title: Angioedema in a child with a liver transplant, intussusception, and normal c4 levels.
abstract: Swelling is a common chief complaint among patients. Swelling and hives are not typical of hereditary angioedema. Organ transplantation drugs are associated with angiodema and may complicate diagnosis. Our objective was to manage a complex case of angioedema in a setting of rashes and liver transplantation. We present an illustrative case of angioedema, rashes, and intussusception in a setting of a liver transplant and tacrolimus use with a family history of autoimmune disease. Treatment with the kallikrein inhibitor, kalbitor, eliminated angioedema and intussusception, though not permanently. Serial C1 esterase [corrected] inhibitor levels were only suppressed during severe attacks of angioedema. C1q autoantibody was elevated. Although 95% of cases of hereditary angioedema (HAE) have low [corrected] C4 levels, those with C1q immune complexes have autoantibodies leading to low-grade inflammation and eventual consumption of C1 esterase inhibitor levels with C4 unaffected. Rashes associated with angioedema are not urticarial. Physicians should learn to recognize the signs of attacks of HAE.
authors.affiliation: Allergy Diagnostic Unit, Stony Brook University Medical Center, East Setauket, New York, USA. anthony.szema@stonybrook.edu
authors.forename: Anthony M
authors.initials: AM
authors.lastname: Szema
mesh_terms: D015746:Abdominal Pain; D000293:Adolescent; D000799:Angioedema; D001323:Autoantibodies / Q000276:immunology / Q000378:metabolism; D015922:Complement C1q / Q000276:immunology; D003181:Complement C4 / Q000378:metabolism; D003937:Diagnosis, Differential; D006633:Histamine Antagonists / Q000627:therapeutic use; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000175:diagnosis* / Q000188:drug therapy / Q000276:immunology / Q000503:physiopathology; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D007443:Intussusception; D007610:Kallikreins / Q000037:antagonists & inhibitors; D016031:Liver Transplantation; D008297:Male; D010455:Peptides / Q000008:administration & dosage*; D012882:Skin Tests; D016559:Tacrolimus / Q000627:therapeutic use
chemical_list: D001323:Autoantibodies; D003181:Complement C4; D006633:Histamine Antagonists; D007166:Immunosuppressive Agents; D010455:Peptides; C511194:ecallantide; D015922:Complement C1q; D007610:Kallikreins; D016559:Tacrolimus