By: Maged Taman
Type I hyperlipoproteinemia:
increase in chylomicrons.
Total cholesterol is normal with high triglycerides 2000-25000
A referigerated overnight sample shows one layer of creamy chylomicrons.
Is due to to absence of LPL activity or apo- C-II. Both are autosomal recessive.
May cause eruptive xanthomata, hepatosplenomegaly, lipemia retinalis, acute pancreatitis.
Type IIa: Familial hypercholesterolemia:
increase total cholesterol and LDL with normal triglycerides and HDL.
Total cholesterol is 275-500 in the heterozygous and >500 in the hemozygus.
second to defective LDL receptor. Autosomal dominant.
Present as premature CAD, tendinous xanthomas, xanthelsma, corneal arcus.
Faimial defective Apo B100 is a similar condition with lipid profile similar to the hemozygus above.
Type IIb: Combined Hyperlipidemia:
Increase LDL and VLDL
Total cholesterol is about 250-500 with trglycerides 250-750. with high LDL and low HDL.
gentic defect causing increase apo B 100. Autosmoal dominant.
Premature CAD.
Type III: Familial dysbetalipoproteinemia:
increase VLDL and IDL, VLDL-cholestrol to triglycerides is greater than 0.3 (normal rati is 0.2)
Both total cholestroal and trigylerides are about 250-500 range. with high LDL and normal HDL. it is autosomal recessive.
Beta-VLDL detected in agarose gel electrophoresis.
Autosomal recessive second to defective or absent apo E apo-E2 instead of apo E3 that lead to less clearance of chylomicrons remanants.
Patient present with tuberoeruptive xanthoma, plamar xanthoma.
Type IV: Familial hypertriglycerdemia:
Increase triglycerides (200-500 mg/dl) and commonly low HDL . Total cholesterol and LDL are normal.
Autosmal dominant Second to heterozygous mutation of LPL gene.
Causes increase risk of premature CAD.
Type V Mixed Hypertriglycerdemia:
increase in both Chylomicrons and VLDL
A refreigerated sample overnight will show two layers creamy supernatant from chylomicorns and lower turbid from VLDL.
Mostly secondary to partial type I due to partial LPL deficiency in patient with risk for increase triglyceride as obesity, ETOH, DM, hypothyroidism, nephrotic syndrome, estorgens or tamoxifen. Primary form is possibly due to defect on apo E.
May cause hepatosplenomgaly and eruptive xanthoma as type I
