Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Pediatric Rheumatology Board Exam > Inflammatory Myositis 6.5% > Flashcards

Inflammatory Myositis 6.5% Flashcards

1
Q

What are the Bohan and Peter Criteria for dermatomyositis?

A

REQUIRED: Pathognomonic rash (heliotrope rash, Gottron papules)

Features:

  • proximal muscle weakness
  • elevated muscle enzymes
  • EMG changes of chronic inflammatory myositis
  • histopathological changes of inflammatory myositis

DEFINITE JDM: 3/4 features present
PROBABLE JDM: 2/4 features present

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is on the differential diagnosis for a child who develops inflammatory myositis after receiving routine vaccines?

A

Macrophagic myofasciitis: predominantly macrophagic infiltration with focal myositis in deltoids or quads at injection site of vaccine containing aluminum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the classic pattern of muscle weakness in JDM?

A

Symmetric, proximal muscle weakness
Gower sign
Trendelenburg sign - indication of weak hip abductors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

A 7 year old female presents with fatigue, difficulty climbing stairs, and violaceous hue to her eye lids. Her muscle enzymes are elevated. She answers questions in a quiet voice, and you notice that she coughs occasionally while eating her breakfast.

What muscle groups are involved that could explain her voice and cough? What additional work-up is indicated?

A

Involvement of palatopharyngeal muscles may result in difficulty swallowing and increase risk of aspiration. Dysphonia, weak/gurgling voice, nasal speech are other frequent signs.

In up to 80% of patients, subtle or even asymptomatic dysfunctional swallowing can be demonstrated by barium swallow test, which does not necessarily correlate with weakness or other measures of disease activity. Thus, all children with JDM should undergo evaluation for swallowing dysfunction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are other MSK manifestations of JDM other that muscle weakness?

A

Arthralgias
Arthritis (transient, nondeforming) may be present in 26-67% of JDM patients
Tenosynovitis or flexor nodules
Flexion contractures – knees, hips, shoulders, elbows, ankles, wrists due to myofascial inflammation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are classic skin findings in JDM?

A

Heliotrope rash
Gottron papules
Malar rash - less discrete than in lupus, spares nasolabial folds
Periungal erythema and capillaropathy
Gingival capillaropathy
Photosensitive rash - malar rash, facial erythema, shawl/V sign, linear exnesor erythema - in up to 50%
“Tear drop” erythema near inner canthi

Scalp dermatitis - up to 25%
Panniculitis
Anasarca in severe disease
Overlying SQ tissue may be edematous and indurated, including periorbital area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the implications of skin ulcers in JDM?

A

Patients with generalized rash and cutaneous ulcers may have severe and prolonged disease, but this is not observed universally.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What myositis specific antibody is seen with increased frequency in patients with JDM and generalized lipodystrophy?

A

Anti-TIF-1 (anti-p155/140)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the two most. common autoimmune rheumatologic diseases associated with lipodystrophy?

A
  1. JDM

2. JIA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are risk factors associated with the development of lipodystrophy?

A

Features of severe disease:

Calcinosis
Muscle atrophy
Joint contractures
Facial rash
Greater skin disease activity
Decreased density of periungal nailfold capillaries
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is calcinosis?

A

Dystrophic calcification that typically occurs after onset of symptomatic myositis

May occur in SQ plaques or nodules, as large deposits in muscle groups, as calcification within fascial planes, bridging joints, or as extensive SQ exoskeleton

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the risk factors for the development of calcinosis?

A 
Delay to diagnosis
Duration of untreated disease
Duration of active disease
Inadequate therapy
Underlying cardiac or pulmonary disease
Male
Older at onset
Prolonged persistent disease activity after dx
Need for steroid-sparing immunosuppression that indicates severe disease activity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are myositis-specific antibodies associated with the development of calcinosis?

A

Anti-NXP-2 (anti-MJ)
Anti-PM-Scl

Bonus: Proinflammatory cytokine polymorphisms of TNFa and IL-1a also a/w risk of development of calcinosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

For JDM, What is persistently decreased nailfold capillary density related to?

