Evidence of meaningful levels of Trypanosoma cruzi in platelet concentrates from seropositive blood donors

Abstract

BACKGROUND According to the reported cases of transfusion‐acquired Trypanosoma cruzi infection, the risk of T. cruzi transfusion transmission appears to be higher with platelet (PLT) products than with other blood components. The aim of this study was to investigate by quantitative real‐time polymerase chain reaction (qPCR) the parasitic load detected in leukoreduced plasma and PLT concentrates collected by apheresis from seropositive T. cruzi blood donors and compare them with peripheral whole blood (WB). STUDY DESIGN AND METHODS During 2011 to 2013, a prospective study was carried out in a group of blood donors originating from Chagas‐endemic areas but who are now living on the island of Majorca, Spain. Leukoreduced plasma and PLT concentrates were collected by apheresis from seropositive blood donors with detectable parasitemias in peripheral WB. RESULTS Seropositivity was found in 23 of 1201 donors studied (1.9%), and T. cruzi DNA with less than 1 parasite equivalent/mL was detected in peripheral WB in 60.86% (14 of 23) of these. The study in blood components obtained by apheresis from these donors showed that T. cruzi DNA with a mean ± SD parasitic load of 5.33 ± 6.12 parasite equivalents/mL was detected in 100% of the PLT concentrate samples. Parasite DNA was undetectable in the extract taken from plasma collected from donors with a positive qPCR in peripheral WB. CONCLUSION The higher parasitic load found in PLT concentrates compared to plasma and peripheral WB would explain the higher transfusion transmission risk of Chagas disease associated with PLT transfusions described in the reported cases of transfusion‐acquired T. cruzi infection.

Our experience in riboflavin and ultraviolet light pathogen reduction technology for platelets: from platelet production to patient care

“…Despite progress in donor screening and laboratory testing, a small risk of bacterial, viral, or protozoal contamination of PLTs persists. There is also a continuous risk from newly emerging blood transfusion–transmitted infectious agents .…”

“…Over the past decade there have been five definitive cases of transfusion‐transmitted T. cruzi in Spain, all related to PLT transfusions, prepared from either buffy coats or apheresis, collected from Latin American donors with imported Chagas disease . Our group has also shown that PLT concentrates collected by apheresis from seropositive T. cruzi blood donors from Latin America presented a higher parasitic load compared to plasma and whole blood (WB) . We found that the highest T. cruzi concentration in experimentally infected WB units was in the buffy coat fraction, which would explain the high risk of Chagas disease transmission associated with PLT transfusions described in the literature .…”

Prevalence of Trypanosoma Cruzi antibodies in blood donors from the Sao Paulo State, Brazil, between 2012 and 2014

“…The possibility of transfusion-transmitted infection depends on risk factors such as the amount of transfused blood, parasite strain, presence of parasitemia by the time of donation, immune status of the recipient, and sensibility of the used diagnostic tests [4]. The highest transfusion transmission risk has been observed for platelet concentrates in comparison to plasma and whole blood due to the higher platelet parasitic load [6]. Fortunately, only a small proportion of individuals infected with T. cruzi through blood transfusion develop clinically overt disease [7].…”

Chronic Chagas Disease Diagnosis: A Comparative Performance of Commercial Enzyme Immunoassay Tests

“…More recent work has revealed that 1.91% of the blood donors screened for Chagas disease living on the island of Majorca, Spain, and coming from Chagas-endemic areas were seropositive, particularly from Argentina and Bolivia. 10 Since no test has been found to be sufficiently sensitive and specific to be designated the sole screening assay for Chagas disease, World Health Organization advises that, to ensure a reliable diagnosis, screening must be carried out by at least two assays based on distinct techniques and used concomitantly. In Brazil, the Health Ministry recommends the use of a test with high Se (with total antigen or semi-purified fractions of the parasite) in combination with a high specificity (Sp) test in parallel (using T. cruzi-specific, recombinant antigens).…”