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Decrease in PNH-type Blood Cells after the Cessation of Thrombopoietin Receptor Agonist in a Case of AA-PNH Syndrome
Satoshi Ichikawa1,2, Shunsuke Hatta1, Noriko Fukuhara1
1Department of Hematology, Tohoku University Hospital, Japan.
Abstract:
A 64-year-old male with severe aplastic anemia was initially treated by immunosuppressive therapy, with a partial response. Subsequent thrombopoietin receptor agonist (TPO-RA) therapy resulted in a sustained recovery of cytopenia. After a few years, a gradual increase in the serum lactate dehydrogenase levels was observed, and a massive expansion of paroxysmal nocturnal hemoglobinuria (PNH) clones was established. TPO-RA was discontinued after a transient hemolytic episode of SARS-CoV-2 infection. A follow-up analysis revealed a decrease in the number of PNH clones. Although his blood counts declined moderately, they remained stable without transfusion support, suggesting that although PNH clones may expand under TPO-RA treatment, their withdrawal may facilitate regression.
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