Cold hemagglutinin | DNB Based MCQ

NIME Next Batch PGI Quest in Delhi from 10 August to 20 August

Cold hemagglutinin is associated with 

A. Ig M antibody 
B. Ig G antibody 
C. Ig A antibody 
D. Donath Landsteiner Ab

Ans. A. (1gM antibody)

•Cold-reactive antibodies exhibits increased titre and red cell binding activity as the temperature approaches 0°C •Two types of cold-reactive autoantibodies to RBCs are recognized: cold agglutinins and cold hemolysis

• Cold agglutinins of cold agglutinin disease (CAD) are of 1gM type usually directed at the red cell I antigen

• In 1903, Landsteiner was the first to describe the presence of cold agglutinins in the blood, which were capable of inducing hemogglatination at 4°C and not at 37°C and were therefor termed cold agglutinins

•Cold hemolysis seen in Paroxysmal cold hemoglobinuria (PCH) are of IgG type usually directed at red cell ‘p’. antigen and are called Donath Landsteiner antibodies.