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Biochemistry Flashcards

1
Q

What is Chediak-Higashi syndrome?

A

microtubule polymerization defect (impaired phagosome-lysosome fusion) resulting in decreased phagocytosis –> recurrent pyogenic infections, partial albinism, peripheral neuropathy

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2
Q

What is Kartagener’s syndrome?

A

immotile cilia due to a dynein arm defect in cilia; results in male and female infertility (sperm immotile), bronchiectasis and recurrent sinusitis (bacteria and particles are not pushed out) and associated with situs inversus

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3
Q

Where are the cytoskeletal elements actin and myosin found?

A

microvilli, muscle contraction, cytokinesis, adherens junctions

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4
Q

Where are microtubules found?

A

cilia, flagella, mitotic spindle, neurons, centrioles

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5
Q

Where are intermediate filaments found?

A

vimentin, desmin, cytokeratin, GFAP, neurofilaments

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6
Q

What does vimentin stain?

A

connective tissue

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7
Q

What does desmin stain?

A

muscle

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8
Q

What does cytokeratin stain?

A

epithelial cells

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9
Q

What does GFAP stain?

A

neuroglia

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10
Q

What does neurofilaments stain?

A

neurons

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11
Q

type 1 collagen

A

bone, skin, tendon, dentin, fascia, cornea, late wound repair

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12
Q

type 2 collagen

A

cartilage (including hyalin), vitreous body, nucleus pulposus

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13
Q

type 3 collagen (reticulin)

A

skin, blood vessels, uterus, fetal tissue, granulation tissue

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14
Q

type 4 collagen

A

basement membrane or basal lamina

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15
Q

What are the steps for collagen synthesis and structure?

A

Inside the fibroblast

  1. translation of the collagen alpha chains (preprocollagen) in the RER
  2. hydroxylation of proline and lysine residues (requires vitamin C)
  3. glycosylation of pro-alpha-chain lysine residues and formation of procollagen in the ER
  4. exocytosis of procollagen into extracellular space

Outside fibroblast

  1. cleavage of termina, regions of procollagen –> insoluble tropocollagen
  2. cross-linkage of tropocollagen to make collagen fibrils
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16
Q

What is Ehlers-Danlos syndrome?

A

faulty collagen synthesis causing:

  1. hyperextensible skin
  2. easy bruising
  3. hypermobile joints
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17
Q

What is osteogenesis imperfecta?

A

genetic bone disorder (brittle bone disease), most common form is AD with abnormal type 1 collagen causing:

  1. multiple fractures with minimal trauma
  2. blue sclerae due to translucency of the connective tissue over the choroid
  3. hearing loss (abnormal middle ear bones)
  4. dental imperfections (lack of dentin)
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18
Q

What is Albort’s syndrome?

A

abnormal type IV collagen; most common form is X-linked recessive

Characterized by: progressive hereditary nephritis and deafness, can be associated with ocular disturbances

Note: type 4 is important for basement membrane of kidney, ears and eyes

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19
Q

What are the characteristics of Prader-Willi syndrome?

A

Results from deletion of normally active paternal allele on chromosome 15

mental retardation, hyperphagia, obesity, hypogonadism, hypotonia

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20
Q

What are the characteristics of Angelman’s syndrome?

A

Deletion of the normally active maternal allele on chromosome 15

mental retardation, seizures, ataxia, inappropriate laughter

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21
Q

What is Leber’s hereditary optic neuropathy?

A

mitochondrial myopathy through mitochondrial inheritance

degeneration of retinal ganglion cells and axons –> acute loss of central vision

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22
Q

What is achondroplasia?

A

Autosomal-dominant disease
cell signaling defect of FGF receptor 3 –> dwarfism, short limbs (but head and drunk are normal size); associated with advanced paternal age

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23
Q

What is autosomal-dominant polycystic kidney disease?

A

always bilateral!! massive enlargement of the kidneys due to multiple large cysts, associated with APKD1

presents with flank pain, hematuria, hypertension, progressive renal failure

associated with polycystic liver disease, berry aneurysms, berry aneurysms, mitral valve prolapse

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24
Q

What is familial adenomatous polyposis?

A

autosomal dominant; colon covered with adenomatous polyps –> colon cancer later on

mutation in chromosome 5 (APC gene)

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25
Q

What is familial hypercholestolemia?

