Familial Hypertriglyceridemia

Excerpt

Familial hypertriglyceridemia (type IV familial dyslipidemia) is a disorder characterized by the overproduction of very low-density lipoproteins (VLDL) from the liver. As a result, the patient will have an excessive number of triglycerides and VLDL on the lipid profile. This disorder typically follows an autosomal dominant inheritance pattern. Clinically, familial hypertriglyceridemia presents in patients with mild to moderate elevations in lab triglyceride concentration. Familial hypertriglyceridemia is typically accompanied by other co-morbidities: obesity, hyperglycemia, and hypertension. Patients with this disorder are often heterozygous for inactivating mutations of the lipoprotein lipase (LPL) gene. While this mutation can alone raise triglyceride levels significantly, the combination of other medications or pathology can further increase serum triglyceride levels to pathologic levels. Significant increases in triglycerides levels can lead to the development of clinical signs and acute pancreatitis.

When discussing familial hypertriglyceridemia, it is pertinent to discuss Fredrickson-Levy and Lee’s (FLL) phenotypes. The described phenotypes include types I, IIa, IIb, III, IV, and V. Type IV familial dyslipidemia is considered familial hypertriglyceridemia and can be distinguished from other types based on the patient’s lipid profile. Typically familial hypertriglyceridemia is differentiated with significantly high triglycerides and low HDL-C levels in comparison to others in the FLL characterization. However, the influence of comorbid conditions that often accompany the pathology can skew a patient’s lipid profile.