COVID-19 convalescent plasma (CCP) from men who have recovered from the illness may contain HLA antibodies (HLA-Ab), a risk factor for transfusion-related acute lung injury (TRALI), according to a new report. In the United States, COVID-19 convalescent plasma (CCP) is now a treatment option in patients with severe or life-threatening SARS-CoV-2 infection. Donor HLA-Ab are a chief cause of TRALI, which is one of the top causes of transfusion-related mortality. They are usually caused by prior pregnancies, transfusions or transplantations, but viral infections can also trigger their formation, Drs. Justin E. Juskewitch, James Stubbs and Manish Gandhi of the Mayo Clinic in Rochester, Minnesota, note in a letter to the editor of Mayo Clinic Proceedings. During April and July, 157 unique CCP donors underwent HLA-Ab screening and 16 CCP donors (10.1%) were deferred for a positive HLA-Ab screen. Among 69 unique male CCP donors, five screened positive for HLA-Ab (7.2%), the authors report. "None of these five male CCP donors had a history of transfusion, transplantation, or pregnancy. This male HLA-Ab screening positivity rate was significantly higher than expected for this donor population (P<0.0001; chi-square test). In all, male donors represented 31% of all CCP donors who have screened positive for HLA-Ab (5 of 16)," they note in their letter. If confirmed in other studies, these findings "could have significant implications on CCP donor screening to help mitigate the risk of TRALI especially now that CCP use has broadened to any hospitalized COVID-19 patient under an FDA Emergency Use Authorization," they conclude. In a phone interview with Reuters Health, Dr. Juskewitch said these results are "based solely on our experience so far at our blood-donor center in Rochester, Minnesota. And it really does leave one major question, which is, is this just a local phenomenon that we're just seeing with our convalescent plasma donors or is this more indicative of something more widespread across all donors?" "We meant this letter to be like a warning flag out to the transfusion community," he added. "We're really hoping this letter would spur other blood collectors and providers to start looking into this phenomenon in their own donor populations to see if it really is across all donor populations or just something with ours. That was the whole purpose." The Mayo Clinic has implemented universal screening of all male and female CCP donors for HLA-Ab. —Megan Brooks Source
