Cold hemolysis test

Paroxysmal cold hemoglobinuria (PCH) is an autoimmune hemolytic syndrome. Patients produce a cold-reactive antibody (DL antibody), which belongs to IgG, and cannot firmly bind red blood cells at 37 ° C. When the temperature drops below 20 ° C, DL antibodies can bind to the surface of red blood cells if complement is present. When the temperature increased to 37 ° C, hemolysis occurred due to a series of complements participating in the reaction, forming voids in the red blood cell membrane.