Sequential measurement of Trypanosoma cruzi parasitic load in endomyocardial biopsies for early detection and follow‐up of Chagas disease reactivation after heart transplantation

Abstract

Background Reactivation of Chagas disease after heart transplantation is characterized by proliferation and dissemination of Trypanosoma cruzi parasites to several organs. Reactivation affecting the allograft can simulate acute cellular rejection, from which it should be distinguished through the analysis of endomyocardial biopsies (EMB). Methods We evaluated retrospectively 100 EMB collected in the first year of follow‐up from 13 heart‐transplanted, chagasic patients who presented reactivation and were successfully treated. Additionally, 37 EMB from 8 patients who did not present reactivation constituted the control group. We reviewed histopathology and performed a real‐time PCR‐based assay in order to evaluate the T cruzi parasitic load of each EMB. Results The parasitic load of the EMB at the time of reactivation ranged from 22.80 to 190 000/106 cells (median: 1555). In 6 patients, none of the EMB obtained prior to reactivation amplified T cruzi DNA. On the other hand, 10 EMB from 7 patients, obtained 9‐105 days before reactivation (median: 26 days), showed parasitic load ranging from 8.25 to 625/106 cells (median: 167.55). In all patients, the parasitic load increased at the time of reactivation, usually sharply. After initiation of treatment, all patients showed negative PCR or a dramatic reduction of the parasitic load in the following EMB. None of the EMB from the control group amplified T cruzi DNA. Conclusions Sequential measurement of T cruzi parasitic load in EMB is useful for monitoring Chagas disease reactivation after heart transplantation. Its increase suggests imminent reactivation and its decrease after treatment indicates favorable evolution for cure of the episode of reactivation.

Myocarditis, histological detection and parasitic load of Trypanosoma cruzi in endomyocardial biopsies presenting with reactivation of Chagas disease after heart transplantation

“…1 In two previous reports, we evaluated the parasitic load of 16 endomyocardial biopsies presenting with reactivation of Chagas disease, using quantitative polymerase chain reaction (PCR). 2,3 We re-examined those biopsies in order to evaluate the presence and intensity of myocarditis and T. cruzi parasites.…”

Transplantation for chagas’ disease: closing the knowledge gap

“…Several cohort studies demonstrate that PCR positivity precedes the clinical manifestations of CDR [49,[65][66][67][68][69]. In the USA, serial monitoring with white blood cell buffy coat microscopy and PCR is recommended weekly for the first two months posttransplant, every two weeks in the third month, and then monthly for at least six months.…”

Molecular and Clinical Aspects of Chronic Manifestations in Chagas Disease: A State-of-the-Art Review

“…On the other hand, heart transplantation remains another option for the treatment of advanced Ch-CMP [177][178][179]. Nevertheless, the risk of infection reactivation in the context of immunosuppression lingers and evidence regarding its prevention, diagnosis, and treatment is scarce [180][181][182][183].…”