Atherosclerosis
George Feuer, Felix A. de la Iglesia in Molecular Biochemistry of Human Disease, 2020
Chylomicrons are present in the plasma in excessive amounts but the lipoprotein bands are normal in Type I hyperlipoproteinemia or familial lipoprotein lipase deficiency, due to molecular defects of lipoprotein lipase activity.464 This disorder is associated with removal of exogenous or dietary fat from the plasma. The elevated triglyceride levels are probably due to the inability to clear chylomicrons resulting from low plasma postheparin lipoprotein lipase activity (Figure 34). The activity of other lipases is apparently normal. This condition may be corrected therefore by reducing the dietary intake of fat. High carbohydrate diets can also increase VLDL due to conversion of carbohydrate to lipids in the liver.
Lipoprotein lipase deficiency/type I hyperlipoproteinemia
William L. Nyhan, Georg F. Hoffmann, Aida I. Al-Aqeel, Bruce A. Barshop in Atlas of Inherited Metabolic Diseases, 2020
Management of the acute abdominal pain requires vigilance about the diagnosis of pancreatitis and recognition that amylase values may be normal. The treatment of pancreatitis should follow the usual conservative regimen, with the additional precept that fat should be eliminated. In a neonate with chylomicronemia and congestive cardiac failure, triglyceride levels of 38,000 mg/dL were reduced to normal by plasmapheresis, and cardiac function became normal [82]. The treatment of apoC-II deficiency should generally be the same as that of lipoprotein lipase deficiency. An episode of pancreatitis may be successfully treated in apoC-II deficiency by the infusion of normal human plasma.
Features of Lipid Metabolism in Diabetes Mellitus and Ischemic Heart Disease
E.I. Sokolov in Obesity and Diabetes Mellitus, 2020
After the taking of food, chylomicrons are detected in the intestine. They form in the cells of the mucous membrane of the small intestine and pass into the lymphatic tracts. After getting into the blood channel, the chylomicrons experience numerous changes, in particular phospholipids are detached or are exchanged for other lipid fractions. The triglycerides of the chylomicrons are exogenic fats and contain the fats from food. The duration and level of increased chylomicronemia depend on the amount and composition of the introduced fats, and also on the amount of carbohydrates in the food. If the latter are taken together with fats, the chylomicron level after a lipid toad diminishes.
Management of asymptomatic severe hypertriglyceridemia
Published in Baylor University Medical Center Proceedings, 2022
Nathalie V. Scherer, Dipesh Bista
Chylomicronemia syndrome is defined as TG >1000 mg/dL with additional manifestations, such as eruptive xanthelasmas or lipemia retinalis.8 Our patient met these criteria. A variety of underlying pathophysiological changes can give rise to chylomicronemia syndrome, but the precise etiology in our patient is unclear. The most common cause of chylomicronemia syndrome is familial hypertriglyceridemia, an autosomal dominant trait, but the patient had no relevant family history, and genetic testing was not indicated.8 A variety of other factors can aid in developing this syndrome, such as uncontrolled diabetes mellitus, a diet high in fats, and pregnancy.3 Given that this patient had given birth several months prior, presented with hyperosmolar hyperglycemia syndrome, and had a body mass index ≥25 kg/m2, it is likely that her chylomicronemia syndrome developed from a combination of genetic predisposition and some modifiable risk factors.
Safety and efficacy of therapies for chylomicronemia
Published in Expert Review of Clinical Pharmacology, 2022
Isabel Shamsudeen, Robert A. Hegele
Chylomicronemia syndrome refers to the presence of >1 associated clinical feature in patients with primary chylomicronemia [1]. Common clinical features include failure to thrive, nausea and vomiting, abdominal pain, eruptive xanthomas on the trunk and limbs, lipemia retinalis, and hepatosplenomegaly [4,19,20]. Less common clinical features include anemia, intestinal bleeding, diarrhea, seizures, and encephalopathy [7]. FCS develops in childhood, adolescence, or in early adulthood [2]. In contrast, MCS tends to develop later in life, usually in adulthood, often in the context of a secondary medical condition or medication [2]. Therefore, patients with MCS more often present with poorly controlled or undiagnosed diabetes mellitus, obesity, excessive alcohol intake, poor diet, chronic kidney disease, nephrotic syndrome, and hypothyroidism, all of which are associated with HTG [2]. Clinical features of MCS are similar to those of FCS, but without the pediatric features such as failure to thrive [2]. Moreover, patients with FCS tend to have normal or low weight, whereas patients with MCS have a high prevalence of overweight and obesity [2].
Pharmacological treatment options for severe hypertriglyceridemia and familial chylomicronemia syndrome
Published in Expert Review of Clinical Pharmacology, 2018
Rabia Chaudhry, Adie Viljoen, Anthony S. Wierzbicki
It is more logical to define hypertriglyceridemia syndromes by their genetic etiology. Chylomicronemia syndrome is mostly caused by five genes affecting proteins relevant to the LPL metabolic pathway. Patients having mutations in two relevant alleles are homozygous or compound heterozygous and should be defined as having familial chylomicronemia syndrome (FCS) and strictly only the subset with mutations in LPL have lipoprotein lipase deficiency (LPLD) [4]. Many patients have reduced LPL activity, but LPL activity can be close to normal in patients with apoC2 deficiency or those who are dual gene heterozygotes [4]. Patients with single mutations are simple heterozygotes and may have reduced LPL activity and have partial LPL deficiency if the primary mutation is in LPL. However, many patients heterozygous for LPL pathway mutations are asymptomatic and have normal lipid profiles so the etiology of hypertriglyceridemia in such patients is likely to represent a more complex interaction of genes and environment. A further group of patients have severe polygenic TG elevations caused by variants at multiple genes with effects on TG metabolism and also can express a phenotype of partial LPL deficiency [5,6].
Related Knowledge Centers
- Diabetes
- Lipoprotein Lipase
- Pancreas
- Xanthoma
- Liver
- Pancreatitis
- Triglyceride
- Genetic Disorder
- Dominance
- Fat