A

More severe, chronic disease course; cutaneous ulceration; development of calcinosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are complications of calcinosis

A

Cellulitis
Flexion contractures – calcinosis crosses joint margins
Severe pain – if calcinosis entraps nerves
May slowly resolve with recurrent extrusion of small flecks of calcium or development of liquid Ca salts that resorb. The latter occurs with aggressive anti-inflammatory and demineralizing treatments
Exoskeleton – SQ Ca deposition along fascial planes and within muscle. Results in severe disability

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is a potential emergency in JDM patients?

A

GI tract vasculitis

Presents as diffuse, severe, progressive abdominal pain, pancreatitis, melena, and hematemesis, which represents vasculopathy of the GI mucosa with tissue ischemia or acute mesenteric infarction

Rare, usually occurs soon after onset of sx, can occur later, poor prognosis

Can rapidly lead to death

Perforation – seen as free air on XR; multiple perforations of duodenum are difficult to see and can recur

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What myositis-specific antibodies are associated with interstitial pneumonitis in JDM?

A

Anti-Jo-1 and other antisynthetase Ab

Anti-MDA-5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are early markers of ILD in JDM?

A

KL-6 and ferritin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What type of lung involvement can be seen in moderate-severe JDM?

A

Symptomatic, restrictive lung disease

Look for decreased TLC or DLCO

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the incidence of JDM?

A

3.2 per million

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the age of onset of dermatomyositis?

A

Bimodal
Age 5-14 then
Age 45-64

Median age of onset 7 years

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the sex ratio of JDM?

A

2 female : 1 male

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

True of false: There is an increased risk of malignancy in children with JDM.

A

False

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

A 7 year old male develops calf pain and tenderness 1 week after flu-like symptoms. He has no rash. His ESR is slightly elevated. He has a moderate leukopenia. His CK and AST are elevated. What is the diagnosis?

A

Viral myositis due to influenza

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

A 13-year-old female with SLE and class IV LN receiving IV methylprednisolone pulsing x 3 doses/week weekly, mycophenolate mofetil, and Plaquenil. She has demonstrated clinical improvement. She reports new fatigue, myalgias, difficulty climbing the stairs. Her muscle enzymes are elevated.

What is on the differential for her new muscle weakness

A

Steroid-induced myopathy
Plaquenil-induced myopathy
Underlying SLE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

A 6-year-old male presents for evaluation of muscle weakness and markedly elevated CK in the 10,000s. On exam, he has no rashes. He has prominent calf muscles. His mother reports she has had similar symptoms. What is the diagnosis?

A

Duchenne muscular dystrophy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

A 15-year-old female presents with fatigue, hair thinning, proximal muscle weakness, and muscle cramping and enlargement in her calves. Her CK is elevated, and she has lab signs of rhabdomyolysis.

What endocrinopathy is on the differential and how could we initially evaluate for it?

A

Hypothyroid myopathy

TSH, FT4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What features may help distinguish juvenile polymyositis from JDM?

A

Age of onset: preteen-teen (median 12.1 years)

More severe illness, higher CK, more frequent falling as a sign of distal weakness, myalgias, Raynaud phenomenon, weight loss, pulmonary disease, cardiac abnormalities

Calcinosis infrequent

Need muscle biopsy to exclude other myopathies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What features may help distinguish overlap myositis from JDM/JPM?

A

More frequent Raynaud phenomenon, ILD, arthritis, sclerodactyly, periungal capillary abnormalities

Mortality is highest for overlap compared to JDM or JPM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What are the differences between malar rash in SLE vs JDM?

A

JDM malar rash lacks well-defined borders and does NOT spare nasolabial folds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What histopathologic muscle biopsy findings are seen in chronic arthritis, acute rheumatic fever, SLE, and scleroderma?

