteur de la C1 estérase et syndrome lymphoprolifératif.