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Biochemistry-Principles and Diseases Flashcards

1
Q

Adenosine Deaminase Deficiency- Description

A

Excess ATP and dATP imbalances nucleotide pool via feedback inhibition of Ribonucleotide Reductase. Prevents DNA synthesis and thus decreases lymphocyte count.

One of the major causes of autosomal recessive SCID.

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2
Q

Lesch-Nyhan Syndrome - Description, findings, treatments

A

Defective purine salvage due to absent HGPRT enzyme which converts hypoxanthine to IMP and guanine to GMP. Results in excess uric acid and de novo purine synthesis. X-linked recessive

Findings: intellectual disability, self-mutilation, aggression, hyperuricemia, gout, dystonia

Treatment: Allopurinol or Febuxostat

*HGPRT = Hyperuricemia, Gout, Pissed-Off, Retardation, dsyTonia

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3
Q

DNA Repair Mechanisms - Nucleotide Excision Repair

A

Single Strand. Repairs large, bulky, helix-distorting lesions. Occurs in G1 phase. Defective in Xeroderma Pigmentosum.

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4
Q

DNA Repair Mechanisms- Base Excision Repair

A

Single Strand. Base-specific glycosylases removes altered bases and creates AP site which are excised by AP endonuclease and lyase. DNA Poly fills in the gap. Active throughout the cell cycle. Important for repair of toxic/sponatneous deamination.

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5
Q

DNA Repair Mechanisms- Mismatch Repair

A

Single Strand. Newly synthesized strand is recognized (How?) and mismatched nucleotides are removed. Occurs predominantly in G2 phase. Defective in HNPCC.

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6
Q

DNA Repair Mechanisms- Nonhomologous End Joining

A

Double Strand. Brings together 2 ends of DNA fragments to repair double-stranded breaks. No requirement for homology. Some DNA may be lost. Deficient in Ataxia Telangiectasia and Franconi Anemia.

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7
Q

RNA Polymerases- Names and products

A

RNA Poly 1 makes rRNA- ‘r = rampant, most numerous’
RNA Poly II makes mRNA- ‘m = massive, largest’
RNA Poly III makes tRNA- ‘t= tiny, smallest’

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8
Q

Where does N-linked glycosylation take place within the cell?

A

Rough Endoplasmic Reticulum. This structure forms Nissl Bodies in neurons .

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9
Q

Where does O-linked glycosylation take place within the cell?

A

Golgi. Also site where mannose-6-p is added to proteins to traffic to lysosomes.

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10
Q

I-Cell Disease - Description and findings

A

Inclusion cell disease. Inherited lysosomal storage disease, in which the golgi fails to phosphorylate manose residues. Results in decreased mannose-6-p on glycoproteins, which are then secreted extracellularly.

Findings: Coarse facies, clouded corneas, restricted joint movement, high plasma levels of lysosomal protiens. Often fatal in childhood.

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11
Q

Vesicular trafficking proteins- 3 types and their function

A

COPI - Retrograde: Golgi–> cisGolgi–> ER
COPII - Anteriograde: ER–> cisGolgi
Clatherin- Variable: transGolgi–> Lysosomes / PM–>endosomes

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12
Q

Name 6 drugs that act on microtubules

A 
Mebendazole - antihelmenthic
Griseofulvin - antifungal
Cochicine - antigout
Vincristine/Vinblastine - anticancer
Paclitaxel -anticancer

Microtubules Get Constricted Very Poorly

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13
Q

Kartagener Syndrome / Primary Ciliary Dyskenesia- Description and signs

A

Immotile cilia die to a dynein arm defect. Results in male and female infertility. Increased risk of ectopic pregnancy.

Findings: bronchiectasis, recurrent sinusitis, situs inversus (dextrocardia), the latter is not found in CF.

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14
Q

Collagen- Mnemonic

A

Be (So Totally) Cool Read Books

Collagen Type I: Bone, Skin, Tendon
Collagen Type II: Cartilage
Collagen Type III: Reticulin (found in blood vessels)
Collagen Type IV: Basement membrane

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15
Q

Type I Collagen- Description and pathology

A

Most common, found in Bone, Skin and Tendon, Involved in LATE wound repair.

Osteogenesis Imperfecta type I results from Collagen I deficiency.

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16
Q

Type II Collagen- Description

A

Found in cartilage, vitreous body nucleus pulposus.