A

focal accumulation of lymphocytes, patchy fiber atrophy, and increased interstitial connective tissue but no significant vasculopthy

32
Q

What histopathologic muscle biopsy findings are seen in Sjogren?

A

muscle fiber degeneration and atrophy, sarcoplasmic degeneration, and microcyst formation

33
Q

What histopathologic muscle biopsy findings are seen in polyarteritis nodosa?

A

necrotizing vasculitis with muscle fiber degeneration and neurogenic atrophy

34
Q

What is the condition that results in painful muscle and fascial swelling followed by fibrosis, calcification, and ossification? Classic early finding is short great toes with hallux valgus.

A

Fibrodysplasia ossificans progressiva

Rare AD inflammatory disorder

Patients may present with spontaneous joint contracture or pre-osseous soft tissue lesions. Hard to diagnose until calcification occurs. Biopsy may look like malignant sarcoma. Common sites include back of neck and posterior trunk with tumorlike swellings followed by limbs. Palmar and plantar fascia may be affected. The great toes are congenitally malformed, usually short with hallux valgus. The thumbs are sometimes involved. The toe deformity is an early clinical sign to diagnosis, even before ossification. May also have cranial skeleton deformities. There is no therapy for prevention or treatment.

35
Q

What condition is associated with higher frequency of homozygosity at HLA-DQA1?

A

Multiplex myositis

36
Q

What percentage of patients will have elevated muscle enzymes?

A

80-96%

Muscle enzymes can be normal despite active disease. Degree of muscle enzyme elevation does NOT correlate with disease outcome

37
Q

What are 2 proposed biomarkers for JDM disease activity to distinguish active disease from remission and may be elevated months prior to a flare or CK elevation?

A

Galectin-9, CXCL-10

38
Q

What is the percentage of patients with JDM who have a positive ANA?

A

76%

39
Q

What is the percentage of patients with JIIMs who have an MSA?

A

40-60%

40
Q

What are classic findings on EMG for JDM?

A

Increased spontaneous and insertional activity (as evidenced by fibrillation potentials and positive sharp waves); low-amplitude short duration, polyphasic motor unit action potentials; and early recruitment

41
Q

What type of muscle (striated vs smooth) is affected in JDM?

A

Striated skeletal muscle

42
Q

What are some classic muscle biopsy findings for JDM?

A

Muscle fibers demonstrate perifascicular atrophy or necrosis, which is a/w noninflammatory capillaropathy

Variations in myofiber size due to degeneration and regeneration
Focal necrosis replaced by interstitial proliferation of connective tissue
Inflammatory exudate often present
Inflammatory cells include lymphocytes and mononuclear cells, located in perimysium and perivascularly around septae or fascicles – nondiagnostic because this can be seen in muscular dystrophies too. Also macrophages, plasma cells, mast cells, and – rarely – eos or basos
Nonspecific changes: disruption of myofibrils and tubular systems, central nuclear migration, prominent nuclei and basophilia
Immunohistochemistry shows that pDCs are one of the primary infiltrating immunophenotypes

43
Q

There are tubuloreticular inclusions seen on EM of muscle biopsy obtained from a patient with presentation suspicious for JDM. What does this signify?

A

Increased Type I interferon

44
Q

What is a predictor of a chronic course on muscle histopathology of a patient with JDM?

A

Extensive myopathic changes:

uscle degeneration and vacuolation
Sarcoplasmic pallor and necrosis
Central nuclei without basophilia
Muscle infarction correlates with chronic course, GI ulceration, and death

45
Q

What are classic findings on MRI w/wo contrast in JDM?

A

T1 weighted detects muscle atrophy and fatty infiltration with chronic disease

Subcutaneous fat signal intensity change is associated with more aggressive chronic disease and may signify increased likelihood to develop calcinosis in the future

T2 weighted imaging and fat suppression shows soft tissue edema with active disease

STIR - increased signal intensity reflects edema
Whole body MRI can even identify distal muscle edema even if the patient is asymptomatic

46
Q

What physical examination finding may suggest decreased bioavailability of oral prednisone in JDM and suggest that the patient may respond better to IV methylprednisolone?

