2024 Volume 61 Issue 1 Pages 49-55
We retrospectively analyzed the incidence, risk factors, and response to treatment of post-allogeneic hematopoietic cell transplant (HCT) immune-mediated cytopenias (IMC) in 89 patients (103 HCTs) who underwent HCT at age below 20 years, between January 2010 and March 2023. The 2-year cumulative incidence of IMC was 4.8%. Multivariate analysis identified younger age at HCT (below 1 year) as the sole independent and significant risk factor for the development of post-HCT IMC (P=0.039). Four patients, all with non-malignant diseases, developed IMCs (2 cases of autoimmune hemolytic anemia and 2 of immune thrombocytopenia) at a median of 95 days post-HCT (range, 56–432 days). These patients had undergone HCT from unrelated donors utilizing a reduced-intensity conditioning regimen. Rituximab in combination with mTOR inhibitor everolimus or anti-CD38 monoclonal antibody daratumumab was effective for two patients who were refractory for prednisolone and intravenous immunoglobulin. All patients obtained complete responses; however, one patient experienced a recurrence of IMC. Nationwide surveys are essential to gain insights into the prevalence of post-HCT IMC in Japan.
