10 - 62 - DERMATOMYOSITIS

Question 1

affects 20% of patients and is a major source of morbidity and mortality in dermatomyositis

Answer 1

Interstitial lung disease (ILD)

Question 2

In adults, DM heralds the diagnosis of a coexisting internal malignancy in how many percent of patients

Answer 2

10 - 20%

Question 3

how many % of patients does not manifest clinically significant muscle weakness

Answer 3

20%

Question 4

antibidoies associated with increased risk of ILD

Answer 4

anti-MDA5 and antisynthetase autoantibodies

Question 5

antibodies associated with increased risk of having an associated cancer

Answer 5

antiTIF1-γ and anti-NXP2 autoantibodies

Question 6

The CADM umbrella can further be subclassified into exactly two groups depending on the results of further imaging (eg, magnetic resonance imaging [MRI]), electromyographic, muscle biopsy, or (now) laboratory studies of muscle enzymes.

This pertains to the subtype of CADM in which at least one of these test results is abnormal.

Answer 6

Hypomyopathic dermatomyositis

Question 6

This pertains to the subtype of CADM in which all the test results are normal.

Answer 6

Amyopathic DM

Question 7

2 peaks of DM

Answer 7

• 5 to 14 years
• 45 to 64 years of life

Question 8

Triggers of DM

Answer 8

> UVR
Strenous activity
Recent Malignancy

Question 9

In DM, there is often significant pruritus associated with the affected skin . This is usually seen on what area?

Answer 9

SCALP

which may also be described as a “tightness” or burning or with other dysesthetic qualities such as crawling or tingling. This severe pruritus on the scalp may be caused by structural damage to epidermal small-fiber nerves

Question 10

most common location affected on the scalp

Answer 10

just above and below the frontal hairline

The scalp can be affected in any location but often involves a linear band just above and below the frontal hairline.

Question 11

The skin changes in DM are often distributed to prototypical regions on the body. Enumerate these areas.

Answer 11

Question 12

Diagnostic Criteria for Dermatomyositis

Answer 12

Question 13

Cutaneous Clue to possible presence of Interstitial Lung Disease

Answer 13

Question 14

Common locations of mechanic’s hands

Answer 14

This finding was initially described as hyperkeratosis and fissuring along the medial thumb and lateral second and third digits

Question 15

Nail capillaroscopy findings in DM

Answer 15

red, edematous, often tender proximal nailfolds with ramified and dilated capillary loops with intervening pale to white avascular areas with capillary drop-out, cuticular hemorrhages, and elongated, ragged cuticles

Question 16

Cutaneous ulceration in DM warrants concern for the presence of ________

Answer 16

> antiMDA5 antibodies or malignancy (especially if necrosis is seen)
commonly occurs over gottron papules
correlated with the presence of interstitial lung disease (ILD)

Question 17

Visualization of the oral mucosa, particularly the hard palate, may provide a valuable sign to aid in the diagnosis of DM. One can observe a symmetric violaceous patch across the midline of the hard palate, termed the _______

Answer 17

Question 18

Consistent location of ovoid palatal patch

Answer 18

center of the hard palate

Question 19

antibodies associated with ovoid palatal patch

Answer 19

anti–transcriptional intermediary factor 1γ (TIF1-γ) antibodies

Question 20

pathognomonic pattern seen composed of reticulated, sometimes atrophic white macules adjacent to erythema or telangiectasias

Answer 20

“red on white”

Question 21

Calcinosis is most frequent on which areas in DM?

Answer 21

Extremities

vs systemic sclerosis where digital calcinosis is most frequent

Question 22

In both juvenile and adult DM, the presence of which antibody is associated with an increased risk of calcinosis?

Answer 22

anti–nuclear matrix protein 2 (NXP-2) antibodies

Calcinosis is also commonly seen in the anti-MDA5 subset (especially in patients with longstanding disease), 36 which is associated with known vasculopathy.

Question 23

Triad of poikiloderma

Answer 23

hyperpigmentation, hypopigmentation, and telangiectasias

Question 24

most common pulmonary manifestation in DM and is a leading cause of morbidity and mortality in these patients

Answer 24

Interstitial Lung Disease (ILD)

• affects 15 - 50% of patients

Question 25

Needed for ILD diagnosis

Answer 25

high-resolution computed tomography (CT) of the chest

Question 26

Pulmonary function test finding of DM

Answer 26

show a restrictive disease pattern with a decreased forced vital capacity (FVC) 57 or a decreased diffusion capacity of carbon monoxide.

Question 27

most common radiographic and histologic pattern in DM

Answer 27

Nonspecific interstitial pneumonia

Radiographically, basilar and peripheral ground-glass opacities and subpleural sparing characterize nonspecific interstitial pneumonia.

Question 28

The gold standard for the diagnosis of pulmonary arterial hypertension

Answer 28

Right heart catheterization

Question 29

Right heart catheterization findings of PAH

Answer 29

mean pulmonary artery pressure of 25 mm Hg or greater at rest and an end-expiratory pulmonary artery wedge pressure of 15 mm Hg or less

Question 29

Question 30

in DM, Patients often report weakness in the extensor muscles surrounding ________________

Answer 30

shoulder and pelvic girdles and proximal limbs

Question 31

Quadriceps and gluteal muscle weakness may manifest as

Answer 31

difficulty rising from a chair or toilet, climbing stairs, or stepping onto curbs.

Question 32

shoulder and upper extremity weakness may manifest as

Answer 32

difficulty washing their hair or reaching for items in overhead cupboards

Question 33

Approximately how many percent of patients complain of muscle pain with or without muscle weakness

Answer 33

30%

Question 34

risk factors for malignancy

Answer 34

increasing age, male gender, cutaneous necrosis, dysphagia, and rapid onset of myositis

Question 35

protective factors for malignancy

Answer 35

ILD, arthritis, and Raynaud phenomenon

Question 36

The major antibody associated with malignancy

Answer 36

TIF1-γ

More recent data suggest that anti-NXP2 antibodies may also be associated with cancer, although this association is not as strong

Question 37

Features of the skin examination that are particularly sensitive for dermatomyositis

Answer 37

> microscopic periungual telangiectasias
lateral digit hyperkeratosis
scalp erythema and dysesthesia

Question 38

classic c triad electromyographic findings of myositis

Answer 38

1. small amplitude, short duration, polyphasic motor unit potentials
2. fibrillations and positive sharp waves
3. complex repetitive discharges

Question 39

If a muscle biopsy is necessary to confirm the diagnosis of DM, it has the highest yield if performed within how many weeks of beginning any immunomodulatory therapy.

Answer 39

2 weeks

Question 40

ong-term survival rate for adults with DM

Answer 40

approximately 65% to 75%

Question 41

presence of this antibody is a risk factor for death

Answer 41

anti-MDA 5 antibodies