Exam 2 - Metabolic disorders Flashcards

Metabolic disorders

You may prefer our related Brainscape-certified flashcards:
1
Q

over ___ different metabolic disorders identified

A

350

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Metabolic disorders are often inherited as:

A

Autosomal recessive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Newborn screening using _____ is the most commonly used population based screening method for ___________

A

blood spots

metabolic disorders

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Different catergories of metabolic disorders:

A
Carbohydrate
Amino Acid
Lipid
Urea cycle
Heavy metal transport
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Amino acid disorders

A

Phenylketonuria

Maple syrup urine disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Carbohydrate Disorder

A

Galactosemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Urea Cycle Disorder

A

Ornithine transcarbamylase deficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Heavy Metal Transport Defects

A

hemochromatosis
Cystinuria
Menkes and Wilson diseases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Lipid Disorders

A

Smith-Lemli-Opitz syndrome
MCAD, LCHAD
Zellweger syndrome
Lysosomal Storage disorders

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

PKU

A

Phenylketonuria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

PKU key clinical problems:

A

intellectual deficits, seizures, developmental delay, microcephaly, heart defects

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

PKU inheritance pattern

A

Autosomal recessive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Cause of PKU disease:

A

Lack of phenylalanine hydroxylase leads to build up of Phenylpyruvic acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

The amount of ______ and ______ eaten increases with age as the need for ____&____ increases.

A

no-protein medical foods
low-protein medical foods
energy and protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is Aspartame?

A

artificial sweetener

Aspartame is 50% phenylalanine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

High levels of phenylalanine is _____ for a normal patient, but is especially harmful for ______

A

neurotoxic

PKU patients

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Even in non-PKU patients, high levels of phenylalanine is harmful to ____ during _____

A

fetus
pregnancy
**cautious intake of this sweetener

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

MSUD

A

Maple Syrup Urine Disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

MSUD is a _______ disorder

A

Branched-chain amino acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

MSUD common among the _______ of Lancaster County, PA

A

Mennonite population

~1 in 7 is a carrier

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

MSUD key clinical symptoms

A

Poor feeding
Lethargy
Maple syrup smell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

MSUD inheritance pattern

A

Autosomal recessive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

MSUD Mutation:

A

mutation in the E1α geneone of 6 genes comprising the enzyme called branched-chain α -ketoacid dehydrogenase (BCKAD)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Cause of MSUD disease:

A

DefectiveenzymeBCKAD leads to accumulation ofBCAAs and their ketoacids, which leads to neurodegeneration and death within a few months after birth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are the branched chain amino acids:

A

valine, leucine and isoleucine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

BCAAS used as what:

A

energy sources through an oxidative pathway that uses an α -ketoacid as an intermediate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

______ of α -ketoacids is mediated by the ______ enzyme

A

Decarboxylation

branched-chain α -ketoacid dehydrogenase (BCKAD)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Treatment of MSUD

A

Dietary restriction of BCAAs. Even with treatment, episodic deterioration is common.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

New Born Screening (NBS) is available to:

A

All infants in US shortly after birth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

How is the sample collected:

A

Blood sample collected from heel prick

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

NBS screens for:

A

77 different genetic diseases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Samples are analyzed using:

A

Tandem mass spectrometry

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

2 step process:

A

1) Screening - indicates a problem MAY be present
2) Diagnostic test - confirms or dismisses whether
disease is truly present

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Many _____ screening results have _____ follow-up testing

A

Abnormal

Normal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Causes for NBS screening to indicate abnormal results:

A

Blood drawn too early

Baby is premature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Screening criteria:

A
Disease is serious
Disease undetected by exam
Incidence supports screening 
Well established confirmative testing 
Effective treatments exist 
Earlier treatment is better
Diagnosis and treatment are available 
Screening is cost effective
37
Q

MS/MS tests for:

A

Tandem Mass Spectrometry

AA, organic acid and fatty acid oxidation disorders

38
Q

Prior to MS/MS:

A

one test per genetic disorder paradigm

39
Q

MS/MS reduces __________ rate for ____

A

False positive

AA disorders

40
Q

MS/MS measures _______ simultaneously in ______

A

multiple compounds

single analysis

41
Q

FELSI

A

Financial, Ethical, Legal and Social Issues

42
Q

Financial issues:

A

increased cost of testing and who is to pay for follow-up testing (which can cost thousands of dollars)

43
Q

Ethical issues:

A

include testing for untreatable disorders and storage of testing samples

44
Q

Social issues:

A

issue of “informed consent.” Since newborn screening tests are required by law, they traditionally have not required an active informed consent process - i.e. signing document.

