SARS-COV-2 screening in allogeneic hematopoietic stem cell donors: Implications for the evaluation process and eligibility

Abstract

Introduction Soon after the onset of the SARS-CoV-2 pandemic, viral screening by nasopharyngeal swab became mandatory for allogeneic hematopoietic stem cell (HSC) donor eligibility. Methods We described our monocenter experience with allogeneic HSC donors from February 1 to the October 31, 2020 to verify whether the introduction of SARS-CoV-2 screening altered the donor eligibility and/or entailed a prolongation of the evaluation process. Results A total of 21 allogeneic HSC donors were screened during the above-mentioned period upon request by the local transplant physicians or by the Italian Bone Marrow Donor Registry; among the HSC donors (n = 17) who completed the eligibility process and further received the nasopharyngeal swab, all but one were negative for the presence of SARS-CoV-2. The donor remained asymptomatic for the whole duration of the infection, which lasted six weeks. However, he was temporarily excluded from donation. The median duration of the evaluation process was not significantly different, compared to the same period of 2019 ( p -value = 0.11). Conclusion The mandatory SARS-CoV-2 screening in allogeneic HSC donors allowed for the detection of 6% positivity in this monocenter series over a 9-month period. Despite the inconvenience of this unexpected non-eligibility, the exclusion of a SARS-CoV-2 positive donor represented an important safety measure for the donor, with respect to a new and still partially unknown virus. The screening did not alter the length of the donor evaluation and thus, did not cause a delay in the eligibility process.

Is SARS-CoV-2 screening still necessary before hematopoietic stem cell donation? Observations from a single center and review of the literature

“…As a consequence, SARS-CoV-2-positive donors are not considered eligible for donation and therefore postponed, or a risk-benefit ratio must be balanced to decide to proceed anyway to HSC collection. We recently reported our experience during the first wave of Covid-19 when we found a 6% (1 out of 17 donors) prevalence among stem cell donors [1] ; other groupd reported cases of HSC collections from positive donors, who had a regular clinical course after donation [2] , [3] , [4] and, importantly, did not transmit the infection by the means of HSC donation, as also is expected with blood donations [5] , [6] .…”