Think CarTWOlage = Type II Collagen

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17
Q

Type III Collagen- Description and pathology

A

Reticulin- Blood Vessels and Granulation Tissues (early wound healing). skin, uterus, fetal tissue,

Deficient in Ehlers-Danlos Syndrome (vascular type, uncommon).

Think Type ‘ThreE D’

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18
Q

Type IV Collagen- Description and pathology

A

Basement membrane , basal lamina, lens.

Think Type IV ‘under the floor’

Defective in Alport Syndrome, targeted by autoantibodies in Goodpasture Syndrome.

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19
Q

Osteogenesis Imperfecta-Description and findings

A

Common form is autosomal dominant with decreased production of otherwise normal Type I collagen,

Findings: multiple fractures with minimal trauma, blue sclerae, hearing loss (abnormal ossicles), dental imperfections d/t lack of dentin.

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20
Q

Ehlers-Danlos Syndrome- Description and findings

A

Faulty collagen synthesis. Multiple subtypes. Hypermobility Subtype is most common. Classical Subtype is due to mutation in Type V Collagen. Uncommon Vascular Subtype is due to deficient Type III Collagen.

Findings: Hyperextensible skin, hypermobile joints, and bleeding tendency. May also be associated with joint dislocations, berry aneurysms, aortic aneurysms, and organ rupture.

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21
Q

Menkes Disease- Description and findings

A

X-linked recessive connective tissue disease caused by impaired copper absorption and transport due to defective Menkes protein (ATP74) “kink” hair growth, growth retardation and hypotonia.

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22
Q

McCune-Albright Syndrome- Description and findings

A

Due to mutation effecting G-protein signaling. Lethal if mutation occurs before fertilization but survivable in patients with mosaicism.

Findings: unilateral café-au-lait spots, polyostotic fibrous dysplasia, precocious puberty, multiple endocrine abnormalities.

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23
Q

When should you consider the occurrence of ‘Uniparental Disomy’ in evaluation of a patient?

A

When a patient manifests symptoms of a recessive disorder when only one biological parent is a carrier.

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24
Q

Prader-Willi Syndrome- Description and findings

A

Maternal imprinting: Maternal gene is silent, Paternal gene is deleted/mutated. (25% of cases are due to maternal uniparental disomy)

Findings: hyperphagia, obesity, intellectual disability, hypogonadism, and hypertonia.

Think: “Prader-willi = deletion of Paternal gene”

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25
Q

Angelman Syndrome- Description and findings

A

Paternal imprinting: Paternal gene is silent and Maternal gene is mutated/deleted. (5% of cases due to paternal uniparental disomy)

Findings: Inappropriate laughter, seizures, ataxia and severe intellectual disability. “Happy Puppet”

Think: “angelMan’s = deletion of Maternal gene”

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26
Q

Duchenne Muscular Dystrophy- Description and findings

A

X-linked disorder due to frameshift mutation in the dystrophin gene. Impairs muscle regeneration.

Findings: Weakness beginning in pelvic girdle and progressing superiorly. Psuedohypertophy of calf muscles due to fibrofatty replacement of muscle. Pts may show ‘Gower maneuver.’ Onset before 5 yrs of age. Death due to dilated cardiomyopathy common. Labs show elevated CPK and aldolase. Confirm with muscle biopsy.

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27
Q

Cystic Fibrosis- Description, findings and treatments

A

Autosomal recessive defects in the CFTR gene on Ch 7. Common is deltaF508. Defects cause increased intracellular Cl- which in turn causes increased absorption of Na+ to counter. This causes H20 resorption and abnormally thick mucus plugs in the airways and GI tract. Increased Cl- in sweat test is diagnostic. (CFTR reabsorbs Cl- in sweat glands)

Findings: Recurrent pulmonary infections, chronic bronchitis and bronchiectasis in upper airways(!), pancreatic insufficiency, malabsorption with steatorrhea, and nasal polyps. Infertility in males, subfertility in females, and fat-soluble vitamin insufficiency. Meconium ileus in newborns(!)

Treatment: N-acetylcystein to loosen mucus plugs, DNAse to clear leukocytic debris.

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28
Q

Becker Muscular Dystrophy- Description

A

X-linked disorder similar to DMD but less severe. Due to non-frameshift insertions into dystrophin gene, leaving it partially functional. Presents in adolescence or early adulthood.

