Angiotensin converting enzyme inhibitor-induced angioedema more prevalent in transplant patients

Background: Angioedema in association with angiotensin converting enzyme inhibitor (ACEI) use is rare, but serious. Which patients are predisposed to the reaction and whether it involves an immune mechanism remain unclear. Objectives: To determine the frequency of ACEI angioedema in immunosuppressed cardiac and renal transplant patients. Methods: This was a retrospective chart review of all adult cardiac (n = 156) and renal (n = 341) transplant patients followed at our hospital (years 1985 to 1995). Results: Of 105 cardiac and 91 renal transplant patients on a combination of immunosuppressive and ACEI therapy, 5 (4.8%) cardiac and 1 (1%) renal patients developed angioedema. This prevalence of ACEI angioedema among cardiac and renal transplant patients is 24 times and 5 times higher, respectively, than that observed in the general population (0.1% to 0.2%). Reactions often appeared after prolonged ACEI use (average 19 months; range 3 days to 6.3 years). African-Americans were significantly more likely to experience ACEI-associated angioedema (P =.034), especially among the cardiac patients where 4 of 5 reactors were African-American, Conclusions: For unclear reasons, ACEI-induced angioedema (often late-onset) is more prevalent among immunosuppressed cardiac and renal transplant patients. Additionally, African-Americans are over-represented among those developing the reaction.