Hyperglyceridemia

Overweight and resistance to insulin appear to play pivotal roles in the pathophysiological process. The resulting hyperinsulinemia induces a rise in systemic arterial blood pressure and probably also a hyperglyceridemia associated with an unfavorable LDL/HDL quotient. This combination of risk factors lowers life expectancy and calls for therapeutic intervention. The metabolic syndrome has a high prevalence in industrialized countries, up to 20% of adults are believed to suffer from it. 

Acute pancreatitis is a rare but serious adverse effect of tretinoin. Three cases associated with isotretinoin-induced hyperglyceridemia have previously been described and two cases associated with tretinoin (79,80). 

Uzawa H, Ito Y, Notomi A, et al. 1969. [Hyperglyceridemia resulting from intake of rice oU contaminated with chlorinated biphenyls.] Fukuoka Igaku Zasshi 60 449-454. (Japanese)... 

Glycerol is present at low concentration in serum occasionally, patients have hyperglyceridemia. Endogenous glycerol must be consumed before triacylgly-cerol lipase (EC 3.1.1.3) is measured to avoid falsely increased lipase values. 

The carbohydrate-dependent hyperglyceridemia occurs only after high carbohydrate intake. The fat particles appear to be carried by lipoproteins which, according to the observations by Ahrens et al. (l957), Kuo and Carson (1959), Brown and Page (1960), and Bierman (1963), float at densities characteristic for the VLDL class. In these patients plasma lipolytic activity is normal (Fredrickson et al., 1963). It would thus appear that the hyperlipoproteinemia is due to hepatic overproduc-... 

Furman et al (1964) have reported studies on the metabolism of the HDL protein, labeled with P , in hyperlipemic subjects. In two patients with fat-induced familial hyperchylomicronemia, the plasma half-time values of the labeled product—1.7 and 1.9 days—were about 50% less than the normal values reported by Scanu and Hughes (1962) and Furman et al (1964). In carbohydrate-induced hyperglyceridemia where VLDL predominates, the half-time values of the radioiodinated protein were intermediate between normolipemic subjects and those with fat-induced hyperlipidemia. An association between the injected labeled... 

Lipolytic Activity of Postheparin Plasma in Hyperglyceridemia J. Lipid Res. 4 24-33 (1963) CA 59 3190d... 

K. Ono, and L. L. Davis Lipolytic activity of post-heparin plasma in hyperglyceridemia. 

Chylomicrons were obtained from plasma after fat feeding (Rodbell, M., and D. S. Fredrickson 1959). The controls were patients with familial fat-induced hyperglyceridemia. It is noteworthy that portions of the chylomicrons of controls were also incubated for 18 h at 2°C with chylomicron-free pl a from the other subjects. This produced no difference in the lipid content of their chylomicrons. Source Fredrickson (1966). 

Of the secondary hyperlipidemias those of hypothyroidism and biliary cirrhosis deserve particular attention, since they may show considerable elevation of cholesterol without hyperglyceridemia. In addition, xanthomas may occur in both with long duration. While biliary cirrhosis is characterized by the presence of jaundice, a very low ester cholesterol to free cholesterol ratio, and significant elevation of the phospholipid level, the exclusion of hypothjrroidism is not always as simple and may require appropriate thyroid function tests. 

A classification of EHL, as proposed by Thannhatjser (1950), into juvenile and adult forms — the latter frequently exhibiting mild glycosuria in addition to hyperglyceridemia — cannot be maintained in this strict sense. However, it still aids in consideration of differential diagnosis of EHL, since the endogenous hyperglyceridemias, to be described, are commonly diagnosed in adults. 

Fat-induced hyperlipemia (FIHL), hyperchylomicronemia, type I of Fredrickson and Lees, alimentary hyperglyceridemia]. 

Fig. 2. Exogenous (fat-induced) hyperlipemia. Intake of any of a variety of fats in this boy resulted in progressive hyperglyceridemia. Fat-free (high carbohydrate) diets were associated with rapid fall of plasma glyceride levels toward normal. Glycerides in this study were determined by difference from total lipids. Values are higher as compared with those of other figures...

There is some evidence that exogenous hyperglyceridemia includes more than one entity (Furman and Robinson 1962, Bialkin et al. 1962, Kinsell and Schlierf 1965). The latter have reported a remission in a boy with hyperchylo-micronemia, which occurred about the time of onset of puberty, and after continuous daily administration of relatively large amounts of heparin for more than... 

The term endogenous hyperglyceridemia as used here is not meant to imply that alimentary fat cannot contribute to the hypertriglyceridemia in such cases under appropriate conditions. However, it seems likely that a basic defect in all the S3mdromes to be discussed is associated with some type of abnormality of metabolism of endogenous very low density lipoprotein with regard either to formation (Farquhar et al. 1963) and/or clearing of these particles. Other mechanisms, secondary to this defect, seem to come into play particularly with more severe forms of the syndrome. 

On the basis of our own experience and to some degree that of others, it seems probable that pure carbohydrate-induced hyperglyceridemia is a relatively rare entity, although by no means as rare as pure fat-induced hyperlipemia (hyperchylomicronemia). 

Fig. 3. Pure carbohydrate-induced byperglyce-ridemia (endogenous hyperglyceridemia group 1). Significant hyperglyceridemia was observed in this 47 year old male subject on a high carbohydrate, fat-free diet. Substitution of most of the carbohydrate by fat resulted in progressive fall in plasma glycerides to normal...

That a number of subjects with carbohydrate-induced hyperlipemia will exhibit significant hyperglyceridemia even on low carbohydrate, high fat diets, is already evident from Fig. 6 given by Ahrens et al. in 1961 and from Table 1 of Knittle and Ahrens (1964). Other authors therefore have used the term carbohydrate-accentuated rather than induced to describe such patients. 

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