Cold Agglutinin Disease

The goal of this observational study is to characterize the diagnostic and therapeutic management of autoimmune cytopenias including autoimmune hemolytic anemia, immune thrombocytopenia, and chronic idiopathic/autoimmune neutropenia. The main aims to answer are: * evaluation of traditional and novel diagnostic tools including immunohematology, cytokine essays, bone marrow studies, molecular findings, and fecal microbiome. * evaluation of type and sequence of the therapies administered, the response rates, and the adverse events. * evaluation of clinical and laboratory (immunologic, molecular, and morphologic) predictors of outcome. * evolution of autoimmune cytopenias into myelodysplastic syndromes. * a subgroup of patients with myelodysplastic syndromes will be included to evaluate the presence of immunologic events, autoimmune activation, and red cell metabolism. Participants will receive a clinical/laboratory diagnostic workup as per current clinical practice. Furthermore They will be sampled at baseline (peripheral blood and feces for microbiome) and followed up for at least 3 years to evaluate their clinical course, therapeutic management and outcome.