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
What diseases may cause Raynaud syndrome?
Mixed connective tissue disease, SLE, CREST (limited form of systemic sclerosis)
Describe the color change of Raynaud phenomenon.
White (ischemia) -> blue (hypoxia) -> red (reperfusion)
Pathogenic triad of scleroderma (systemic sclerosis)?
- Autoimmunity
- Non-inflammatory vasculopathy
- Collagen deposition with fibrosis
General presenting symptoms of scleroderma?
Sclerosis of skin (puffy, taut skin, no wrinkles, with fingertip pitting) + sclerosis of other systems
Symptoms of limited scleroderma?
Skin involvement confined to fingers and face
CREST - calcinosis, raynaud, esophageal dysmotility, sclerodactyly, telangiectasias
Most common cause of osteomyelitis? Other possible causes?
S. AUREUS
S. epidermidis P. aeruginosa Pasteurella N. gonorroheae Salmonella M tuberculosis Candida
Osteomyelitis associated with sexual transmission?
N. gonorrheae
Osteomyelitis associated with puncture wounds?
P. aeruginosa
Osteomyelitis associated with sickle cell disease?
S. aureus and salmonella
Osteomyelitis associated with prosthetic joint replacement?
S. aureus and S. epidermidis
Osteomyelitis associated with vertebral involvement?
S. aureus and M. tuberculosis (Pott disease)
Osteomyelitis associated with cat/dog bites?
Pasteurella
Osteomyelitis associated with IV drug use?
S. aureus, P. aeruginosa, Candida
N. gonorrheae more commonly causes which - osteomyelitis or septic arthritis?
Septic arthritis
Most common cause of septic arthritis? Other causes?
S. AUREUS
Streptococcus
N. gonorrheae
How does septic arthritis caused by N. gonorrheae present?
Often unilateral, presents as either a purulent arthritis or a triad of polyarthralgia , tenosynovitis, and dermatitis
