Paroxysmal Cold Hemoglobinuria: Role of Hospital Transfusion Medicine and Immunohematology Department in the Diagnosis

Background: Paroxysmal cold hemoglobinuria (PCH), an autoimmune hemolytic anaemia caused due to polyclonal IgG anti-P autoantibody binding to red blood cell surface antigens and is characterized by hemoglobinuria, typically after exposure to cold temperatures. Case Presentation: An 84-year-old female patient started developing breathing difficulty off and on with generalised weakness and loss of appetite. There was continuous fall in hemoglobin and continuous evidence of intravascular hemolysis since last 15 days. After ruling out many common diagnosis, Donath – Landsteiner Test was done which showed Immunoglobulin G, IgG, antibodies, appearing at 4oC and hemolysing at 37oC in the presence of complement. Peripheral smear showed anisopoikilocytosis and spherocytosis. Reticulocyte count was on the lower side (0.5%). Forward and reverse blood grouping showed no group discrepancy. Direct antiglobulin test (Direct Coombs test, DAT) was positive with the monoclonal C3 antisera and negative with the monoclonal anti-IgG. ICT, Indirect Coombs Test, was negative. Syphilis was tested negative by Treponema pallidum hemagglutination assay (TPHA). Results: Patient was diagnosed as a case of PCH based on the test results. Conclusions: Detecting blood antibodies, auto, allo, cold or warm, is important. The role of transfusion medicine laboratory in the diagnosis of patient PCH is emphasised.