Condensation test

This test assists in the diagnosis of Mycoplasma pneumoniae (primary atypical pneumonia). Its agglutinin generally begins to increase in the second week after onset. After suffering from Mycoplasma pneumonia, a substance called cold agglutinin appears in the patient's serum, which is an antibody to the red blood cell membrane antigen. This kind of antibody can combine with the patient's own red blood cells or O-type human red blood cells in a zero-degree Celsius environment to cause an antigen-antibody reaction, cause agglutination of red blood cells, and even cause cell lysis, so-called hemolysis.