P83 | Cold hands: when the warm is better

Premises: Cold agglutinin (CA) disease is a rare autoimmune hemolytic anemia in which the antibodies for erythrocyte surface antigens are activated by low temperatures, causing agglutination of red blood cells (RBC). Autoantibodies may be idiopathic or secondary to infection, malignancy, and other autoimmune diseases. It’s under recognized with diagnosis delay. Case report: A 76-year-old man with hypertension, presented with fatigue, lower extremities pain and dyspnea. Physical examination revealed pale skin and jaundice, no bruises, no hepatosplenomegaly, or lymphadenopathy. Lab test showed haemoglobin (hb) 6,6 g/dL, MCV 111 fl, normal white cell and platelets, high reticulocytes, bilirubin, and lactate dehydrogenase, low haptoglobin. A peripheral blood smear showed anisocytosis and poikilocytosis, RBC agglutination. DAT was positive for C3d with CA. Bone marrow study demonstrated an infiltration of low-grade B lymphoma. The patient has been treated with warmed RBC and kept in warm environment. With progressive hb increase and normal hemolysis values, we decided for follow up, without other treatment, like rituximab. Re-evaluating previous lab tests, it was noted that for some years reversible RBC agglutination was reported. Conclusions: Cold avoidance and warmed transfusions are first line therapy for CA hemolysis. CA interferes in lab tests. Informing the laboratory and ensuring the proper temperature conditions will lead to accurate results. It would be desirable to alert the physician of the presence of agglutination to prescribe the appropriate investigations.