ASSOCIATION BETWEEN BLOOD EOSINOPHIL COUNTS AND ACUTE CARDIAC AND PULMONARY ALLOGRAFT-REJECTION

Background: Peripheral blood eosinophilia is a particularly early and specific marker of both renal and hepatic allograft rejection. Therefo re we evaluated the relationship between blood eosinophil counts and c ardiac and pulmonary allograft rejection. Methods: Differential blood counts were available within 3 days before 383 endomyocardial biopsy s pecimens in 56 heart transplant recipients. Blood counts were also ava ilable before 84 treated rejection episodes and 28 transbronchial biop sy specimens showing no rejection in 58 lung transplant recipients. Re sults: Cardiac allograft rejection: There was a significant associatio n between the mean maximum blood eosinophil count and treated acute re jection (p < 0.01) and a linear relationship between this eosinophil c ount and the histologic grade of rejection (p < 0.01). The first incre ase in eosinophils occurred at a median of 4 days before treated rejec tion. Pulmonary allograft rejection: The mean maximum blood eosinophil count was 0.14 x 10(9)/L (95% confidence interval = 0.10, 0.18) prece ding treated rejection, and this was significantly greater than the me an maximum blood eosinophil count of 0.07 x 10(9)/L (confidence interv al = 0.05, 0.09) measured when there was no rejection or during infect ion (p = 0.01). The first increase in eosinophil occurred at a median of 5 days before treated rejection. There was no relationship between blood neutrophil counts and either cardiac or pulmonary allograft reje ction. Conclusions: An increase in peripheral blood eosinophils but no t neutrophils is a specific and early marker of clinically significant rejection of both cardiac and pulmonary allografts. Furthermore, the maximum blood eosinophil count measured in the 3 days before rejection is linearly related to the severity of cardiac allograft rejection.