MSK: 428 - 429

Question 1

What disease is characterized by immune-mediated, widespread noncaseating granulomas?

Answer 1

Sarcoidosis

Question 2

What serum level is classically elevated in sarcoidosis?

Answer 2

ACE

Question 3

Which demographic (gender/race) is sarcoidosis most commonly found in?

Answer 3

Black females

Question 4

How do patients with sarcoidosis typically present?

Answer 4

Often asymptomatic except for enlarged lymph nodes

Question 5

Sarcoidosis is often diagnoses as an incidental finding. What can you see on CXR?

Answer 5

1. Bilateral hilar adenopathy

2. Reticular opacity

Question 6

What are 7 things sarcoidosis is associated with?

Answer 6

3 Red Things:

1. Erythema nodosum - inflammation of the fat cells under the skin usually resulting in tender red nodules on both shins
2. Lupus pernio - chronic hardened lesion on the skin that is usually red/purplish and resembles frostbite
3. Uveitis

4 Other Random Things:

1. Restrictive lung disease (interstitial fibrosis)
2. Bell palsy
3. Epithelioid granulomas containing Schaumann and asteroid bodies
4. Hypercalcemia

Question 7

What is the treatment for sarcoidosis?

Answer 7

Steroids

Question 8

Why is sarcoidosis associated with hypercalcemia?

Answer 8

Increase in 1 alpha hydroxylase mediated vitamin D activation in macrophages

Question 9

How does polymyalgia rheumatica typically present?

Answer 9

1. Pain and stiffness in shoulders and hips
2. Fever
3. Malaise
4. Weight loss

Question 10

Why is the name polymyalgia rheumatica misleading?

Answer 10

Does NOT cause muscular weakness

Question 11

What demographic is most commonly affected by polymyalgia rheumatica?

Answer 11

Women > 50 years old

Question 12

What other disease is polymyalgia rheumatica associated with?

Answer 12

Temporal (giant cell) arteritis

Question 13

What are 3 lab findings in polymyalgia rheumatica?

Answer 13

1. Increased ESR
2. Increased C-reactive protein
3. Normal CK

Question 14

Is there an effective treatment for polymyalgia rheumatica?

Answer 14

Rapid response to low-dose corticosteroids

Question 15

How does fibromyalgia present?

Answer 15

1. Chronic, widespread musculoskeletal pain
2. Stiffness
3. Paresthesias
4. Poor sleep
5. Fatigue

Question 16

What demographic is most commonly affected by fibromyalgia?

Answer 16

Females 20 - 50 years old

Question 17

What are 3 categories of treatments for fibromyalgia?

Answer 17

1. Regular exercise
2. Antidepressants (TCAs, SNRIs)
3. Anticonvulsants

Question 18

What is the signature muscular findings in polymyositis and dermatomyositis?

Answer 18

Progressive, symmetric (bilateral) proximal muscle weakness

Think: “can’t comb the hair, can’t climb the stairs”

Question 19

What distinguishes polymyositis from dermatomyositis?

Answer 19

1. Polymyositis - NO skin involvement
2. Polymyositis has endomysial inflammation vs. dermatomyositis which has perimysial inflammation (perimysial = edge of muscle fascile; think: edge is closer to the skin)
3. Polymyositis has inflammation with CD8+ cells vs. dermatomyositis which has inflammation with CD4+ cells

Question 20

What are 4 classic skin findings in dermatomyositis?

Answer 20

1. Malar rash
2. Gottron papules
3. Heliotrope rash (erythematous periorbital)
4. “Shawl and face” rash

Question 21

What are Gottron papules?

Answer 21

Scaly erythematous eruptions or red patches overlying the knuckles, elbows, and knees

Question 22

What cancer is dermatomyositis associated with?

Answer 22

Gastric

Question 23

What are 5 lab findings in polymyositis/dermatomyositis?

Answer 23

1. Increased CK
2. Positive ANA
3. Positive anti-Jo-1
4. Positive anti-SRP
5. Positive anti-Mi-2 antibodies

Question 24

What is the treatment for polymyositis/dermatomyositis?

Answer 24

Steroids

Question 25

What are two neuromuscular junction diseases?

Answer 25

1. Myasthenia gravis | 2. Lambert-Eaton myasthenic syndrome

Question 26

What is the most common neuromuscular junction disease?

Answer 26

Myasthenia gravis

Question 27

Describe the pathophysiology of myasthenia gravis.

Answer 27

Autoantibodies to the postsynaptic ACh receptor

Question 28

What do the autoantibodies in myasthenia gravis do?

Answer 28

They compete with ACh; they do NOT destroy the receptor

Question 29

How does myasthenia gravis present?

Answer 29

Ptosis, diplopia, weakness

Question 30

Compare and contrast myasthenia gravis and LEMS in terms of how the weakness changes with use.

Answer 30

Myasthenia - worsens with muscle use | LEMS - improves with muscle use

Question 31

What are 2 associations with myasthenia gravis?

Answer 31

1. Thymoma | 2. Thymic hyperplasia

Question 32

Compare and contrast the treatment of myasthenia gravis and LEMS with AChE inhibitors.

Answer 32

Myasthenia - reversal of symptoms | LEMS - minimal effect

Question 33

Describe the pathophysiology of LEMS.

Answer 33

Autoantibodies to presynaptic calcium channel leads to decreased ACh release

Question 34

How does LEMS typically present?

Answer 34

1. Proximal muscle weakness | 2. Autonomic symptoms (dry mouth, impotence)

Question 35

What is one big clinical difference between myasthenia and LEMS?

Answer 35

LEMS typically spares the eyes

Question 36

What is LEMS usually associated with?

Answer 36

Small cell lung cancer (LEMS is a paraneoplastic syndrome)

Question 37

How do we treat LEMS?

Answer 37

Resection of the cancer

Question 38

What is myositis ossificans?

Answer 38

Metaplasia of skeletal muscle to bone following muscular trauma

Question 39

Where is myositis ossificans typically observed?

Answer 39

In the extremities

Question 40

How does myositis ossificans typically present?

Answer 40

1. As a suspicious mass at site of known trauma | 2. Incidental finding on radiography