Paeds neurology

Question 1

Pathophysiology Duchenne’s muscular dystrophy and beckers?

Answer 1

It is caused by a defective gene for dystrophin on the X-chromosome. Dystrophin is a protein that helps hold muscles together at the cellular level.

Becker’s muscular dystrophy is very similar to Duchennes, however the dystrophin gene is less severely affected and maintains some of its function.

Question 2

Inheritance Duchenne’s and beckers?

Answer 2

X-linked recessive

If a mother is a carrier and she has a child, that child will have a 50% chance of being a carrier if they are female and 50% chance of having the condition if they are male

Given that boys have a single X-chromosome and girls have two, girls have a spare copy of the dystrophin gene. Female carriers of the condition do not usually notice any symptoms. This makes Duchenne’s muscular dystrophy an X-linked recessive condition.

Question 3

presentation of infantile spasms/wests

Answer 3

‘salaam’ attacks: flexion of the head, trunk and arms followed by extension of the arms

Question 4

sign muscular dystrophy

Answer 4

Gower’s sign

Question 5

Investigation duchenne

Answer 5

raised creatinine kinase
genetic testing has now replaced muscle biopsy as the way to obtain a definitive diagnosis

Question 6

presentation duchenne

Answer 6

progressive proximal muscle weakness from 5 years
calf pseudohypertrophy
Gower’s sign: child uses arms to stand up from a squatted position
30% of patients have intellectual impairment

Question 7

heart defect duchenne

Answer 7

dilated cardiomyopathy