Musculoskeletal 2 Flashcards
List the 4 seronegative spondyloarthropathies.
- Psoriatic arthritis
- Ankylosing spondylitis
- IBD
- Reactive arthritis
Why are spondyloarthropathies described as seronegative?
Presentation - arthritis without rheumatoid factor
What are some general presenting symptoms of spondyloarthropathies?
Morning stiffness, improves with exercise, peripheral arthritis, enthesitis (inflamed tendon insertion sites), dactylitis (sausage fingers), uveitis
What specific presenting symptoms are seen in psoriatic arthritis?
Skin psoriasis and nail lesions - asymmetric and patchy
Dactylitis, pencil-in cup deformity of DIP on X-ray
What specific presenting symptoms are seen in ankylosing spondylitis?
Symmetric involvement of spine and sacroiliac joints -> ankylosis (especially bamboo spine)
Uveitis
Aortic regurgitation
Why can ankylosing spondylitis cause restrictive lung disease?
Limited chest wall expansion with costovertebral and costosternal ankylosis
What organisms are associated with reactive arthritis?
Shigella, Salmonella
Chlamydia, Campylobacter
Yersinia
SSCCY
What is the classic triad of reactive arthritis?
Conjunctivitis
Urethritis
Arthritis (asymmetric)
“Can’t see, can’t pee, can’t bend my knee”
What are the classic symptoms of SLE?
Rash (malar or discoid), arthritis (non-erosive), fever
Serositis, hematologic disoders, oral/nasopharyngeal ulcers, disease, photosensitivity, neurologic (seizures, psychosis, etc.)
What are significant complications of SLE?
- Libman-Sacks endocarditis
2. Lupus nephritis
What are two possible symptoms caused by antiphospholipid syndrome?
Thrombosis, spontaneous abortion
What is mixed connective tissue disease?
Features of SLE, systemic sclerosis, and/or polymyositis
What are the key microscopic morphologic features of sarcoidosis?
Non-caseating granulomas
Epithelioid granulomas containing microscopic Schaumann and asteroid bodies
What are the lab findings in sarcoidosis?
Elevated ACE, elevated CD4/CD8 ratio in bronchoalveolar lavage fluid
Hypercalcemia
What are the imaging findings in sarcoidosis?
Bilateral hilar adenopathy and coarse reticular opacities
Key features of polymyalgia rheumatica?
Pain and stiffness in shoulders and hips, often with fever, malaise, weight loss
NO MUSCLE WEAKNESS
Compare the CK findings in polymyalgia rheumatic, polymyositis, and dermatomyositis.
Normal in polymyalgia, increased in the myositises
Compare the microscopic morphology of polymyositis and dermatomyositis.
P - endomysial inflammation with CD8+ T cells
D - perimysial inflammation and atrophy with CD4+ T cells
Compare the presentations of polymyositis and dermatomyositis.
P - progressive symmetric proximal muscle weakness (esp. shoulders)
D - as above + malar rash, Gottron papules (erythematous plaques over joints/bony prominences of hands), heliotrope rash, shawl and face rash, mechanic’s hands
Compare the cancers associated with MG and LEMS as paraneoplastic syndromes.
MG - thymoma
LEMS - small cell lung cancer
Most common NMJ disorder?
MG
Compare the autoantibodies seen in MG vs. LEMS.
MG - Ab against POST-synaptic ACh receptor
LEMS - Ab against PRE-synaptic calcium channels (decreases ACh release)
Compare the symptoms of MG vs. LEMS.
MG - ptosis, diplopia, weakness that WORSENS WITH USE
LEMS - proximal muscle weakness that IMPROVES WITH USE, autonomic symptoms
Compare the response of MG vs. LEMS to AChE inhibitors.
MG - improves (edrophonium/tensilon test)
LEMS - minimal effect