A

Loss of nailfold capillary end-row loops

47
Q

What is the first line treatment for JDM?

A

Corticosteroids

Methotrexate

48
Q

What symptoms/signs of JDM tend to respond well to IVIG?

A

IVIG is good for persistent skin manifestations despite improvement in muscle disease

Dose: 2 grams/kg/infusion (max 70 grams)

49
Q

When would you consider addition of cyclosporine to the treatment of a patient with JDM?

A

May be used in refractory skin disease

Textbook authors reserve its use in secondary MAS

50
Q

What are some indications for cyclophosphamide use in JDM?

A

Used in severe or refractory disease: skin ulceration, severe muscle disease with dysphonia/dysphagia, GI involvement, ILD

51
Q

What are some indications for addition of mycophenolate mofetil to the treatment of a patient with JDM?

A

May be used in persistent skin disease but could be good for muscle disease too

Demonstrated improvement in both skin and muscle disease at 12 months in one study and improvement in muscle strength and decrease in steroid use at 3 months in another study

Textbook authors use in patient who don’t tolerate methotrexate

52
Q

What are some indications for the addition of Plaquenil to the treatment of a patient with JDM?

A

May be used in skin predominant disease

Textbook authors use sparingly, mostly for overlap patients because Plaquenil does not appear to have marked effect on skin rash or myositis in JDM

53
Q

What are some indications for the use of rituximab in the treatment of JDM?

A

Textbook authors use for necrotizing myopathy (anti-SRP or anti-HMGCR-positive patients) and sometimes for ILD

Rituximab in Myositis (RIM) trial - multicenter, randomized, double-blind, placebo-phase trial comparing rituximab at week 0 and 1 to rituximab at week 8 and 9

83% of patients responded to rituximab and decreased their steroid doses by week 44

No difference in time to response between early (week 0 and 1) and late (week 8 and 9) treatment arms

Presence of antisynthetase (particularly anti-Jo-1) and anti-Mi-2, juvenile onset, and lower disease damage predicted better efficacy

Reported improvement in skin disease too

No improvement in calcinosis

54
Q

What is an indication for the use of TNFi in the treatment of JDM?

A

Adalimumab, infliximab used in UK as second-line for calcinosis

Etanercept not effective and some patients got worse

55
Q

What are some indications for the use of abatacept in the treatment of JDM?

A

Refractory skin ulcers, progressive calcinosis

There is an ongoing clinical trial in refractory JDM

Bonus: Abatacept is a soluble fusion protein made of CTLA-4 and Fc portion of IgG

56
Q

What has tofacitinib been used for in the treatment of JDM?

A

Refractory skin disease and inflammatory arthropathy - case series

Amylopathic dermatomyositis intersititial lung disease - case report

57
Q

What are some non-pharmacologic treatments that should be discussed with patients with a new diagnosis of JDM?

A

Sunscreen (UVA and UVB protection, at least SPF 30)

Calcium and Vitamin D supplementation given chronic steroid use

PT, OT

58
Q

What are some complications of lipodystrophy seen in JDM?

A

Insulin resistance
Diabetes
Hypertriglyceridemia

59
Q

What fraction of patients with JDM have a monocyclic course?

A

1/3 of patients with JDM have a monocyclic course

60
Q

What fraction of patients with JDM have a polycyclic course?

A

3-30%

61
Q

In JDM, which clinical features improve faster: skin disease or muscle disease?

A

Muscle disease

62
Q

What are predictors of a longer time to remission in JDM?

A

Gottron papules at 3 months

Abnormal nailfold capillaries and rash at 6 months

63
Q

What are some common causes of death in patients with JDM?

A 
GI vasculitis leading to GI bleed or GI perforation
Progressive pulmonary disease
Progressive myositis
Progressive CV disease
Super infections
64
Q

What symptoms or distinguishing features are seen more in juvenile polymyositis (JPM) compared to JDM?

