STEP2: MUSCULAR DYSTROPHIES

Question 2

What are muscular dystrophies?

Answer 2

A group of progressive diseases that affect the musculoskeletal system.

Question 3

What is the inheritance pattern of Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD)?

Answer 3

X-linked recessive.

Question 4

What types of muscular dystrophy are autosomal dominant?

Answer 4

Limb-girdle muscular dystrophy (LGMD) and facioscapulohumeral dystrophy (FSHD).

Question 5

What gene is commonly mutated in muscular dystrophies?

Answer 5

Dystrophin-protein coding gene.

Question 6

At what age does Duchenne muscular dystrophy (DMD) typically present?

Answer 6

2 to 3 years of age.

Question 7

How does Becker muscular dystrophy (BMD) differ in age of onset compared to DMD?

Answer 7

BMD usually does not become evident before the age of 15.

Question 8

What is the typical progression of DMD?

Answer 8

Rapid progression leading to ambulatory inability by age 12.

Question 9

What laboratory findings are associated with DMD and BMD?

Answer 9

Increased creatine kinase in blood tests.

Question 10

What is the primary method for diagnosing LGMD and FSHD?

Answer 10

Genetic analysis.

Question 11

What is a common treatment approach for muscular dystrophies?

Answer 11

Supportive therapy including physiotherapy and assistive devices.

Question 12

What is the life expectancy for patients with DMD?

Answer 12

Approximately 30 years.

Question 13

What is the incidence of DMD?

Answer 13

1 in 3500.

Question 14

What is the incidence of BMD?

Answer 14

1 in 30,000.

Question 15

What is a classic sign of Duchenne muscular dystrophy?

Answer 15

Gower maneuver.

Question 16

What type of mutation is typically found in the dystrophin gene causing DMD?

Answer 16

Frameshift deletion or nonsense mutation.

Question 17

What mutation typically causes Becker muscular dystrophy?

Answer 17

In-frame deletion leading to partially functional dystrophin protein.

Question 18

What is the largest known protein-coding gene in human DNA?

Answer 18

Dystrophin gene.

Question 19

What is calf pseudohypertrophy?

Answer 19

Enlargement of calf muscles despite weakness.

Question 20

What are common cardiac complications of DMD?

Answer 20

Dilated cardiomyopathy and cardiac arrhythmias.

Question 21

What is the prognosis for patients with BMD?

Answer 21

Life expectancy is 40 to 50 years.

Question 22

What is the role of glucocorticoids in the treatment of DMD?

Answer 22

They are used to slow disease progression.

Question 23

What are extramuscular manifestations of facioscapulohumeral dystrophy (FSHD)?

Answer 23

Retinal vasculopathy and hearing loss.

Question 24

What is the typical onset age for limb-girdle muscular dystrophy (LGMD)?

Answer 24

Childhood or adolescence.

Question 25

What is the confirmatory test for diagnosing DMD and BMD?

Answer 25

Genetic analysis to detect dystrophin gene mutation.

Question 26

Fill in the blank: The Gower maneuver is a classic sign of _______.

Answer 26

Duchenne muscular dystrophy.

Question 27

True or False: Only males are affected by DMD and BMD.

Answer 27

True.

Question 28

most common cause of death in patients with Becker muscular dystrophy (BMD).

Answer 28

Congestive heart failure from dilated cardiomyopathy is the most common cause of death in patients with Becker muscular dystrophy (BMD).