TY - JOUR
T1 - Unmasking of acquired autoimmune C1-inhibitor deficiency by an angiotensin-converting enzyme inhibitor
AU - Kleiner, Gary I.
AU - Giclas, Patricia
AU - Stadtmauer, Gary
AU - Cunningham-Rundles, Charlotte
N1 - Funding Information:
* Division of Clinical Immunology, Mount Sinai-New York University Medical Center, New York, New York. † Diagnostic Complement Laboratory, National Jewish Medical Center, Denver, Colorado. This study was supported by Grants FDA-001679, AI-46732, and the Jeffrey Modell Foundation. Received for publication May 1, 2000. Accepted for publication in revised form October 4, 2000.
PY - 2001
Y1 - 2001
N2 - Background: A majority of angioedema arise from unknown etiologies. Angioedema may also arise from medications or deficiency of C1-esterase inhibitor (C1-INH); either of these may lead to recurrent, sometimes life-threatening attacks of subcutaneous or submucosal edema if the angioedema involves the tongue, throat, or larynx. We describe a patient with unknown acquired C1-INH deficiency, who experienced only mild attacks of angioedema before treatment with an angiotensin-converting enzyme (ACE) inhibitor. This therapy led to life-threatening respiratory distress. Objective: To investigate this patient's life-threatening angioedema. Methods: Serum protein electrophoresis and immunofixation were performed. The titer of anti-C1-inhibitor autoantibody was determined by ELISA, and the specificity of the autoantibody demonstrated by using purified C1-INH to block binding in the ELISA. Finally, fractions from the immunoelectrophoresis gel were tested for C1-INH autoantibody by ELISA. Results: Complement activation was documented by reduced C1-INH, C1q, and C4, and the patient was found to have an autoantibody of IgG2 isotype specific for C1-INH. After discontinuation of the ACE inhibitor, he continued to have decreased C1-INH and positive C1-INH autoantibodies. Conclusions: This case describes a patient who had a history of mild facial and extremity swelling with abdominal symptoms before ACE inhibitor treatment; this medication resulted in life-threatening respiratory distress. The use of the ACE inhibitor may have unmasked this patient's acquired autoimmune C1-INH deficiency.
AB - Background: A majority of angioedema arise from unknown etiologies. Angioedema may also arise from medications or deficiency of C1-esterase inhibitor (C1-INH); either of these may lead to recurrent, sometimes life-threatening attacks of subcutaneous or submucosal edema if the angioedema involves the tongue, throat, or larynx. We describe a patient with unknown acquired C1-INH deficiency, who experienced only mild attacks of angioedema before treatment with an angiotensin-converting enzyme (ACE) inhibitor. This therapy led to life-threatening respiratory distress. Objective: To investigate this patient's life-threatening angioedema. Methods: Serum protein electrophoresis and immunofixation were performed. The titer of anti-C1-inhibitor autoantibody was determined by ELISA, and the specificity of the autoantibody demonstrated by using purified C1-INH to block binding in the ELISA. Finally, fractions from the immunoelectrophoresis gel were tested for C1-INH autoantibody by ELISA. Results: Complement activation was documented by reduced C1-INH, C1q, and C4, and the patient was found to have an autoantibody of IgG2 isotype specific for C1-INH. After discontinuation of the ACE inhibitor, he continued to have decreased C1-INH and positive C1-INH autoantibodies. Conclusions: This case describes a patient who had a history of mild facial and extremity swelling with abdominal symptoms before ACE inhibitor treatment; this medication resulted in life-threatening respiratory distress. The use of the ACE inhibitor may have unmasked this patient's acquired autoimmune C1-INH deficiency.
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U2 - 10.1016/S1081-1206(10)62496-9
DO - 10.1016/S1081-1206(10)62496-9
M3 - Article
C2 - 11345293
AN - SCOPUS:0035063589
SN - 1081-1206
VL - 86
SP - 461
EP - 464
JO - Annals of Allergy, Asthma and Immunology
JF - Annals of Allergy, Asthma and Immunology
IS - 4
ER -