A

autosomal dominant; elevated LDL due to defective LDL receptor

associated with severe atherosclerotic disease, tendon xanthomas, MI before age 20

homozygotes ~700mg/dL

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26
Q

What is hereditary hemorrhagic telangiectasia (Osler-Weber-Rendu syndrome)

A

autosomal dominant; inherited disorder of blood vessels

findings: telangiectasia, recurrent epistaxis, skin discolorations, AVMs

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27
Q

What is hereditary spherocytosis?

A

autosomal dominant; spheroid erythocytes due to spectrin or ankyrin defect; hemolytic anemia; increased MCHC

splenectomy is curative

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28
Q

What is Huntington’s disease?

A

autosomal dominant; decreased levels of GABA and ACh –> depression, progressive dementia, choreiform movements, caudate atrophy

gene located on chromosome 4; CAG repeats

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29
Q

What is Marfan’s syndrome?

A

autosomal dominant disease; fibrillin gene mutation –> connective tissue disorder affecting skeleton, heart and eyes

findings: tall with long extremities, pectus excavatum, hyperextensive joints, and long tapering fingers and toes, cystic medial necrosis of aorta –> aorta incompetence and dissecting aortic aneurysms; floppy mitral valve and subluxation of lenses

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30
Q

Neurofibromatosis type 1 (von Recklinghausen’s disease)

A

autosomal dominant disease
findings: cafe au lait spots, neural tumors, Lisch nodules, skeletal disorders (eg scoliosis) and optic pathway gliomas

on long arm of chromosome 17

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31
Q

Neurofibromatosis type 2

A

autosomal dominant disease

bilateral acoustic schwannomas, juvenile cataracts. NF2 gene on chromosome 22

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32
Q

tuberous sclerosis

A

autosomal dominant disease

findings: facial lesions, hypopigmented “ash leaf spots” on skin, cortical and retinal hamartomas, seizures, mental redardation, renal cysts and renal angiomyolipomas, cardiac rhabdomyomas, increased incidence of astrocytomas

incomplete penetrance, variable presentation

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33
Q

von Hippel-Lindau disease

A

autosomal dominant disease

findings: hemangioblastomas of retina/cerebellum/medulla; half develop mutliple biolateral renal cell carcinomas and other tumors

associated with VHL gene (tumor suppression) and chromosome 3(3p) –> constitutive expression of HIF (transcription factor) and activation of angiogenic GFs

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34
Q

What are the autosomal recessive diseases?

A

abinism, ARPKD (infantile polycystic kidney disease), cystic fibrosis, glycogen storage disease, hemochromatosis, mucopolysaccharidoses, phenylketonuria, sickle cell anemias, sphingolipidoses, thalassemia

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35
Q

cystic fibrosis

A

autosomal recessive defect in CFTR gene (chromosome 7); CFTR channel secretes Cl- in lungs and GI tract and actively absorbs Cl- from sweat

mutation causes abnormal protein folding –> degradation of channel before reaching cell surface

defective channel –> secretion of abnormally thick mucus that plugs lungs, pancreas and liver –> recurrent pulmonary infections, chronic bronchitis, bronchiectasis, pancreatic insufficiency, meconium ileus in newborns

causes infertility in males due to bilateral absence of vas deferences, fat-soluble vitamin deficiencies, failure to thrive in infancy

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36
Q

X-linked recessive disorders

A

Bruton’s agammaglobulinemia, Wiskott-Aldrich syndrome, Fabry’s disease, G6P deficiency, Ocular albinism, Lesch-Nyhan syndrome, Duchenne’s muscular dystrophy, Hunter’s Syndrome, Hemophilia A and B

“Be Wise, Fool’s GOLD Heeds Silly Hope”

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37
Q

Duchenne’s muscular dystrophy

A

X-linked frame-shift mutation –> deletion of dystrophin gene –> accelerated muscle breakdown

Weakness, pseduohypertrophy of calf muscles (due fibrofatty replacement of muscle), cardiac myopathy, use of Gowers manuever

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38
Q

Becker’s muscular dystrophy

A

X-linked mutated dystrophin gene; less severe than Duchenne’s; onset in adolescence or early adulthood

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39
Q

Fragile X syndrome

A

X-linked defect affecting methylation and expression of the FMR1 gene

findings: macro-orchidism, long face with a large jaw, large everted ears, autism, mitral valve prolapse

CGG repeats

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40
Q

Trinucleotide repeat expansion diseases

A

CAG: Huntington’s
CTG: Myotonic dystrophy
CGG: Fragile X Syndrome
GAA: Friedreich’s ataxia

