These data comprise 1,231,024 routine tests carried out over a 5-year period on
voluntary blood donors. The percentage of positive results on the machines varies from 1 to
3% of the total number of samples tested. Antibodies identified either by manual or automated
techniques make up 15-20% of the positive screening reactions. Rhesus, Lewis and P systems
prevail, whilst Duffy, Kidd and Lutheran systems are absent.
This screening has three main advantages: the supply of plasma for our production of test
sera, or therapeutic immunoglobulins; protection of the recipient; partial information on the
donor’s immunohaematological state, especially for the risk of giving him incompatible blood
sometimes in the future.