Aplastic Anemia and Chagas Disease: T. cruzi Parasitemia Monitoring by Quantitative PCR and Preemptive Antiparasitic Therapy

Abstract

Background: Aplastic anemia is a rare and life-threatening condition, seldomly witnessed concomitantly with Chagas disease. We aim to discuss the management of these patients under risk of chronic Chagas disease reactivation (CDR), a severe condition with a high morbimortality that occurs in chronic Chagas disease patients under immunosuppression. Case reports: Trypanosoma cruzi (T. cruzi) parasitemia was monitored in three patients for 4–58 months by conventional PCR (cPCR), quantitative PCR (qPCR), microhematocrit/buffy coat, blood culture, and/or xenodiagnosis. One patient received antiparasitic treatment (benznidazole) and the other received allopurinol. Although parasitemia was controlled during and after benznidazole treatment at 300 mg/d for 51 days, in one patient, hematologic parameters worsened continuously before, during, and after treatment. Allopurinol led only to the temporary suppression of T. cruzi parasitemia in the second patient, but after danazol and hematological improvement, parasitemia became undetectable until the end of monitoring. Discussion and Conclusion: Unexpected undetectable or low parasitemia by cPCR/qPCR was reported. We show that the monitoring of parasitemia by qPCR and the use of preemptive therapy when the parasitemia was positive proved to be beneficial to our patients. As a result of the toxicity of more effective antiparasitics, shorter regimens of benznidazole or less toxic drugs in preemptive therapy are options that deserve future studies.

Parasitic infections in hematopoietic stem cell transplant recipients

“…1 Screening for Chagas disease through serology is mandatory in patients living in endemic regions, such as Latin America, especially for those born from infected mothers or those that have received multiple blood or derivatives transfusions. 109 The use of insecticides and screening donated blood for disease can reduce the incidence of de novo disease. 52…”

“…There is no routine screening of donors or recipients for T. cruzi in the United States, but those with a history of travel or receiving a blood transfusion in an endemic region should be tested 1 . Screening for Chagas disease through serology is mandatory in patients living in endemic regions, such as Latin America, especially for those born from infected mothers or those that have received multiple blood or derivatives transfusions 109 . The use of insecticides and screening donated blood for disease can reduce the incidence of de novo disease 52 …”