A 
more severe disease illness onset and higher CK levels
More frequent falling episodes as a sign of distal weakness
Myalgias
Raynaud phenomenon
Weight loss
Pulmonary disease
Cardiac abnormalities
Abnormal nail fold capillary pattern
Calcinosis occurs infrequently
Anasarca
65
Q

What is the incidence of JPM as a percentage of all JIIM?

A

2% of all JIIMs are JPM

22% of all JIIMs are JDM

66
Q

What are some pulmonary manifestations of JDM?

A

Aspiration pneumonia
Alveolar hypoventilation
Interstitial lung disease

67
Q

What are additional diagnostic studies useful in evaluation of pulmonary involvement in a patient with JDM?

A

PFTs - including DLCO (carbon monoxide diffusion capacity)
- can see restrictive ventilatory defects and decreased DLCO

HRCT chest - confirmatory testing since PFTs can show restrictive pattern from respiratory muscle weakness alone

You can see the following findings on HRCT chest:

  • Consolidation
  • Reticulonodular infiltration
  • Ground glass opacities
  • Peribronchovascular thickening
  • Bilateral lesions, mostly lower lobe
68
Q

What myositis specific antibodies are associated with an increased risk of developing calcinosis in JDM?

A

Anti-NXP-2 (anti-MJ)

Anti-PM-Scl

69
Q

What is an indication for bisphophanate use in a patient with JDM?

A

Treatment of calcinosis

70
Q

What are some complications of calcinosis in JDM?

A

Cellulitis
Flexion contractures – calcinosis crosses joint margins
Severe pain – if calcinosis entraps nerves
May slowly resolve with recurrent extrusion of small flecks of calcium or development of liquid Ca salts that resorb. The latter occurs with aggressive anti-inflammatory and demineralizing treatments
Exoskeleton – SQ Ca deposition along fascial planes and within muscle. Results in severe disability

71
Q

A 4 year old male presents with fatigue, diffuse arthralgias and myalgis, difficulty walking up the stairs. He is otherwise healthy and received his 4 year old vaccines recently. His CK is elevated. MRI reveals mostly unilateral proximal muscle edema in his left thigh. Muscle biopsy of his affected quad reveals a predominantly macrophagic infiltration with focal myositis with aluminum intracytoplasmic inclusions. What is the diagnosis? What is the trigger?

A

Macrophagic myofasciitis triggered by vaccine containing aluminum

72
Q

A school age male develops acute onset severe proximal calf pain and tenderness. He is otherwise healthy except for he has been out sick for a few days last week with fever, headache, and body aches. His labs look pretty good except mildly elevated ESR, moderate leukopenia, and elevated CK and AST. What is the diagnosis and treatment?

A

Post influenza myositis. Occurs 3-14 days after flu. Lasts days to weeks. Treatment supportive.

73
Q

What infection has a syndrome that mimics DM?

A

Toxoplasmosis

74
Q

What does the muscle biopsy of juvenile polymyositis (JPM) look like?

A

endomysial inflammatory infiltrate scattered throughout the muscle fascicle (in contrast to juvenile dermatomyositis [JDM], in which affected muscle fibers are typically grouped in one portion of the fascicle).

In JPM, muscle fiber size is variable, and there are usually no signs of vasculopathy. Scattered necrotic muscle fibers may be present.

75
Q

What disease has these findings on muscle biopsy?

scattered endomysial inflammatory infiltrate with little evidence of vasculopathy

A

juvenile polymyositis (JPM)

76
Q

What disease has these findings on muscle biopsy?

Rounded, hypercontracted myofibers with areas of fatty replacement

A

congenital myopathies like Duchenne muscular dystrophy

Although not specific, histologic findings in Duchenne muscular dystrophy are more likely to demonstrate “opaque” hypertrophic fibers, rounded hypercontracted myofibers, and significant replacement of muscle by fat.

Pediatric Rheumatology Board Exam (21 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions