Essential hyperlipemia

The normal ovarian and adrenal lipid is intracellular, but there is another important situation in which a lipoid mesophase may be present more or less normally, entirely outside cells. This is in the plasma (39), in the low density /3-lipoprotein fraction (Sf 12 to 20). In health, this fraction is low or absent until adult life. It begins to increase in males from about the age of 20 onward in females, it remains low until the menopause, after which it increases rapidly as in males. It can be produced experimentally in rabbits, dogs, fowls, and some other animals by feeding cholesterol. Analogous to this is the pathological increase seen in humans with certain renal and metabolic disorders, especially in diabetes mellitus and in hereditary or essential hyperlipemia, where there is an increase in several fatty components in the blood, with abnormal deposition of fat in various tissues. 

Fatty Acid Composition of Serum Lipids in Essential Hyperlipemia and in Hypocholesterolemic Xanthomatosis... 

Allerton, S. E. Ultracentrifugal studies on proteins. Ph. D. Thesis Harvard University 1962. Angerwall, G., P. Bjorntorp, and B. Hood Studies on the clearing phenomenon in essential hyperlipemia. Acta med. scand. 172, 5—14 (1962). 

Figure 1. Fractionation of plasma lipids in a case of essential hyperlipemia by silicic acid column chromatography according to Hirsch and Ahrens (1958) — cholesterol esters, TG = triglycerides,...

As regards individual phospholipids, Nothman and Proger (1962, 1965) have reported a 2- to 3-fold increase of the absolute and relative concentration of phosphatidyl ethanolamine and phosphatidyl serine. A discussion of these findings has been given in the chapter on essential hyperlipemia on page 468 and will not be repeated here. Suffice it to say that a recent study by Wagener and Fro sen (1964) did not confirm this finding. 

In pure EFH, plasma triglycerides are normal or only slightly elevated, in accordance with the low triglyceride concentration in beta-lipoproteins. When high triglyceride levels are observed associated with features of EFH rather than of essential hyperlipemia, one is probably dealing with a separate syndrome (see page 460). 

Comparative studies in patients with EFH and essential hyperlipemia, on the effect of CPIB and dextrothyroxine on low and very low density lipoproteins respectively, were performed by Strisower and Strisower (1964). CPIB lowered very low density lipoproteins (and thus triglycerides) more than dextrothyroxine, but the latter drug was superior to CPIB as regards the depressing effect on serum beta-lipoproteins and thus on cholesterol (see also page 434). 

The mode of action of the drug has not been clarified. Some relevant theories have been discussed in the chapter on essential hyperlipemias. 

Amatuzio, D. S., F. Grande, and S. Wade Effect of glucagon on the serum lipids in essential hyperlipemia and in hypercholesterolemia. Metabolism 11, 1240 (1962). 

Ideally, diseases are classified on the basis of etiologic factors. It is the consensus of students in the field of lipid metabolism that such a goal has not been reached with regard to the various disorders of lipid metabolism and the term essential hyperlipemia reflects this ignorance. However, significant advances from a purely... 

Following reports of triglyceride elevation in normal subjects on high carbo-hjrdrate diets, Ahrens et al. (1961) proposed that essential hyperlipemia may... 

In reviewing the literature, it seems probable that the majority of cases of essential hyperlipemia which have been reported fall into this category. It should again be emphasized that this group probably is not homogeneous and may eventually be separated into several subsyndromes. 

It is likely that cases who have been described in the past as essential hyperlipemia on the basis of lipemic plasma and who exhibited tendon xanthomas belong in this group. Cases of essential hypercholesterolemia with and without plasma turbidity, whose plasma triglycerides exceed the levels expected from increased /3-lipoproteins, would qualify for membership. Such cases can be found in reports by Lever et al. (1954), Adlersberg (1955), Furman et al. (1961), Kuo and Basset (1963) and others. 

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