Adult-onset severe paroxysmal cold hemoglobinuria after COVID-19 successfully treated with sutimlimab.

Paroxysmal cold hemoglobinuria (PCH) is a form of cold autoimmune hemolytic anemia characterized by the presence of the Donath-Landsteiner antibody, which triggers complement-mediated intravascular hemolysis when the body temperature changes from cold to warm. PCH occurs primarily in children as a rare, self-limiting disease following viral infections. In contrast, adult-onset PCH is very rare and associated with a diverse range of underlying conditions, which complicates its management and treatment. We describe a case of adult-onset PCH following COVID-19, effectively managed with a single dose of sutimlimab, a selective classical complement pathway inhibitor. This intervention was performed during a life-threatening hemolytic crisis, at a time requiring swift decision-making when specific tests to differentiate from other hemolytic anemias were not readily available. This case illustrates the potential of using a single dose of sutimlimab to manage life-threatening hemolytic crises in PCH, highlighting the significance of inhibiting the classical complement pathway.

Successful allogeneic hematopoietic stem cell transplantation in a patient with type I CD36 deficiency: a case study and literature review.

BACKGROUND: CD36-deficient individuals may produce anti-CD36 antibodies through antigenic exposure to CD36, in situations including blood transfusions. Therefore, allogeneic hematopoietic stem cell transplantation (HSCT) from CD36-positive donors to CD36-negative patients remains a challenge. CASE REPORT: A 64-year-old man with acute myeloid leukemia became refractory to platelet transfusions during chemotherapy. Anti-CD36 antibodies without anti-HLA antibodies were detected in serum, and the absence of CD36 expression on platelets and monocytes confirmed type I CD36 deficiency. The patient achieved complete remission, and received maintenance therapy with CD36-negative platelet transfusions. However, he relapsed soon afterward, and thus underwent peripheral blood stem cell transplantation (PBSCT) from a CD36-positive unrelated donor. The anti-CD36 antibody titer had decreased before the transplant, and the PBSCT-course was uneventful. The patient has been well without any complications associated with CD36 status mismatch. DISCUSSION: The few reports of allogeneic HSCT in patients with CD36 deficiency have suggested that anti-CD36 antibodies could be involved in several post-transplant complications, such as delayed platelet recovery, transfusion refractoriness, and transfusion-related acute lung injury. Our present case confirmed that stem cell transplantation from CD36-positive donors to negative patients is feasible, when it includes careful prior assessment of anti-CD36 antibody titers and interventions to attenuate them.

Eosinophilic Fasciitis with Hypereosinophilia as the Initial Clinical Manifestation of Peripheral T-Cell Lymphoma, Not Otherwise Specified.

A 58-year-old man presented with painful edema of the extremities, and a diagnosis of eosinophilic fasciitis (EF) was confirmed. He also met the criteria for hypereosinophilic syndrome (HES), but there were no findings suggestive of malignancies or hematologic neoplasms despite a close examination. He was started on steroid therapy but subsequently developed severe liver dysfunction, hemophagocytic lymphohistiocytosis, hepatosplenomegaly, and renal involvement. The diagnosis of peripheral T-cell lymphoma, not otherwise specified was finally established by a bone marrow reexamination and liver biopsy. In cases of eosinophilia, EF, and/or HES, it is important to suspect an intrinsic abnormality, including potential T-cell lymphoma.