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29
Q

Myotonic Dystrophy Type I- Description and findings

A

Autosomal dominant disorder caused by CTG trinucleotide repeat expansion in the DMPK gene which leads to abnormal expression of myotonin protein kinase.

Findings: Myotonia, muscle wasting, cataracts, testicular atrophy, frontal balding, arrhythmia.

Think: “My Tonia, My Testicles, My Ticker, My Toupee”

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30
Q

Fragile X Syndrome- Description and findings

A

X-linked defect affecting the methylation and expression of the FMR1 gene. The 2nd most common cause of mental retardation after Down syndrome. Trinucleotide repeat disorder. (CGG)

Findings: post pubertal macroochidism, long face with a large jaw, large everted ears, autism, mitral valve prolaps.

Think: “fragile X = eXtra large testes, jaw, ears”

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31
Q

Name the four Trinucleotide Repeat diseases and the repeat sequence unique to each.

A

Fragile X syndrome = (CGG)
Friedriech ataxia = (GAA)
Huntington Disease = (CAG)
Myotonic Distrophy = (CTG)

Think: X-Girlfriend’s First Aid Helped Ace My Test

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32
Q

Down Syndrome- Description and findings including 1st and 2nd trimester screens

A

Trisomy 21 (1:700)Most common cause of intellectual disability. 95% of cases due to maternal nondisjunction. Associated with advanced maternal age (>45 = 1:25)

Findings: Intellectual disability, flat facies, single palmer crease, duodenal atresia, Hirschprung disease, congenital heart defect (ASD), increased risk of ALL and AML. Increased risk of Alzheimer disease (21 codes for amyloid protein)

1st Trimester: PAPP-A is down, free beta-hCG is up.
Increased nuchal translucency and hypoplastic nasal bone

2nd Trimester: alpha-fetoprotein is down, beta-hCG is up, estriol is down, inhibin A is up

33
Q

Edwards Syndrome- Description and findings including 1st trimester and quad screen

A 
Trisomy 18 (1:8000) Think: "E(dwards)lection age = 18"
Second most common trisomy resulting in live birth.

Findings: Severe intellectual disability rocker-bottom feat, micrognathia, low set ears, clenched hands with overlapping fingers, prominent occiput, congential heart disease. Death usually occurs before 1 year.

Tri-screen: PAPP-A and beta-hGC are both down
Quad-screen: alpha-fetoprotein, beta-hGC, estriol and inhibin A are all down

34
Q

Patau Syndrome- Description and findings including first trimester screen

A

Trisomy 13 (1:15,000) Think: “P(atau)uberty age = 13”

Findings: Severe intellectual disability, rocker-bottom feet, microphthalmia, microcephaly, cleft liP/Pallet, holoProsencephaly, Polydactyly, congenital heart disease, cutis aplasia. Death within 1 year.

Tri-screen: PAPP-A and beta-hGC are both down, increased nuchal translucency

35
Q

Cri-du-chat Syndrome- Description and findings

A

Congenital microdeletion of short arm of Ch 5. (46XX or XY, 5p-)

Findings: Microcephaly, moderate to severe intellectual disability, mewing cry, epicanthal folds, cardiac abnormalities (VSD)

36
Q

Williams Syndrome-Description and findings

A

Congential microdeletion of long arm of Ch7. Section includes the Elastin gene.

Findings: Distinctive ‘Elfin’ faces, intellectual disability, hypercalcemia, (increased sensitivity to Vitamin D), well-developed verbal skills, extreme friendliness with strangers, cardiovascular problems.

37
Q

22q11 Deletion Syndromes- Name two, describe their characteristic findings

A

Microdeletion at 22q11. Variable presentation.
Findings: Cleft lip and palet, Abnormal facies, Thymic aplasia, Cardiac defects, Hypocalcemia secondary to parathyroid aplasia, (CATCH-22)

DiGeorge Syndrome- thymic, parathyroid and cardiac defects
Velocardiofacial Syndrome- palate, facial and cardiac defects

38
Q

Vitamin A- name, function, deficiency, excess

A

Retinol
Antioxidant, constituent of visual pigment, necessary for cellular differentiation. ATRA used to treat PML.

Deficiency: night blindness (nyctalopia), dry scaly skin (xerosis cutis), corneal degeneration (keratomalacia), bitot spots conjunctiva, immunosupression

Excess: acute toxicity- nausea, vamiting, vertigo and blurred vision.
chronic toxicity- alopecia, dry skin, hepatic toxicity and enlargement, arthralgias and pseudotumor cerebri. Is teratogentic.

