[Prevalence and seasonal variations of irregular alloantibodies, especially the anti-Lewis]

In order to determine the efficiency of a technical modification of the screening procedure for irregular antibodies, the authors compare results obtained upon two patients' groups. Group I: 47.638 tests done by classical technics (462 antibodies: 105 anti-Lewis and 357 non Lewis antibodies). Group II: 22.437 tests done by the new method (563 antibodies: 262 anti-Lewis and 261 non Lewis antibodies). This new screening procedure is more efficient than classical technics and put in a prominent position the actual frequency of Lewis antibodies. The relationship between Lewis antibodies, ABO blood groups and sex are discussed. It seems to be an accumulation of Lewis antibodies within group A and AB. The frequency of group O is decreased among patients with Lewis antibodies. There is no modification of the frequency of B blood group. The authors suggest that a quantitative relationship exists between ABO phenotype, secretor status and the occurrence of Lewis antibodies. There is no sex difference in the frequency of Lewis antibodies. A seasonal variation in the frequency of irregular antibodies is reported, with a maximum into hivernal months.