[A phenocopy of a homocygote Pelger's nuclear anomaly associated with an antibody deficiency (author's transl)].

A case of a boy is reported with an antibody deficiency syndrome type Bruton leading to a phenocopy of a homozygote Pelger's nuclear anomaly at the age of 10 months. The dominant inheritance and the absence of the anomaly in the peripheral blood of the parents and a sister support the presence of a phenocopy of this leukocyte anomaly. The recurrent bacterial infections are probably the cause of this phenocopy, since the substitution with gammaglobulins did not control the severe antibody deficiency syndrome.