39
Q

Vitamin B1-name, function, deficiency and 3 diseases

A

Thiamine. An essential cofactor for several dehydrogenase enzymes as TPP.
Pyruvate Dehydrogenase (glycolysis to TCA)
alpha-ketoglutarate dehydrogenase (TCA)
Transketolase (HMP shunt)
Branched-chaine ketoacid dehydrogenase

Think “ATP: alpha-ketoglutarate dehydrogenase, Transketolase, Pyruvate Dehydrogenase”

Deficiency: Impaired glucose breakdown–>ATP depletion, worsened by glucose infusion. High met tissues affected first. Malnutrition and alcoholism. NEVER give an alcoholic a bag of glucose without giving a slug of thiamine.

Wernicke-Korsakoff: confusion, ophthalmoplegia, ataxia, confabulation, personality change, permanent memory loss. Damage to medial dorsal nucleaus of the thalamus, mammillary bodies

Dry Beriberi: Polyneuritis, symmetrical muscle wasting

Wet Beriberi: high-output cardiac failure, edema

40
Q

Vitamin B2- name, function, deficiency

A

riboflavin
component of flavins FAD and FMN, used as cofactors in REDOX reactions. (B2= 2 ATP)

Deficiency: Cheilosis (inflammation of lips, scaling and fissures at the corners of the mouth), Corneal vascularization. “The 2 C’s of B2”

41
Q

Vitamin B3- name, function, deficiency, excess

A

niacin
constituent of NAD, NADP. used in REDOX reactions. Derivative of Tyrptophan. Synthesis requires vitamins B2 and B6. Used to to treat dislipidemia, lowers levels of VLDL and raises levels of HDL.

Deficiency: Glossitis. Severe deficiency leads to pellagra: Diarrhea, Dementia, Dermatitis (C3/C4 dermatome rash ‘collar’, hyperpigmentation of sun-exposed skin)

Excess: Facial flushing, (can be avoided by taking aspirin) hyperglycemia, hyperuricemia

42
Q

Vitamin B5- name, function, deficiency

A

Pantothenic acid “B5 is the PENTO-thenic acid”
Essential component of coenzyme A and fatty acid synthase.

Deficiency: Dermatitis (starts as burning on soles of feet) enteritis, alopecia, adrenal insuficiency

43
Q

Vitamin B6- name, function, deficiency

A

Pyridoxine
Converted to PLP, a cofactor for AST/ALT, glycogen phosphorylase. Synthesis of cystathionine, heme, niacin, histamine, and neurotransmitters including serotonin, epinephrine, norepinephrine, dopamine and GABA

Deficiency: Convulsions, hyperirritability, peripheral neuropathy, sideroblasitic anemias due to impaired heme synthesis and iron excess.

Isoniazid and oral contraceptives can induce deficiency

44
Q

Vitamin B7- name, function, deficiency

A

Biotin
Cofactor for carboxylation enzymes.

Deficiency is rare. Dermatitis, alopecia, enteritis. Caused by antibiotic use or excessive ingestion of raw egg whites. (Avidin in egg whites)

45
Q

Vitamin B9- name, function, deficiency

A

Folate
Converted to THF, coenzyme for 1-carbon transfer/methylation reactions. Important for synthesis of nitrogenous bases in DNA and RNA. Absorbed in jejunum. Found in foliage.

Deficiency: Most common deficiency in US. Macrocytic, megaloblastic anemia, hypersegmented PMNs, glossitis, NO NEUROLOGICAL SYMPTOMS. Increased homocysteine, normal methylmalonic acid. Seen alcoholism and pregnancy. Supplement early in pregnancy.

46
Q

Vitamin B12- name, function, deficiency

A

Cofactor for homocysteine methyltransferase and methylmalonyl-CoA mutase. Reserve pool (several years) stored in liver.

Deficiency: Due to absence of terminal ileum, dietary insufficiency, lack of Intrinsic Factor. Signs of macrocytic, megaloblastic anemia, hypersegmented PMNs, parasthesias, and degradation of DCML, CST, SCT d/t abnormal myelin. Associated with increased serum levels of homocysteine and methylmalonic acid, compare to B9 deficiency. Can cause permanent damage if prolonged.

