Synonym: Type 1 Hyperlipoproteinemia
Inheritance: autosomal recessive. Full expression is seen in homozygotes with reduced enzyme activity seen in heterozygotes. Both parents will be heterozygotes.
Chromosome affected: 8p22
Gene affected: LPL, with most cases representing sequence substitution and a minority involving gene deletion or duplication
Clinical features:
(1) variable history of failure to thrive as an infant
(2) onset of symptoms during childhood
(3) eruptive cutaneous xanthomas
(4) recurrent episodes of acute pancreatitis
(5) hepatosplenomegaly if on a high fat diet
(6) episodes may be triggered by an increase in triglycerides associated with uncontrolled diet, alcohol or certain drugs (oral estrogens, diuretics, beta blockers, sertraline and isotretinoin).
(7) absence or late onset of diabetes mellitus and/or steatorrhea
Laboratory findings:
(1) opaque lactescent plasma with chylomicronemia
(2) severe fasting hypertriglyceridemia (> 2,000 mg/dL if untreated)
(3) absent to markedly reduced activity of lipoprotein lipase
A patient on a low fat diet may have few findings.