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41
Q

Down’s Syndrome

A

Trisomy 21

Findings: mental retardation, flat facies, prominent epicanthal folds, simian crease, gap between 1st 2 toes, duodenal atresia, congenital heart disease, associated with increased risk of ALL and Alzheimer’s disease

pregnancy screen: decreased AFP, decreased estriol, increased B-HCG, increased inhibin A, ultrasound shows increased nuchal translucency

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42
Q

Edwards’ syndrome

A

trisomy 18

findings: severe mental retardation, rocker-bottom feet, micrognathia, low-set ears, clenched hands, promient occiput, congenital heart disease

death occurs within 1 year of birth

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43
Q

Patau’s syndrome

A

trisomy 13

findings: severe mental retardation, rocker-bottom feet, microphtalmia, microcephaly, cleft lip/palate, holoprosencephaly, polydactylyl, congenital heart disease

death usually occurs within 1 year of birth

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44
Q

Robertsonian translocation

A

nonreciprocal chromosomal translcation that most commonly involves pairs 13, 14, 15, 21, 22 –> long arms of the 2 acrocentric chromsomes fuse at the centromere and the 2 short arms are lost

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45
Q

Cri-du-chat syndrome

A

congential microdeletion of the short arm of chromosome 5 (46, XX or XY, 5p-)

findings: microcephaly, moderate to severe mental retardation, high pitched crying, epicanthal folds, cardiac abnormalities

46
Q

Williams syndrome

A

congenital microdeletion of long arm of chromosome 7

findings: distinctive “elfin” facies, mental retardation, hypercalcemia (increased sensitivity to vitamin D), well developed verbal skills, extreme friendliness to strangers, cardiovascular problems

47
Q

DiGeorge syndrome

A

deue to aberrant development of 3rd and 4th brachial pouches

thymic, parathyroid and cardiac defects

48
Q

Velocardiofacial syndrome

A

due to aberrant development of 3rd and 4th brachial pouches

palate, facial and cardiac defects

49
Q

Vitamin A (retinol)

A

fat soluble vitamin
antioxidant, used for visual pigments, normal differentiation of epithelial cells

deficiency: night blindness
excess: arthralgias, fatigue, headaches, skin changes, sore throat, alopecia, teratogenic (cleft palate, cardiac abnormalities)

50
Q

Vitamin B1 (thiamine)

A

Water soluble vitamin

Fxn: in thaimine pyrophosphate (TPP), a cofactor for 1. pyruvate dehydrogenase (glycolysis), alpha-ketoglutarate dehydrogenase (TCA), transketolase (HMP shunt), branched chain AA dehydrogenase

Deficiency: impaired glucose breakdown –> ATP depletion (brain and heart affected first), Wernicke-Korsakoff syndrome and beriberi

51
Q

Vitamin B2 (riboflavin)

A

water soluble vitamin (redox reactions)

Fxn: cofactor in redox rxns

Deficiency: cheilosis, corneal vascularization “2C’s”

52
Q

vitamin B3 (niacin)

A

water soluble vitamin

Fxn: constituent of NAD+, NADP+ (redox reactions)

Deficiency: pellagra (3D’s- diarrhea, dermatitis, dementia)

Excess: facial flushing

53
Q

Vitamin B5 (pantothenate)

A

water soluble vitamin

Fxn: essential component of CoA and fatty acid synthase

Deficiency: dermatitis, enteritis, alopecia, adrenal sufficiency

54
Q

Vitamin B6 (pyridoxine)

A

Water soluble vitamin

Fxn: converted to pyridoxal phosphate, a cofactor used in transamination, decarboxylation reactions, glycogen phosphorylase, cystathionine synthesis, and heme synthesis

deficiency: convulsions, hyperirritability, peripheral neuropathy, sideroblastic anemia

55
Q

Vitamin B12 (cobalamin)

A

water soluble vitamin

Fxn: cofactor for homocysteine methyltransferase (transfers CH3 groups to methylcobalamin) and methylmalonyl-CoA mutase

Deficiency: macrocytic, megaloblastic anemia, hypersegmented PMNs, neurologic symptoms

Note: found in animal products, synthesized by microorganisms, LARGE reserve pool in the liver

56
Q

Folic acid

A

Water soluble vitamin

Fxn: converted to THF (one carbon transfer methylation reactions) which is important for DNA and RNA synthesis