47
Q

Vitamin C- name, function, deficiency, excess

A

ascorbic acid
Antioxidant. Necessary for iron absorption by reducing it to Fe2+ state. Necessary for hydroxylation of proline and lysine in collagen synthesis. Necessary for Dopamine beta-Hydroxylase, which converts dopamine to NE. Ancillary treatment for methemoglobinemia.

Deficiency: Scurvy. swollen gums, bruising, petechia, hemarthrosis, anemia, poor wound healing, perifollicular and subperiostial hemorrhages, ‘corkscrew hair.’ Weakened immune responses.

Excess: N/V, fever, diarrhea, fatigue, calcium, oxalate nephrolithiasis, can increase risk of iron toxicity in predisposed individuals (transfusion patients, heriditary hemochromatosis)

48
Q

Vitamin D- names, function, deficiency, excess

A

D2=ergocalciferol, from plants
D3=cholecalciferol, from milk and sun-exposed skin
25-OH D3= storage form
1,25-(OH)2D3=calcitriol= active form

Increases intestinal absorption of calcium and phosphate, increases bone mineralization. Oral vitamin D is absorbed in the jejunum.

Deficiency: Rickets in children, osteomalacia in adults, hypocalcemic tetany. Breastfed infants should receive oral vitamin D. Deficiency is exacerbated by low sun exposure, pigmented skin, prematurity. Other causes of low D include, liver failure, renal failure, alcohol use

Excess: Hypercalcemia, hypercalciuria, loss of appetite, stupor. Seen in granulomatous diseases due to Mac secretion of alpha-hydroxylases.

49
Q

Vitamin E- name, function, deficiency, excess

A

Tocopherol, tocotrienol
Antioxidant (protects RBCs and membranes). CAN ENHANCE THE ANTICOAGULANT EFFECTS OF WARFARIN

Deficiency: Hemolytic anemia, acanthyocytosis, muscle weakeness, posterior column and spinocerebellar tract demyelination. Neurologic presentation may appear similar to B12 deficiency, but without megoblastic anemia or increases serum methylmalonic acid levels.

Excess: leads to coagulopathy d/t prevention of synthesis of clotting factors.

50
Q

Vitamin K- name, function, deficiency

A

phytomenadione, phylloquinone, phytonadione
Cofactor for the gamma-carboxylation of glutamic acid residues on various proteins required for blood clotting. Factors II, VII, IX, X and protein C & S. WARFARIN is Vit K antagonist

Deficiency: Neonatal hemorrhage with increased PT and PTT but normal bleeding time. Can occur after prolonged use of antibiotics. Give newborns vit K shot.

51
Q

Zinc- function, deficiency

A

Mineral essential for the activity of 100+ enzymes and zinc fingers.

Deficiency: Delayed wound healing, hypogonadism, decreased adult hair, dysguesia, anosmia, acrodermatitis enteropathica. May predispose to alcoholic cirrhosis.

52
Q

Kwashiorkor Syndrome- description

A

Protein malnutrition resulting in skin lesions, edema d/t decreased plasma oncotic pressure, liver malfunction (fatty change d/t decreased apoliprotein synthesis). Clinical presentation is small child with swollen belly.

MEAL: Malnutrition, Edema, Anemia, Liver (fatty)

53
Q

Marasmus Syndrome- description

A

Total caloric malnutrition resulting in muscle wasting, loss of subcutaneous fat and variable edema.

Marasmus = Muscle wasting

54
Q

Pyruvate Dehydrogenase Deficiency- description, findings, treatment

A

Causes a buildup of pyruvate that gets shunted into lactate (via LDH) and alanine (via ALT)

Findings: Neurologic defects, lactic acidosis, increased serum alanine in infancy

Treatment: increase intake of ketogenic nutrients (high fat content or increased lysine and leucine)

Lysine and Leucine- the onLy pureLy ketogenic aa.

55
Q

G6PDH Deficiency- description and findings

A

X-linked recessive disorder, most common human enzyme deficiency. More common in blacks. Decreased NADPH in RBCs leads to hemolytic anemia due to oxidative membrane damage.
Can be caused by fava beans, sulfonamides, primaquine, anti-Tb drugs, and inflammation.

Findings: Heinz bodies and Bite cells on blood smear.

56
Q

Essential Fructosuria- description and findings

A

Defect in fructokinase. Autosomal recessive. Benign, asymptomatic condition, since fructose is not trapped in cells.

