Dear Sir,
We would like to make a brief contribution to the interesting article written by Angheben et al., which was recently published in Blood Transfusion1. The authors provide a comprehensive and well-updated review of Chagas disease, focusing on transfusion medicine and the current strategies for preventing disease transmission in non-endemic areas.
In the section of the article dealing with transfusion-transmitted Chagas disease, the authors state that all blood components, except plasma derivatives, are theoretically capable of transmitting the disease, since their storage conditions allow the parasite to survive. Although Angheben et al. also mention that platelets are the blood component most often associated with reported cases of transfusion-related transmission, they do not specify why this is so.
Cancino-Faure et al. investigated the reason why platelets carry such a high risk of transmitting Chagas disease via transfusion and their findings were recently published in the article, “Evidence of meaningful levels of Trypanosoma cruzi in platelet concentrates from seropositive blood donors”2. Using a quantitative real-time polymerase chain reaction, these authors studied the T. cruzi parasite load in peripheral whole blood, platelets and plasma collected from chronic chagasic blood donors through apheresis donations. They reported that 100% of platelet components of all blood donors were positive for T. cruzi DNA, with a parasitic load 5 times higher than in peripheral whole blood, whereas parasite DNA was undetectable in the plasma component. This finding was attributed to the size and specific gravity3 of the trypomastigote form of T. cruzi, which is very similar to that of platelets and leucocytes. Thus, during the whole blood processing to obtain blood components, T. cruzi concentrates in the platelet fraction and leucocytes, rather than in the plasma fraction. The higher parasitic load found in platelet components, compared to plasma and peripheral whole blood, collected from Chagas-infected blood donors would, therefore, explain the higher risk of Chagas disease transmission associated with platelet transfusions.
Apart from this brief comment, we would sincerely like to congratulate the authors for their excellent review on Chagas disease and transfusion medicine.
Footnotes
The Authors declare no conflicts of interest.
References
- 1.Angheben A, Boix L, Buonfrate D, et al. Chagas disease and transfusion medicine: a perspective from non-endemic countries. Blood Transfus. 2015;13:540–50. doi: 10.2450/2015.0040-15. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.Cancino-Faure B, Fisa R, Riera C, et al. Evidence of meaningful levels of Trypanosoma cruzi in platelet concentrates from seropositive blood donors. Transfusion. 2015;55:1249–55. doi: 10.1111/trf.12989. [DOI] [PubMed] [Google Scholar]
- 3.Amato Neto V, Matsubara L, Bustos Lanura PN. [An evaluation of the quantitative buffy coat system (QBC) in the laboratory diagnosis of Trypanosoma cruzi infection: a study in an experimental murine model]. Rev Soc Bras Med Trop. 1996;29:59–61. doi: 10.1590/s0037-86821996000100013. [In Portuguese.] [DOI] [PubMed] [Google Scholar]