[Frameworks of recognition and classification of primary hyperlipidemia]

A both useful and simple classification of primary hyperlipidemias must be at the disposal of all medical doctors, namely general practitioners and cardiologists. The practical classification we have proposed and published since 1971, fulfills this aim. Three main frames of hyperlipidemias are individualized: 1) pure or essential hypercholesterolemia 2) mixed or combined hyperlipidemias 3) major hyperglyceridemia: either exogenous or endogenous. In each of these frames, some clinical specific features, as well as some very simple biologic characteristics allow sometimes an immediate orientation towards some definite varieties of primary hyperlipidemias, now perfectly identified at the level of molecular genetic (tendinosum xanthoma with or without planar xanthomas, palm creases syndrome, tuberous or tubero eruptive xanthomas, etc...). Similarly, occurrence of cardiovascular complications, chiefly coronary, in a rather early age, and with a striking repetition in other members of family, as well of attacks of acute or subacute pancreatitis in other forms, helps considerably for orientation of the diagnosis. For all these reasons, systematic reconstitution of genetic tree on, at least, three generations in absolutely necessary. Prevalence, in various populations, of the genetic origin of these various primary disorders of lipid metabolism is round one out of 500 at the heterozygote state. Even if all the genes candidates are not yet finished to be identified, much of them are now perfectly known, in their localisation on DNA and in their multiple mutations. Possibility of combination of different gene defects can be also met; and more and more are described. This extraordinary and explosive knowledge in this field is now to be described.