Findings: fructose appears in blood and urine

57
Q

Fructose Intolerance- description, findings and treatment

A

Autosomal recessive defect in Aldolase B. Fructose-1-P accumulates in cells, causing decrease in available P which stops glycogenolysis and gluconeogenesis.

Findings: Urine (-) for fructose but (+) for reducing sugars. hypoglycemia, jaundice, cirrhosis, vomiting

Tx: decrease intake of both fructose and sucrose

58
Q

Galactokinase Deficiency- description and findings

A

Autosomal recessive deficiency of galactokinase. Galactitol accumulates if galactose is present in diet.

Findings: galactose appears in blood and urine, infantile cataracts, may present as failure to track objects or develop a social smile.

59
Q

Classic galactosemia- description and findings

A

Autosomal recessive abscence of galactose-1-P Uridyltransferase. Accumulation of toxic substances.

Findings: Failure to thrive, jaundice, hepatomegaly, infantile cataracts, intellectual disability. Can lead to E. coli sepsis in neonates.

60
Q

Hyperammonemia- description, findings and Tx

A

An acquired or hereditary condition that results in excess NH4+, which depletes alpha-ketoglutarate, leading to inhibition of the TCA cycle.

Findings: Tremor (asterixis), slurring of speech, somnolence, vomiting, cerebral edema, blurring of vision

Tx: limit protein in diet, Lactulose to acidify the GI tract and trap NH4+ for excretion. Rifamixin to decrease colonization of ammoniagenic bacteria, Benzoate or phenylbutyratem, which bind amino acids can be given to decrease NH4+ levels.

61
Q

N-acetylglutamate Synthase Deficiency- Description and findings

A

Required cofactor for carbamoyl phosphate synthetase I. Absence of N-acetylglutamate leads to hyperammonemia

Findings: Presents in neonates as poorly regulated respiration and body temperature, poor feeding, developmental delay, intellectual disability (identical to presentation of carbamoyl phosphate synthetase I deficiency)

62
Q

Ortnithine Transcarbamylase Deficiency- Description and findings

A

Most common urea cycle disorder. X-linked recessive! (All other urea cycle enzyme deficiencies are Autosomal Recessive). Interferes with the bodies ability to eliminate ammonia, often presents in first few days of life but may present later. Excess carbamoyl phosphate is converted to orotic acid.

Findings: Increased orotic acid in blood and urine, decreased BUN, symptoms of hyperammonemia, NO MEGALOBLASTIC ANEMIA (In contrast to orotic aciduria)

63
Q

Phenyketonuria- description, findings, Tx and complications

A

Autosomal recessive. Screening 2-3 days after birth because mother’s enxzyme covers. Due to Phe-hydroxylase deficiency or deficiency in BH4. Tyrosine becomes essential, increase in levels of Phe, ketones in urine.

Findings: intellectual disability, growth retardation, seizures, fair skin, eczema, musty body odor.

Tx: diet, BH4 supplementation

Complications: Maternal PKU- microcephaly, intellectual disability, growth retardation, congenital heart defects.

64
Q

MSUD- Description, findings and Tx

A

Autosomal recessive. Blocked degradation of BRANCHED amino acids. (Isoleucine, Leucine, Valine) due to decreased alpha-Ketoglutarate Dehydrogenase [(B1) Thiamine. Essential cofactor]. Leads to buildup of alpha-ketoacids in blood.

Findings: Urine smells like maple syrup. Causes severe CNS defects, intellectual disability and death.

Tx: Dietary restriction and B1 supplementation

Think: “ I(soleucine) L(eucine)ove V(aline)ermont MAPLE SYRUP from BRANChED maple trees.”

65
Q

Alkaptonuria- description and findings

A

Autosomal recessive, usually benign. Congenital deficiency of homogentisate oxidase in the degradative pathway of Tyr to fumarate. Pigment-forming homogentisic acid accumulates in the tissues.

Findings: Dark connective tissue, brown pigmented sclera, urine turns black on prolonged exposure to air. May have debilitating arthralgias.

66
Q

Von Gierke Disease- description, findings and Tx

A

Glycogen storage disease (Type I). Autosomal recessive deficiency in G-6-Ptase.

Findings: Severe fasting hypoglycemia, increased glycogen in the liver, increased blood lactate, increased triglycerides, increased uric acid and hepatomegaly.

Tx: frequent oral glucose and cornstarch. avoidance of fructose or galactose.