45
Q

Newest technology:

A

Whole Exome sequencing and whole genome sequencing

46
Q

Galactosemia key clinical problems:

A

causes intellectual disability, damage to liver, kidneys, eyes

47
Q

Galactosemia inheritance pattern:

A

Autosomal recessive

48
Q

Cause of galactosemia disorder:

A

Inability to break down galactose leads to accumulation of galactose derivatives

49
Q

Most common enzymatic abnormality in galactosemia

A

GAL-1-P uridyl transferase

50
Q

Least common enzymatic abnormalities in galactosemia

A

UDP-galactose 4-epimerase, galactokinase

51
Q

Lactose poses what issue to infants with galactosemia

A

Lactose is made up of galactose and glucose which is present in breast and cows milk

52
Q

Treatment of galactosemia:

A

Cannot eat other galactose-containing foods (e.g. garbanzo beans, milk chocolate)

Use lactose-free infant formula

53
Q

(1) hyperglycemia (diabetes mellitus), (2) Von Gierke disease, (3) fructosuria, (4) hereditary fructose intolerance, (5) Cori disease, (6) Anderson disease, (7) Tarui disease, and (8) FBPase deficiency

A

Enzymatic defects in glucose, fructose, and glycogen metabolism pathways cause these diseases

54
Q

Neonatal diabetes

A

glucokinase defect

Causes permanent neonatal diabetes

55
Q

A1C blood test:

A

estimates glucose levels in blood for previous 3 months

56
Q

Smith-lemli-opitz key clinical problems:

A

congenital anomalies of the brain, heart, genitalia, and hands

57
Q

Smith-lemli-opitz cause of disease:

A

Patients have reduced levels of cholesterol due to △7-sterol reductase defect mediating the final step in the synthesis of cholesterol

58
Q

Smith-lemli-opitz inheritance pattern:

A

Autosomal recessive

59
Q

MCAD

A

Medium-chain acyl-coenzyme A dehyrdrogenase

60
Q

MCAD key clinical problems:

A

Vomiting, lethargy, hypoglycemia (low blood sugar) – most frequent following fasting/diminished food intake

61
Q

MCAD inheritance pattern:

A

Autosomal recessive

62
Q

MCAD cause of disease:

A

Mutations in the ACADM gene, which makes MCAD. MCAD normally breaks down medium-chain fatty acids.
MCAD deficiency causes accumulation of fatty acid intermediates and failure to produce ketones to produce energy.

63
Q

MCAD is the most common:

A

Inborn error of fatty acid metabolism

64
Q

Treatment of MCAD:

A

adequate intake of calories at all times, and avoid fasting

65
Q

In MCAD patients death results unless:

A

Immediate energy source (ex: glucose) provided

66
Q

NBS for MCAD:

A

includes testing for a panel of acylcarnitines by TMS

67
Q

Most severe fatty acid oxidation disorders:

A

LCHAD

68
Q

Features of LCHAD:

A

cardiomyopathy, skeletal myopathy, retinal disease, peripheral neuropathy, sudden death

69
Q

abnormal or absence of peroxisomes (harbor enzymes that rid the cell of toxic substances in liver, kidney, brain)

A

Zellweger syndrome

70
Q

Zellweger syndrome features:

A

enlarged liver, facial deformities, intellectual disabilities, seizures

71
Q

_______ results in high levels of iron and copper build up in blood and organs

A

Zellweger syndrome

72
Q

Lysosomal storage disease:

A

Tay Sachs

73
Q

Tay Sachs clinical problems:

A

Hypotonia, spasticity, seizures, blindness

74
Q

Tay Sachs inheritance pattern:

A

Autosomal recessive

75
Q

Cause of the Tay Sachs disease:

A

Mutation in B-Hexosaminidase leads to build up of gangliosides in nerve cells in the brain, destroying brain cells

76
Q

Primary roles of Urea cycle:

A

1) prevent accumulation of nitrogenous wastes by incorporating nitrogen into urea; eventually excreted by the kidneys
2) synthesis of arginine

77
Q

Problem in the _______ can lead to accumulation of ___________ and leads to liver failure.

A

urea cycle

ammonia (a nitrogenous waste)

78
Q

OTC clinical problems:

A

progressive neurological impairment and death if untreated

79
Q

OTC inheritance pattern:

A

X-linked recessive

80
Q

Cause of OTC:

A

Ornithine transcarbamylase deficiency leads to leads to accumulation of urea precursors

81
Q

Most common urea cycle disorder:

A

OTC

82
Q

Cystinuria and cystinosis

A

abnormal cystine transport

83
Q

Hereditary Hemochromatosis

A

abnormal iron transport

84
Q

Hemochromatosis inheritance pattern

A

autosomal recessive

85
Q

Hemochromatosis clinical problems

A

fatigue, joint pain, diabetes, increased skin pigmentation, cardiomyopathy, liver enlargement, cirrhosis.

86
Q

cause of Hemochromatosis

A

Excess iron absorbed in small intestine. Accumulates in organs: liver, kidney, heart, joints, pancreas.

87
Q

Hemochromatosis gene product normally binds to ________. Normally inhibits ______ iron uptake.

A
transferrin receptor (transferrin carries iron)
transferrin mediated
88
Q

Problems with Jessie Gelsinger case (gene therapy to treat OTC):

A

May have not been informed of death in primates

Did not give truly informed consent

Jesse was not eligible to be included due to high level of ammonia

Conflict of interest may exist between researchers ability to protect financial interests

Many adverse effects in gene therapy have not been reported to the RCA

Some pt deaths may have been wrongly ascribed to underlying disease rather than trials