Deficiency: macrocytic, megaloblastic anemia but no neurologic symptoms

57
Q

S-adenosyl methionine

A

ATP + methionine = SAM

SAM transfers methyl units
Regeneration of methionine requires vitamin B12 and folate

58
Q

Biotin

A

Cofactor for carboxylation enzymes (which add a 1-carbon group): 1. pyruvate carboxylase, acetyl-coa carboxylase, propionyl-coa carboxylase

deficiency: rare, dematitis, alopecia, enteritis

59
Q

Vitamin C (absorbic acid)

A

Fxn: antioxidant; also 1. facilitates iron absorption 2. hydroxylation of proline and lysine in collagen synthesis 3. dopamine beta-hydroxylase which converts DA to NE

deficiency: scurvy- swollen gums, bruising, hemarthrosis, anemia, poor wound healing, WEAKENED immune response

60
Q

Vitamin D

A

fat soluble vitamin
Fxn: increase intestinal absorption of calcium and phosphate, increased bone resorption

deficiency: rickets in children, osteomalacia in adults, hypocalcemic tetany
excess: hypercalcemia, hypercalciuria, loss of appetite, stupor

61
Q

vitamin E

A

fat soluble vitamin
Fxn: antioxidant (protects erythrocytes and membranes)

deficiency:increased fragility of erythrocytes (hemolytic anemia), muscle weakness, posterior column and spinocerebellar tract demyelination

62
Q

vitamin K

A

fat soluble vitamin

fxn: catalyzes carboxylation of glutamic acid residues for blood clotting, made by intestinal flora
deficiency: neonatal hemorrhage with increased PT and PTT but normal bleeding time

necessary for clotting factors 2, 7, 9, 10, protein C and S

note: warfarin is a vitamin K antagonist

63
Q

zinc

A

fxn: impt for activity of 100+ enzymes (zinc fingers for the TF)
deficiency: delayed wound healing, hypogonadism, decreased adult hair, dysgeusia, anosmia

64
Q

Kwashiorkor

A

protein malabsorption –> skin lesions, edema, liver malfunction “small child with big belly”

MEAL: malnutrition, edema, anemia, liver (fatty)

65
Q

Marasmus

A

energy malnutrition –> tissue and muscle wasting, loss of subcutaneous fat, and variable edema

66
Q

Name examples of activated carriers.

A

Phosphoryl, electrons, acyl, CO2, 1 carbon units, CH3, aldehydes

67
Q

What are the 5 cofactors for the pyruvate dehydrogenase complex?

A
  1. pyrophosphate (B1)
  2. FAD (B2)
  3. NAD (B3)
  4. CoA (B5)
  5. lipoic acid

reaction: pyruvate + NAD + CoA –> Acetyl CoA + CO2+ NADH

68
Q

How do electron transport inhibitors work?

A

directly inhibit e transport causing decreased proton gradient and blocking of atp synthesis

ie rotenone, CN-, antimycin A, CO

69
Q

How do ATPase inhibitors work?

A

directly inhibit mitochondrial ATPase, causing increase proton gradient but no ATP is produced bc e transport stops

ie oligomycin

70
Q

How do uncoupling agents work?

A

increase permeability of membrane, causing a decreased proton gradient and increased O2 consuption; atp synthesis stops but e transport continues; PRODUCES HEAT!

ie 2,4-DNP, aspirin

71
Q

What are the irreversible enzymes involved in gluconeogenesis?

A
  1. pyruvate carboxylase (pyruvate –> oxaloacetate)
  2. PEP carboxykinase (oxaloacetate –> phosphoenolpyruvate)
  3. fructose-1,6-bisphosphatase (f-1,6-BP –> f-6-p)
  4. glucose-6-phosphatase (G6P –> glucose)

Pathway Produces Fresh Glucose

found mostly in the liver, but also found in the kidney and intestinal epithelium

72
Q

What is the purpose of the HMP shunt?

A

to provide a source of NADPH (reductive rxns), ribose for nucleotide synthesis and glycolytic intermediates

73
Q

What is chronic granulomatous disease?

A

NADPH oxidase deficiency
WBCs of pts can utilize H2O2 made by invading organisms and convert it to ROIs, but are at increased infection by catalase-positive organisms since they neutralize their own H2O2

74
Q

What is G6P dehydrogenase deficiency?

