title: Acquired C1 esterase-inhibitor deficiency: case report with emphasis on complement and kallikrein activation during two patterns of clinical manifestations.
abstract: A case of severe angioedema with several episodes of life-threatening attacks during a follow-up of 7 years is presented. Although the biologic profile is that of an acquired C1 INH deficiency, no lymphoproliferative malignancy or immune-complex disease could be proven until now. However, the patient has had a small monoclonal IgG lambda-gammopathy for 4 years. During the last 4 years, edematous manifestations have stopped. The patient now suffers at regular intervals of about a week from short-lasting attacks with digestive and vasomotor symptoms. This clinical evolution is accompanied by a worsening in the complement abnormalities. The digestive and vasomotor attacks were found to be correlated with sudden prekallikrein and high-molecular-weight kininogen consumption. These findings demonstrate that prekallikrein is activated during acquired C1 INH deficiency and that the products of this pathway such as bradykinin are probably responsible for a part of the clinical manifestations associated with this disorder.
mesh_terms: D000368:Aged; D000799:Angioedema / Q000503:physiopathology*; D001798:Blood Proteins / Q000378:metabolism; D003167:Complement Activation; D003174:Complement C1 Inactivator Proteins / Q000172:deficiency*; D004890:Erythema / Q000503:physiopathology; D005767:Gastrointestinal Diseases / Q000503:physiopathology; D006801:Humans; D007610:Kallikreins / Q000502:physiology; D008297:Male; D010507:Periodicity
chemical_list: D001798:Blood Proteins; D003174:Complement C1 Inactivator Proteins; D007610:Kallikreins