Kidney Transplantation in Patients at Risk for Chagas Reactivation or Transmission: A Real-World Cohort Study.

BACKGROUND: Kidney transplant recipients in endemic areas are at risk of Trypanosoma cruzi reactivation or donor-derived infection. METHODS: We performed a retrospective study of all kidney transplants conducted between January 2018 and October 2023. Patients at risk for Chagas disease were defined as those with a seropositive donor and seronegative recipient (D+/R-), a seronegative donor and seropositive recipient (D-/R+), or a seropositive donor and a seropositive recipient (D+/R+). Screening was based on serology. Posttransplant monitoring included parasitemia detection using direct microscopy (Strout method) and quantitative polymerase chain reaction (qPCR). Outcomes included Chagas reactivation or primary infection, parasitemia dynamics, and clinical outcomes. Data on immunosuppression, rejection treatment, and graft and patient survival were also collected. RESULTS: Among 954 kidney transplant recipients, 48 (5%) were identified as being at risk. Two patients were excluded (follow-up at another center, n = 1; immediate graft loss due to hyperacute rejection, n = 1). qPCR detected parasitemia in 3/17 (18%) seropositive recipients and 2/28 (7%) recipients of organs from seropositive donors. (One of these two patients was non-adherent to monitoring, and developed parasitemia detectable by the Strout method and clinical disease). Antitrypanosomal therapy was initiated in five patients (benznidazole, n = 4; nifurtimox, n = 1), including three R+ and two D+/R- cases, all achieving molecular clearance. During follow-up (median: 29.77 months (range: 8.49-80.7), no patient developed further clinical manifestations after treatment. CONCLUSIONS: Molecular monitoring allows early detection of Chagas reactivation or transmission after kidney transplantation. Preemptive treatment triggered by parasitemia appears effective in preventing progression to clinical disease, with favorable long-term outcomes.