A

X-linked recessive disorder

G6P dehydrogenase is necessary to convert NADP+ to NADPH, which is needed to keep GSH reduced, which is needed to convert hydrogen peroxide to water

Without this enzyme in RBCs, they undergo hemolytic anemia due to poor RBC defense against oxidizing agents

Smear can show Heinz bodies (oxidized hg precipitated) and bite cells (phagocytic removal of the Heinz bodies by macrophages)

75
Q

essential fructosuria

A

defect in fructokinase (fructose –> f-1-p); autosomal recessive but benign, asymptomatic

symptoms: fructose in blood and urine

76
Q

fructose intolerance

A

heriditary deficiency of aldolase B (fructose-1-p –> dihydroxyacetone-P or glyceraldehyde)

results in increased f-1-p –> decreased available phosphate –> inhibition of glycogenolysis and gluconeogenesis

symptoms: hypoglycemia, jaundice, cirrhosis, vomiting
tx: decrease intake of fructose and sucrose (glucose + fructose)

77
Q

galactokinase deficiency

A

hereditary deficiency of galactokinase (galactose –> galactose-1-p)

since it cant be converted, aldose reductase converts galactose to galactitol which accumulates

symptoms: galactose in blood and urine, infantile cataracts

78
Q

classic galactosemia

A

absence of g-1-p uridyltransferase (galactose-1-p –> glucose-1-p) causing accumulation of toxic substances

symptoms: failure to thrive, jaundice, hepatomegaly, infantile cataracts, mental retardation
tx: exclude galactose and lactose from diet

79
Q

glucogenic amino acids

A

methionine, valine, arginine, histidine

80
Q

glucogenic/ketogenic amino acids

A

isoleucine, phenylalanine, threonine, tryptophan

81
Q

ketogenic amino acids

A

leucine, lysine

82
Q

acidic amino acids

A

aspartate and glutamine

83
Q

basic amino acids

A

arginine, lysine and histidine

84
Q

What is the result of hyperammonemia?

A

excess NH4+ depletes alpha-ketoglutarate –> inhibition of TCA

intoxication: tremor, slurring, somnolence, vomiting, cerebral edema, blurring of vision

85
Q

What is OTC deficiency?

A

most common urea cycle disorder that is X-linked recessive

interferes with the bodys ability to eliminate ammonia, excess carbamoyl phosphate is converted to orotic acid (pyrimidine synthesis pathway)

findings: orotic acid in blood and urine, decreased BUN, symptoms of hyperammonemia

86
Q

phenylketonuria

A

decreased phenylalanine hydroxylase (phenylalanine –> tyrosine) or THB cofactor leading to excess pheylketones in the urine

findings: mental retardation, growth retardation, seizures, fair skin, eczema, musty body odor
tx: decreased phenylalanine and increased tyrosine in diet

87
Q

aklaptonuria

A

congenital deficiency of homogentisic acid oxidase in the degradative pathway of tyrosine; autosomal recessive

findings: dark connective tissue, brown sclera, black urine, debiltating arthralgias

88
Q

albinism

A

tyrosinase deficiency (cant make melanin from tyrosine; AR) or defective tyrosine transporters (decreased amounts of tyrosine) or lack of migration of neural crest cells

89
Q

homocystinuria

A
  1. cystathionine synthase deficiency (converts homocysteine to cystathionine using B6) which the tx is decreased met and increased cys, b12, and folate
  2. decreased affinity of cystathionine synthase for B6 (tx is increased vitamin b6 in diet)
  3. homocysteine methytransferase deficiency

findings: increased homocysteine in urine, mental retardation, osteoporosis, tall stature, kyphosis, lens subluxation, and atherosclerosis

90
Q

cystinuria

A

dfect of renal tubular amino acid transporter for cysteine, ornithine, lysine and arginine in the PCT of the kidneys —> excess cysteine can cause kidney stones

91
Q

Hartnup disease

A

AR disease; defective neutral amino acid transporter on renal and intestinal epithelial cells –> tryptophan excretion in urine and decreased absorption in gut –> pellagra

92
Q

Von Gierke’s disease

A

glycogen storage disease

deficient enzyme- glucose-6-phosphatase (G6p –> glucose) causing severe fasting hypoglycemia, increased glycogen in liver, increased blood lactate and hepatomegaly

93
Q

Pompe’s disease

A

glycogen storage disease

deficient enzyme- lysosomal alpha-1,4- glucosidase causing cardiomegaly and system findings leading to early death

94
Q

Cori’s disease

A

glycogen storage disease

deficient enzyme- debranching enzyme causing milder form of Von Gierke’s disease with normal blood lactate levels

