Duchenne And Spinal Muscular Atrophy (2)

Question 1

What is the most common X-linked recessive disorder?

Answer 1

Duchenne muscular dystrophy

Question 2

What does duchenne muscular dystrophy result from?

Answer 2

Missing dystrophin protein

Question 3

What does missing dystrophin protein result in?

Answer 3

Skeletal and cardiac muscle dysfunction

Leads to myofibril damage

Muscle hypoxia and fibrosis

Question 4

When is duchenne muscular dystrophy typically diagnosed?

Answer 4

By age 5

Question 5

What is used to see if a patient has duchenne muscular dystrophy?

Answer 5

ECG, elevated levels of CK in the blood, DNA analysis, and muscle biopsy

Question 6

What are the signs and symptoms of duchenne muscular dystrophy?

Answer 6

Progressive weakness

Pseudohypertrophy (enlarged calves)

Lordosis

Wide based gait/clumsiness

Gowers sign

Question 7

What happens in duchenne muscular dystrophy at age 3-5?

Answer 7

Diagnosed

Question 8

What happens in duchenne muscular dystrophy at age 6-8?

Answer 8

Stair climbing difficulties and gait deviations

Question 9

What happens in duchenne muscular dystrophy at age 8-10?

Answer 9

Decreased vital capacity and falls

Question 10

What happens in duchenne muscular dystrophy at adolescence?

Answer 10

Ability to walk is lost (average age of 12)

Question 11

What is the lifespan of duchenne muscular dystrophy?

Answer 11

Late teens to 20-30 (due to cardiac and pulmonary weakness)

Question 12

How can the lifespan in duchenne muscular dystrophy be extended?

Answer 12

Steroid treatment

Question 13

What is Becker muscular dystrophy?

Answer 13

Slowly progressive variant of duchenne muscular dystrophy

Question 14

What is spinal muscular atrophy?

Answer 14

Progressive neuromuscular disorder that destroys motor neurons at the anterior horn

Question 15

Does spinal muscular atrophy affect cognition?

Answer 15

No

Question 16

How many types of spinal muscular atrophy are there?

Answer 16

4

Question 17

What does spinal muscular atrophy prevent?

Answer 17

The body from making enough SMN protein

Question 18

What is the onset of spinal muscular atrophy type 1?

Answer 18

0-4 months

Question 19

What is the progression in spinal muscular atrophy type 1?

Answer 19

Rapidly progressive (do not achieve ability to sit unassisted)

Question 20

What is the mortality timeline in spinal muscular atrophy type 1?

Answer 20

1-10 years

Question 21

What is the onset of spinal muscular atrophy type 2?

Answer 21

6-12 months

Question 22

What is the progression in spinal muscular atrophy type 2?

Answer 22

Initially progressive, then more slowly progressive (can sit but not stand or walk)

Question 23

What is the mortality timeline in spinal muscular atrophy type 2?

Answer 23

Longevity into young adulthood

Question 24

What is the onset of spinal muscular atrophy type 3?

Answer 24

1-10 years

Question 25

What is the progression in spinal muscular atrophy type 3?

Answer 25

Slowly progressive (can stand and walk)

Question 26

What is the mortality timeline in spinal muscular atrophy type 3?

Answer 26

Near normal life expectancy

Question 27

What is the onset of spinal muscular atrophy type 4?

Answer 27

Adult onset

Question 28

What is spinal muscular atrophy type 4 often classified with?

Answer 28

Charcot-Marie-Tooth disease

Question 29

What is used for treatment in spinal muscular atrophy?

Answer 29

Disease modifying drugs, intrathecal injections, gene replacement therapy,

Question 30

What are the outcome measures for children with spinal muscular atrophy?

Answer 30

Hammersmith infant neurological examination (2-24 months) Children’s hospital of Philadelphia infant test of neuromuscular disorders (1-37 months) Hammersmith functional motor scale (> 24 months) Revised upper limb module (children and adults)