67
Q

Pompe Disease- description and findings

A

Glycogen storage disease (Type II), autosomal recessive deficiency in Lysosomal alpha-1,4-glucosidase (acid maltase)

Findings: Cardiolmegaly, hypertrophic cardiomyopathy, exercise intolerance and systemic findings lead to early death.

Think: “Pompe trashes the Pump (heart)”

68
Q

Cori Disease- description and findings

A

Glycogen storage disease (Type III). Autosomal recessive deficiency of glycogen de-branching enzyme (alpha-1,6-glucosidase). Milder form of Type 1 but gluconeogensis is intact.

69
Q

McArdle Disease- description, findings andTx

A

Glycogen storage disease (Type IV). Autosomal recessive deficiency in skeletal muscle glycogen phosphorylase (myophosphorylase).

Finding: Increased glycogen in muscle but muscle cannot break it down, leads to painful muscle cramps, myoglobinuria, with strenuous exercise and arrhythmias from electrolyte abnormalities. Blood glucose is usually not affected.

Tx: Vit B6 (cofactor)

Think: “McArdles= Muscle”

70
Q

Name 4 glycogen storage diseases.

A

Von Geirkie (Type I)- Glu-6-ptase deficiency
Pompe (Type II) - alpja-1,4-glucosidase
Cori (Type III))- alpha-1,6-glucosidase
McArdle (Type IV)- glycogen phosphorylase

Think: “Very Poor Carbohydrate Metabolism”

71
Q

Fabry Disease- description, findings,

A

Sphingolipidoses, lysosomal storage disease. X-linked recessive (!) deficiency in alpha-galactosidase A results in accumulation of ceramide trihexoside.

Findings: Peripheral neuropathy of hands/feet, angiokeratomas, cardiovascular/renal disease.

72
Q

Gaucher Disease- description, findings and Tx

A

Most common lysosomal storage disease, sphingolipidoses. Autosomal recessive deficiency in beta-glucosidase ( Glucocerebrosidase), results in accumulation of glucocerebroside.

Findings: Hepatosplenomegaly, pancytopenia, osteoporosis, aseptic necrosis of femer, bone crisis, Gaucher cells (lipid-laden osteoclasts).

Tx: recombinant glucocerebrosidase

73
Q

Neimann-Pick Disease- description and findings

A

Lysosomal storage disease, sphingolipidoses. Autosomal recessive deficiency in sphingomyelinase, resulting in an accumulation of sphingomyelin.

Findings: Progressive neurodegeneration, hepatosplenomegaly, foam cells and “cherry-red” (!) spot on macula.

Think: No(neimann) man Pick’s his nose with his sphinger.”

74
Q

Tay-Sachs Disease-description and findings

A

Lysosomal storage disease, sphingolipidoses. Autosomal recessive deficiency in hexosaminidase A, resulting in the accumulation of GM2 ganglioside and fatty acid derivatives.

Findings: Progressive neurodegeneration, developmental delay, “cherry red” spot on macula, no hepatosplenomegaly (!) as apposed to NPD.

Think: “ Tay-SaX lacks heXosamindase

75
Q

Krabbe Disease- description and findings

A

Lysosomal storage disease, sphingolipidoses. Autosomal recessive deficiency in galactocerebrosidase leading to accumulation of glactocerebroside and psychosine.

Findings: Peripheral neuropathy, developmental delay, optic atrophy, globoid cells. (looks like multinucleated giant cells)

76
Q

Metachromatic Leukodystrophy- descriptions and findings

A

Lysosomal storage disease, sphingolipidoses. Autosomal recessive deficiency in Arylsulfatase A, leading to accumulation of Cerebroside sulfate.

Findings: Central and peripheral demyelination with ataxia and dementia.

77
Q

Hurler Syndrome- description and findings

A

Lysosomal storage disease, mucopolysaccharidosis. AR deficiency in alpha-l-iduronidase leading to accumulation of heparan sulfate and dermatan sulfate.

Findings: Developmental delay, gargoylism, airway obstruction, corneal clouding, hepatosplenomegaly

78
Q

Hunter Syndrome- description and findings

A

Lysosomal storage disease, mucopolysaccharidosis. X-linked recessive (!) deficiency in iduronate sulfatase, leads to accumulation of heparan sulfate and dermatan sulfate.

Findings: Mild-hurler + aggressive behavior, no corneal clouding (!)

Think: “Hunter’s see clearly and AGGRESSIVELY aim for the X(linked recessive)!”

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