"Quilty effect" in heart transplantation: is it related to acute rejection?

"Quilty effect" is a lymphocytic infiltrate bulging in the endocardium of cardiac allografts with or without affectation of myocardium. It has been related with cyclosporine treatment. We have reviewed the morphology of 527 endomyocardial biopsy specimens from 46 transplant patients to study the significance and relation of Quilty effect with acute rejection. Paraffin immunoperoxidase studies were performed in 56 cases with Quilty effect or acute rejection. We graded acute myocardial rejection into four degrees according to the Hannover classification. A total of 126 biopsy specimens (24%) showed Quilty effect. Fifty-nine specimens (46.8%) showed different degrees of acute rejection in addition to Quilty effect. If we consider specimens with acute rejection grade greater than or equal to II, which require treatment, the frequency of the association of Quilty effect and acute rejection is statistically significant (p less than 0.01). In cases of acute rejection, the percentage of cases with Quilty effect was higher in cases with the highest degrees of acute rejection. The response of acute rejection to antirejection treatment was similar in all cases with or without Quilty effect. Immunohistochemical study showed a predominance of T lymphocytes in both Quilty effect and in the myocardium of acute rejection. We conclude that Quilty effect is a manifestation of acute rejection, modified by many factors, such as cyclosporine treatment. The finding of isolated Quilty effect may signal the prompt development of an acute rejection episode.