OVERVIEW
Hyperlipoproteinemia type I (exogenous hypertriacylglycerolemia; familial fat-induced lipemia; hypercryptolemia) is a relatively rare inherited disorder caused by dysfunction of lipoprotein lipase or lipase-interacting protein apo-II, which results in decreased clearance of celiac and VLDL, and triacylglycerol from the blood.
Etiology
Hyperlipoproteinemia type I is a rare autosomal recessive disorder seen mainly in young children with abdominal pain. Hyperlipoproteinemia type I is triggered by fats in food and causes hyperchymotrypsinemia due to lipase deficiency with deposition of lipoproteins in the viscera and skin.
Symptoms
Children and young adults present with the abdominal pain of pancreatitis, a pinkish-yellowish rash of fat deposits (xanthomas), especially in areas of compression and on the surface of the extensor muscles; retinal plaques and hepatosplenomegaly may also be present. A fatty diet may exacerbate the signs and symptoms by accumulating celiac particles in the circulation.
Screening
Significant elevation of triacylglycerols may result in a milky plasma, and refraction of light by celiac particles produces a milky consistency that accumulates in the plasma as a layer of milky oil when left at 4 degrees C for 24 hours, which has diagnostic value when covered with clarified plasma. Lipoprotein lipase activity is not restored after injection of type IV heparin (postheparin lipolysis). If the plasma under the emulsion is cloudy, VLDL and triacylglycerols are also elevated (type V hyperlipoproteinemia).
Diagnosis
Hyperlipoproteinemia type I can be diagnosed by combining clinical manifestations, lipid tests, ultrasound and local tissue biopsy. Diagnostic points are the following two points.
1. Symptoms such as abdominal pain, yellow tumor, retinal version, hepatosplenomegaly, etc.
2. plasma is milky, celiac particles refract light to produce milky, placed in the environment of 4 ℃, after 24 hours in the plasma there is a layer of milky oil accumulation.
Treatment
For abdominal colic, the first step is fasting, sedation with isotonic saline or 5% dextrose solution, or symptomatic application of sedative or analgesic drugs. Long-term diets should limit fat intake to a maximum of 15-30 g/day, and fats should be rich in branched-chain triacylglycerols.