95
Q

McArdle’s disease

A

glycogen storage disease

deficient enzyme- skeletal muscle glycogen phosphorylase causing increased glycogen in muscle, but cant break it down, leading to painful muscle cramps, myoglobinuria with exercise

96
Q

Fabry’s disease

A

lysosomal storage disease (sphingolipidoses)

deficient enzyme- alpha galactosidase A (ceramide trihexoside –> glucocerebroside) causing increased ceramide trihexoside

findings: peripheral neuropathy of hands/feet, angiokeratomas, CV/renal disease

XR inheritance

97
Q

Gaucher’s disease

A

lysosomal storage disease (sphingolipidoses)

deficient enzyme- beta glucocerebrosidase (glucocerebroside –> ceremide) causing increased glucocerebroside

findings: hepatosplenomegaly, aseptic necrosis of femur, bone crises, Gaucher’s cells

AR inheritance

98
Q

Niemann-Pick disease

A

lysosomal storage disease (sphingolipidoses)

deficient enzyme- sphingomyelinase (sphingomyelin –> ceremide) causing increased sphingomyelin

findings: progressive neurodegeneration, hepatosplenomegaly, cherry red spot on the macula, foam cells

AR inheritance

“No man picks (Niemann-Pick) his nose with his sphinger (sphingomyelinase)”

99
Q

Tay-Sachs

A

lysosomal storage disease (sphingolipidoses)

deficient enzyme- hexoaminidase A (GM2 –> GM3) so GM2 ganglioside accumulates

findings: progressive neurodegeneration, developmental delay, cherry-red spot on macula, lysosomes with onion skin, NO hepatosplenomegaly

AR inheritance

“Tay-SaX lacks heXosaminidase”

100
Q

Krabbe’s disease

A

lysosomal storage disease (sphingolipidoses)

deficient enzyme- galactocerebrosidase (galactocerebroside –> ceramide) so galactocerebroside accumulates

findings: peripheral neuropathy, developmental delay, optic atrophy, globoid cells

AR inheritance

101
Q

metachromatic leukodystrophy

A

lysosomal storage disease (sphingolipidoses)

deficient enzyme- arylsulfase A (sulfatide –> galactocerebroside) so sulfatide accumulates

findings: central and peripheral demyelination with ataxia, dementia

AR inheritance

102
Q

Hurler’s syndrome

A

lysosomal storage disease (mucopolysaccharidoses)

deficient enzyme - alpha-L-iduronidase
accumulated substrate- heparan sulfatte, dermatan sulfate

findings: developmental delay, gargoylism, airway obstruction, corneal clouding, hepatosplenomegaly

AR inheritance

103
Q

Hunter’s syndrome

A

lysosomal storage disease (mucopolysaccharidoses)

deficient enzyme- iduronate sulfatase causing increased heparan sulfate, dermatan sulfate

findings: milder Hurler’s + aggressive behavior, no corneal clouding

XR inheritance

“HUNTERS see clearly (no corneal clouding) and aim for the X (X-linked recessive)

104
Q

Apo A-1

A

activates LCAT

105
Q

Apo B-100

A

binds LDL receptor, mediates VLDL secretion

106
Q

Apo C-2

A

cofactor for LDL

107
Q

Apo B-48

A

mediates chylomicron secretion

108
Q

Apo E

A

mediates extra (remnant) uptake

109
Q

Type 1 dyslipidemia (hyperchylomicronemia)

A

LPL defiency or altered Apo C-2
increased chylomicrons, elevated TG and cholesterol

pancreatitis, hepatosplenomegaly, eruptive xanthomas (no athlerosclerosis)

110
Q

Type 2A dyslipidemia (familial hypercholesterolemia)

A

AD due to absent or decreased LDL receptors –> accelerated atherlosclerosis, tendon (Achilles) xanthomas, and corneal arcus

Increased LDL, elevated cholesterol

111
Q

Type 4 dyslipidemia (hypertriglyceridemia)

A

hepatic overproduction of VLDL –> pancreatitis

increased VLDL, TG

112
Q

abetalipoproteinemia

A

hereditary (AR) inability to synthesize lipoprotiens due to deficiencies in apoB-100 and apoB-48

accumulation within enterocytes due to inability to export absorbed lipid as chylomicrons

findings: failure to thrive, steatorrhea, acanthocytosis (spur cells), ataxia, night blindness

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