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Detection of Residual Donor Erythroid Progenitor Cells after Hematopoietic Stem Cell Transplantation for Patients with Hemoglobinopathies
Published on: September 6, 2017
Neither COVID-19, nor cryopreservation, prevented allogeneic product infusion: A report from the National Marrow
Nosha Farhadfar1, Jeni Newman2, Jennifer Novakovich2
1University of Florida, Gainesville, FL, United States.
Insights
The COVID-19 pandemic impacted stem cell collection, with cryopreservation becoming standard. Transplantation from SARS-CoV-2-positive donors proved safe, ensuring patient access to lifesaving stem cell grafts.
Area of Science:
- Hematology
- Immunology
- Infectious Diseases
Background:
- The COVID-19 pandemic created significant challenges for stem cell donor registries.
- Rapid strategies were implemented by the National Marrow Donor Registry (NMDP) and partners to mitigate these challenges.
Purpose of the Study:
- To report the impact of the COVID-19 pandemic on stem cell graft collection and utilization.
- To assess short-term outcomes for patients receiving stem cell products from COVID-19-positive donors.
Main Methods:
- Comparative analysis of NMDP data from early (March-May 2020) and later (March-May 2021) pandemic phases.
- Odds ratios calculated to assess the pandemic's impact on graft source requests by transplant centers (TCs).
- Kruskal-Wallis test used to evaluate effects on disease indication, search volume, and non-infused products.
Main Results:
- Initial decline in donor searches, followed by recovery to pre-pandemic levels.
- Cryopreservation became common due to restrictions, with increased requests for fresh bone marrow grafts later.
- Transplant centers increased acceptance of cryopreservation, reducing non-infused products.
- No short-term adverse outcomes observed in patients receiving grafts from SARS-CoV-2-positive donors.
Conclusions:
- Despite pandemic challenges, the NMDP and TCs ensured patient access to essential stem cell grafts.
- Transplantation from donors with COVID-19 is feasible and safe, based on limited data.
Background:
The Coronavirus Disease 2019 (COVID-19) pandemic in early 2020 has resulted in an unprecedented level of uncertainty and challenge for the stem cell donor registries. To address these challenges, rapid strategies were implemented by the National Marrow Donor Registry (NMDP) and its network partners. Herein, we aim to report the impact of the COVID-19 pandemic on the collection, utilization of grafts, and short-term outcomes of patients who received stem cell products from COVID-19-positive donors.
Methods:
NMDP data during the early phase (1 March 2020 through 1 May 2020) of the pandemic were compared to the later phase (1 March 2021 through 1 May 2021). Odds ratios were calculated to determine the impact of the pandemic on graft sources requested by transplant centers (TCs). The Kruskal-Wallis test was used to test the effect of the pandemic on the disease indication, volume of searches, and number of products not infused.
Results:
Although there was an initial decline in overall donor searches during the early phase of the pandemic, these numbers increased reaching pre-pandemic levels during the later phase. Urgent malignant diseases remained the most common indication for transplant in 2021. The pandemic necessitated cryopreservation of stem cell products due to transportation restrictions as well as clinical uncertainties in managing the virus. Cryopreserved grafts remained the most common requested grafts throughout the pandemic. In the later phase of the pandemic, the total numbers of requests for fresh grafts increased, mostly due to the increase in requests for fresh bone marrow (BM) grafts. As the pandemic continued, TCs became more accepting of cryopreservation, resulting in a reduction in the number of products not infused. Lastly, no short-term deleterious outcomes were noted among the patients who had stem cell products infused from a SARS-CoV-2-positive donor.
Conclusion:
Throughout the pandemic, the NMDP and TCs worked tirelessly to ensure that patients would receive lifesaving grafts when needed. The data reported here, although limited by small numbers, illustrate that transplantation from donors with COVID-19 is feasible and safe.

