48.Diseases of the Muscle

Question 1

This is the third major form of inflammatory myopathy, and is the most common inflammatorh myopathy in patients older than 50 years

Answer 1

Inclusion Body Myositis (p1423)

Question 2

Immunopathologic characteristic of DM

Answer 2

immune complexes, IgG, IgM, complement (C3), and membrane atrack complexes are depisited in the walls of cenules and arterioles. DM is predominantly humoral (p1422)

Question 3

Immunopathologic change in PM

Answer 3

In PM, there are a large number of activated T cells, mainly CD8 class.

Question 4

Defining feature of Inclusion body myositis. (IBM)

Answer 4

Intracytoplasmic and intranuclear inclusions. (p1423)

Question 5

Characterized by a steadily progressive, painless muscular weakness and modest atrophy, which is usually distal in the arms and both proximal and distal in the legs.

Answer 5

Inclusion Body Myositis

Question 6

Pattern of involvement in IBM

Answer 6

Selective weakness of the flexor pollicis longus, isolated quadriceps weakness or neck extensor weakness. Deltoids are spared and thumb flexors are weak.

Question 7

cytosolic antibodies in IBM

Answer 7

anti-cN1; NT5C1A (p1424)

Question 8

ESR of polymyalgia rheumatica

Answer 8

above 65mm/h

Question 9

Features that virtually exclude a myositis

Answer 9

1. Lack of reduced peak power of contraction

2. normal EMG, serum enzymes and muscle biopsy

Question 10

Mistakable for PM.
Scleroderma-like appearance of the skin and flexion contractures at the kneew and elbows associated w/ hyperglobulinemia, elevated sedimentation rate and eosinophilia.
Associated with heavy exercise.

Answer 10

Eosinophilic Fascitis (p1425)

Question 11

Painful swelling of a calf muscle.
When connective tissue and muscle are both damaged, a chaotic regeneration of fibroblasts and myoblasts may result, forming a pseudotumorous mass that may persist indefinitely.

Answer 11

Eosinophilic monomyositis

Question 12

Subacute polymyositis.
The features of the muscle disorder were typical of PM except that the inflammatory infiltration was predominantly eosinophilic and the muscles were swollen and painful.

Answer 12

Eosinophilic Polymyositis (p.1425)

Question 13

8 Systemic Manifestations of Eosinophilic Polymyositis

Answer 13

1. )Eosinophilia (20-55%of WBC)
2. )Cardiac involvement (conduction disturbances and congestion failure)
3. ) Vascular disorder (Raynaud phenomenon, subungual hemorrhages)
4. )Pulmonary infiltrates
5. )Stroke
6. )Anemia
7. )Neuropathy
8. )Hypergammaglobulinemia

Question 14

Mutation of what gene associated with with Eosinophilic monomyositis and polymyositis?

Answer 14

CAPN3

gene for calpain 3

Question 15

Severe generalized myalgia and eosinophilia of the peripheral blood following ingestion of contaminated Al-tryptophan

Answer 15

Eosinophilia-Myalgia syndrome.

Question 16

Inflammatory process localized to the extraocular muscles

Answer 16

aacute Orbital myositis

Question 17

X-linked recessive
Dystrophin gene
Affects proximal then distal muscles
cardiac muscle

Answer 17

Duchenne/Becker

Question 18

X-linked
Emerin
Proximal muscles, joint contractures, cardiac arrhythmias

Answer 18

Emery-Dreifuss

Question 19

X linked recessive

FHL1

Answer 19

Scapuloperoneal

Question 20

Most frequent and best known of the early onset mudcular dystrophies.

Answer 20

Duchenne Muscular Dystrophy

Question 21

Enzyme defective in type II glycogenosis or Pompe

Answer 21

Acid Maltase

Question 22

Type III glycogenosis

Answer 22

Cori-Forbes

Question 23

Enzyme def in cori-Forbes

Answer 23

debrancher