Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

TAS Development ✅ > Central Hypotonia ✅ > Flashcards

Central Hypotonia ✅ Flashcards

1
Q

What do you need to distinguish between when assessing hypotonia?

A
  • Central hypotonia
  • Generalised hypotonia and weakness
  • Peripheral hypotonia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Where does central hypotonia affect?

A

Predominantly head and trunk

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

Where does generalised hypotonia and weakness affect?

A

All aspects

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

Where does peripheral hypotonia affect?

A

Predominantly th elimbs

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

When does moderate to severe central hypotonia tend to be identified?

A

In the neonatal period

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

How might moderate to severe central hypotonia present in the neonatal period?

A
  • Respiratory difficulties
  • Feeding difficulties
  • ‘Floppy baby’
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What investigations may be done in an infant with central hypotonia?

A
  • Microbiological tests
  • Neuroimaging
  • Blood ammonia and lactate levels
  • Plasma and urine amino acids and urine organic acids
  • Very long chain fatty acids
  • Microarray-based comparative genomic hybridisation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

When are microbiological tests done in central hypotonia?

A

If presenting in neonatal period

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

Why are microbiological tests done in central hypotonia presenting in the neonatal period?

A

Rule out sepsis

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

What are blood ammonia and lactate levels done in central hypotonia?

A

Look for inborn errors of metabolism

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

Why are plasma and urine amino acids and urine organic acids done in central hypotonia?

A

Look for organic acidaemias

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

Why are very long chain fatty acids checked in central hypotonia?

A

Look for peroxisomal disorders

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

What specific disorder types should be considered in central hypotonia?

A
  • Aneuploidy
  • Single gene disorders
  • Metabolic disorders
  • Structural disorders
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Give an example of an aneuploidy disorder than can cause central hypotonia?

A

Down’s syndrome,

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

Give an example of a single gene disorder that can cause central hypotonia?

A

Prader-Willi syndrome

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

Give an example of a metabolic disorder that can cause central hypotonia?

A

Peroxisomal diosrders

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

Give an example of a structural disorder that can cause central hypotonia?

A

Structural brain malformations

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

What causes Down’s syndrome?

A

Additional copy of chromosome 21

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

What are the potential mechanisms behind the additional chromosome 21 in Down’s syndrome?

A
  • Non-disjunction (most common)
  • Unbalanced translocation
  • Mosaicism
20
Q

What are the clinical features of Down’s syndrome?

A
  • Typical dysmorphic features
  • Central hypotonia
  • Delay in all developmental milestones
  • Initial feeding difficulties
  • Associated congenital anomalies, including heart defects
21
Q

In what % of children with Down’s syndrome are there associated congenital anomalies?

A

50%

22
Q

What happens to the hypotonia in a child with Down’s syndrome with age?

A

In some, disappears as child develops, but many stay ‘floppy’. Studies have shown that infantile floppiness does improve over time, but often remain with some degree of hypotonia

23
Q

What is the result of continued hypotonia in a child with Down’s syndrome?

A

Responsible for much of their delay in motor milestones and impaired motor function

24
Q

Why is the belief that the floppiness of children with Down’s syndrome is responsible for their motor delay disputed?

A

Recent studies have shown that hypotonia is seen when children and adults with Down’s syndrome are not moving, and therefore it doesn’t actually impair coordinated movement

25
Q

What does the fact that in Down’s syndrome, the muscles are floppy at rest suggest?

A

There may be some peripheral component to the observed hypotonia

26
Q

What is Prader-Willi syndrome caused by?

A
  • Deletion on long arm of paternally inherited chromosome (15q13) (70%)
  • Maternal uniparental disomy (25%)
  • Imprinting defect (5%)
27
Q

Which form of Prader-Willi syndrome carries an increased risk for future pregnancies?

A

When caused by imprinting defect

28
Q

Which babeis should Prader-Willi syndrome be considered in?

A
  • Feeding difficulties
  • Needing NG tube feeding
  • Sticky saliva
  • Extreme hypokinesia
  • Combination of central hypotonia and limb dystonia
29
Q

How can children with Prader-Willi syndrome be diagnosed visually?

A

They have distinctive facial characteristics and other dysmorphic features

30
Q

What happens to feeding in children with Prader-Willi syndrome as they grow?

A

They begin to show increased appetite

31
Q

What can the increased appetite as children with Prader-Willi syndrome grow lead to?

A

Excessive eating (hyperphagia) and life-threatening obesity

32
Q

What other problems do older children with Prader-Willi syndrome have?

A
  • Hypogonadism

- Learning disabilities, can be severe

33
Q

What does hypogonadism in Prader-Willi syndrome lead to?

A

Immature development of sexual organs and delay in puberty

34
Q

In what developmental domains do children with Prader-Willi syndrome tend to be particularly impaired?

A

Emotional and social development

35
Q

What are peroxisomes?

A

Spherical organelles within cells containing important oxidative and other enzymes

36
Q

How do babies with peroxisomal disorders tend to present?

A

Extreme hypotonia of neck in context of general neonatal hypotonia

37
Q

What can peroxisomal disorders be divided into?

A
  • Global peroxisomal disorders

- Adenoleukodystrophy

38
Q

What happens in global peroxisomal disorders?

A

Few or no peroxisomes are generated, or there are single peroxisomal enzyme defects that induce a similar phenotype

39
Q

What is adenoleukodystrophy?

A

An X-linked inherited condition caused by a defect in the gene that codes for one of the ATP-binding transporters within the cell

40
Q

What blood test might detect peroxisomal disoders?

A

Measurement of very long chain fatty acids

41
Q

Is there a metabolic screen that can detect all cases of peroxisomal disorders?

A

No

42
Q

What must happen when interpreting results of metabolic tests?

A

They must be correlated with clinical findings

43
Q

What clinical features might be present with peroxisomal disorders?

A
  • Neonatal seizures
  • Retinal blindness
  • Sensorineural deafness
  • Dysmorphic features in specific syndromes
  • Hepatomegaly
  • Leukodystrophy
  • Neuronal migration defects
44
Q

What is retinal blindness also known as?

A

Leber amaurosis

45
Q

When should peroxisomal disorders be suspected in older children?

A
  • School age boy showing developmental regression with previously normal development
  • Older girls with spastic paraplegia
46
Q

What needs to be ensured when a child presents with hypotonia due to a brain malformation?

A

That the malformation is not caused by a metabolic disorder, which may require specific management

TAS Development ✅ (21 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions