Plasma lipids in extra hepatic biliary obstruction

Area of Science:

• Biochemistry
• Clinical Medicine
• Lipid Metabolism

Background:

• Extra hepatic biliary obstruction (EHO) is associated with altered plasma lipid profiles.
• Previous studies suggested hypertriglyceridemia in EHO, but its consistency and significance required further investigation.

Purpose of the Study:

• To investigate the extent and consistency of hypertriglyceridemia in patients with EHO.
• To compare plasma lipid and lipoprotein changes in EHO patients before and after surgical relief of obstruction.
• To differentiate EHO-associated hypertriglyceridemia from endogenous (type IV) hypertriglyceridemia.

Main Methods:

• Analysis of plasma lipids and lipoproteins in 15 patients with EHO and 23 controls.
• Comparison of lipid profiles before and after surgical intervention for EHO.
• Electrophoretic analysis of lipoproteins and assessment of cold aggregation tests.

Main Results:

• Patients with EHO exhibited increased total cholesterol (unesterified fraction), phospholipids, and a marked, persistent elevation in triglycerides.
• Triglyceride levels in EHO were comparable in magnitude to cholesterol and phospholipid increases and normalized post-obstruction relief.
• EHO-associated hypertriglyceridemia presented with clear serum, negative cold aggregation, and a broad beta fraction, differing from type IV hypertriglyceridemia.
• Lipoprotein-X was detected in EHO patients and persisted even after other lipid parameters normalized.

Conclusions:

• Extra hepatic biliary obstruction consistently causes significant hypertriglyceridemia, characterized by specific lipoprotein changes.
• The hypertriglyceridemia in EHO is reversible upon relief of obstruction, unlike certain other lipid abnormalities.
• Lipoprotein-X is a persistent marker associated with EHO, even when other lipid parameters return to normal.