Musculoskeletal, Skin, and Connective Tissue- Phatology (2)

Question 1

Systemic juvenile idiopathic arthritis

• Ocurrs in
• Presentation
• Labs
• Treatment

Answer 1

In < 12 year olds.

Presents with daily spiking fevers, salmon-pink macular rash, uveitis, and arthritis (commonly 2+ joints).

Labs: leukocytosis, thrombocytosis, anemia, ESR, CRP.

Treatment: NSAIDs, steroids, methotrexate, TNF inhibitors

Question 2

Sjögren syndrome

• Ocurrs in
• Findings

Answer 2

women 40–60 years old

Findings:
ƒƒ Inflammatory joint pain
ƒƒ Keratoconjunctivitis sicca 
ƒƒ Xerostomia 
ƒƒ Presence of antinuclear antibodies, rheumatoid factor, SS-A (anti-Ro) and/or SS-B (anti- La)
ƒƒ Bilateral parotid enlargement

Question 3

Septic arthritis

• Etiology
• Presentation

Answer 3

S aureus, Streptococcus, and Neisseria gonorrhoeae are common causes.

Affected joint is swollen, red, and painful. Synovial fluid purulent (WBC > 50,000/mm3).

Question 4

Gonococcal arthritis

Answer 4

STI that presents as either purulent arthritis (eg, knee) or triad of polyarthralgia, tenosynovitis (eg, hand), dermatitis (eg, pustules).

Question 5

Seronegative spondyloarthritis

• HLA
• Types
• Clinical features

Answer 5

Strong association with HLA-B27.

Subtypes (PAIR): psoriatic arthritis, Ankylosing sponndilitis, IBD, Reactive athritis

share variable occurrence of inflammatory back pain, peripheral arthritis, enthesitis, dactylitis, uveitis.

Question 6

Psoriatic arthritis

Answer 6

Associated with skin psoriasis and nail lesions. Asymmetric and patchy involvement. Dactylitis and “pencil-in-cup” deformity of DIP on x-ray

Fewer than 1 ⁄3 of patients with psoriasis.

Question 7

Ankylosing spondylitis

Answer 7

Symmetric involvement of spine and sacroiliac joints Ž ankylosis (joint fusion), uveitis, aortic regurgitation. Bamboo spine (vertebral fusion).

Question 8

Reactive arthritis

Answer 8

Formerly known as Reiter syndrome. 
Classic triad:
ƒƒConjunctivitis
ƒƒUrethritis
ƒƒ Arthritis

Shigella, Yersinia, Chlamydia, Campylobacter, Salmonella

Question 9

SLE criteria

Answer 9

RASH OR PAIN:
Rash (malar or discoid)
Arthritis (nonerosive)
Serositis (eg, pleuritis, pericarditis)
Hematologic disorders (eg, cytopenias)
Oral/nasopharyngeal ulcers (usually painless)
Renal disease
Photosensitivity
Antinuclear antibodies
Immunologic disorder (anti-dsDNA, anti-Sm, antiphospholipid)
Neurologic disorders (eg, seizures, psychosis)

Question 10

Antiphospholipid syndrome criteria

Answer 10

Diagnose based on clinical criteria:

• history of thrombosis (arterial or venous)
• spontaneous abortion along

laboratory findings:

• lupus anticoagulant
• anticardiolipin
• anti-β2 glycoprotein antibodies.

Question 11

Mixed connective tissue disease

Answer 11

Features of SLE, systemic sclerosis, and/or polymyositis.

Associated with anti-U1 RNP antibodies (speckled ANA).

Question 12

Polymyalgia rheumatica

• Clinical features
• Epidemiology
• Labs
• Treatment

Answer 12

Pain and stiffness in proximal muscles, often with fever, malaise, weight loss. Does not cause muscular weakness.

More common in women > 50 years old; associated with giant cell (temporal) arteritis.

High ESR, high CRP, normal CK.

Rapid response to low-dose corticosteroids

Question 13

Fibromyalgia

• Occurs in
• Clinical features
• Treatment

Answer 13

Women 20–50 years old.

Chronic, widespread musculoskeletal pain associated with “tender points,” stiffness, paresthesias, poor sleep, fatigue, cognitive disturbance.

Treatment: regular exercise, antidepressants (TCAs, SNRIs), neuropathic pain agents

Question 14

Polymyositis/dermatomyositis

• Antibodies
• Treatment

Answer 14

High CK, ⊕ ANA (nonspecific), ⊕ anti-Jo-1 (histidyl tRNA synthetase) (specific), ⊕ anti-SRP (specific),
⊕ anti-Mi-2 (specific) antibodies.

Both disorders associated with interstitial lung disease.

Treatment: steroids followed by long-term immunosuppressant therapy (eg, methotrexate).

Question 15

Polymyositis

Answer 15

symmetric proximal muscle weakness, characterized by endomysial inflammation with CD8+ T cells. Most often involves shoulders.

Question 16

Dermatomyositis

Answer 16

Similar to polymyositis, but also involves malar rash, Gottron papules, heliotrope rash, “shawl and face” rash, darkening and thickening of fingertips and sides resulting in irregular, “dirty”-appearing marks. risk of occult malignancy.

Perimysial inflammation and atrophy with CD4+ T cells.

Question 17

Myasthenia gravis

• Phatophysiology
• Clinical features
• Association

Answer 17

Autoantibodies to postsynaptic ACh receptor

Ptosis, diplopia, weakness. Worsens with muscle use

Thymoma, thymic hyperplasia

*Improvement after edrophonium (tensilon) test

Question 18

Lambert-Eaton myasthenic syndrome

• Phatophysiology
• Clinical features
• Association

Answer 18

Autoantibodies to presynaptic Ca2+ channel

Proximal muscle weakness, autonomic symptoms.
Improves with muscle use

Small cell lung cancer

Question 19

Raynaud phenomenon

Answer 19

Raynaud disease when 1° (idiopathic),

Raynaud syndrome when 2° to a disease process

Question 20

Scleroderma (systemic sclerosis)

• Physiophatology
• Clinical features

Answer 20

Triad of autoimmunity, noninflammatory vasculopathy, and collagen deposition with fibrosis. 75% female

Commonly sclerosis of skin, manifesting as puffy, taut skin without wrinkles, fingertip pitting. Can involve other systems, eg, renal, pulmonary, GI, cardiovascular.

Question 21

Diffuse scleroderma

Answer 21

widespread skin involvement, rapid progression, early visceral involvement.

Associated with anti-Scl-70 antibody (anti-DNA topoisomerase I antibody).

Question 22

Limited scleroderma

Answer 22

Limited skin involvement confined to fingers and face.

CREST syndrome: Calcinosis cutis, anti-Centromere antibody, Raynaud phenomenon, Esophageal dysmotility, Sclerodactyly, and Telangiectasia.