Cold Agglutinin Disease with Livedo Reticularis: A Case Report

Abstract

We report a case of livedo reticularis as a presenting sign of Evans syndrome in a 72-year-old male with a history of myelofibrosis status post matched unrelated donor stem cell transplant. The patient was previously diagnosed with cold agglutinin disease (CAD), an autoimmune hemolytic anemia characterized by hemolysis triggered by cold temperatures. He developed a violaceous, net-like, non-blanching rash consistent with livedo reticularis, which improved with warmth and worsened with cold exposure. Laboratory findings confirmed hemolysis and thrombocytopenia, supporting a diagnosis of Evans syndrome, defined by concurrent autoimmune hemolytic anemia and immune thrombocytopenia (ITP). The patient was treated with sutimlimab, a C1s complement inhibitor, followed by rituximab, resulting in resolution of the cutaneous findings. This case highlights the importance of recognizing livedo reticularis as a possible manifestation of systemic autoimmune processes such as CAD and Evans syndrome and underscores the value of targeting the underlying pathology to achieve dermatologic resolution.