[Familial IgM deficiency and type II hyperlipoproteinemia]

It is reported on the common appearance of a hyperlipoproteinaemia type II after Fredrickson and of a selective insufficiency of IgM in a family. The two generations of a family which have been observed since three years show these disturbances in a 42-year-old patient and all his four children. The diminution and the lack of a stimulation of B-cells under antihuman-IgM in the transformation test of lymphocytes refer to an isolated disturbance of the IgM-synthesis. Cellular immune reactions and haematologically cytological findings were normal. A connection between the lack of IgM and hypercholesterolaemia is not excluded, since experimental investigations of Alderson and Green show an influence of cholesterol on the function of the lymphocyte membrane. The necessity of systematic investigations on patients with immune defects and hyperlipoproteinaemias is emphasized for the exclusion of an accidental coincidence.