10/26 Lipid Transport Disorders

Question 1

monogenic dyslipidemias

Answer 1

single gene mutation
5-10% of cases
mendelian inheritance
lifestyle changes have little effect, needs drugs

Question 2

polygenic dyslipidemias

Answer 2

multiple genes contribute
90-95% of cases
interaction with enviornment
most respond well to lifestyle changes

Question 3

hyperchylomicronemia (AR)

Answer 3

Patho: LPL or ApoCII deficiency

Labs: elevated chylomicrons/cholesterol/TG

Clinical: pancreatitis, hepatosplenomegaly, eruptive xanthomas, supernatant is creamy

Atherosclerosis: no increased risk

Question 4

familial hypercholesterolemia (AD)

Answer 4

Patho: absent/defective LDL receptors, or defective ApoB-100

Labs: elevated LDL/super high cholesterol (sometimes elevated VLDL)

Clinical: achilles xanthomas, thickened Achilles tendons, corneal arcus

Atherosclerosis: accelerated, may have MI before 20

Drugs: 1st statins, 2nd ezetimibe

Question 5

dysbetalipoproteinemia (AR)

Answer 5

Patho: defective ApoE

Labs: elevated chylomicrons/VLDL

Clinical: tuberoeruptive xanthomas, palmar xanthomas

Atherosclerosis: premature

Question 6

hypertriglyceridemia (AD)

Answer 6

Patho: overproduction of VLDL

Labs: elevated TGs/VLDL

Clinical: acute pancreatitis, related to insulin resistance

Question 7

Abetalipoproteinemia (AR)

Answer 7

Patho: mutation in MTP large subunit

Labs: vv low plasma TG/cholesterol

Clinical: acanthocytes, retinitis pigmentosa, neuroligical degeneration, hepatomegaly, ataxia

Treatment: large supplements of fat-soluable vitamins and essential fatty acids, decrease fat intake

Question 8

Metabolic Syndrome

Answer 8

polygenic

Patho: shitty lifestyle

Clinical: HTN, obesity, hyperinsulinemia, diabetes, hypertriglyceridemia, small/dense LDL, low HDL, hypercoagulability inflammation

Atherosclerosis: very high risk

Notes: related to insulin resistance, acanthosis nigricans in children (linear pigmentation on the back of the neck)

Treatment: lifestyle, pharmacological tx of devil’s triad

Question 9

calculation of [LDL] in plasma

Answer 9

friedewald formula

LDL = total cholesterol - HDL - (TG/5)

only works if TGs are less than 400 mg/dL

Question 10

ideal total cholesterol concentration

Answer 10

under 200 mg/dL

Question 11

ideal triglyceride concentration

Answer 11

under 200 mg/dL

Question 12

ideal LDL concentration

Answer 12

under 100 mg/dL

Question 13

ideal HDL concentration

Answer 13

35-50 mg/dL