pathophys Flashcards
what 5 joints does OA usually effect? gender predilection?
- hands, PIP and DIP, CMC of thumb (women)
- knees (women)
- hips (men)
- feet (MTP 1)
- spine
what joints does OA secondary to DM neuropathy affect?
MTPs 2-5 also
what two genetic alleles predispose to RA?
HLA-DRB1
PTPN22
what antibodies are most specific to RA? what other antibodies are associated with RA?
anti-CCP
rheumatoid factor
what immune response is implicated in RA?
TH1 and TH17
which joints in the hand does RA affect? what joints may it affect that aren’t usually affected in OA?
MCP and PIP, not DIP
shoulder and ankle
what is different between the spinal involvement of OA and RA?
RA: only cervical spine with risk of spinal cord compression
what confers genetic predisposition to SLE?
HLA-DR2
HLA-DR3 weakly
C1q, C2 or C4 complement deficiency
which antibodies are specific to SLE and what are they associated with?
anti-dsDNA: nephritis
anti-SM: none
antiphospholipids: clotting, spontaneous abortions
what resembles RA but shows no erosions, deformities are reducible?
Jaccoud’s-like arthropathy: arthritis in SLE with history of rheumatic fever
what T cell response is seen in scleroderma?
TH2: alternative macrophage activation and collagen deposition
what suggests autoimmune etiology with Raynaud’s?
widened capillary loops in nail-bed
what antibodies are associated with diffuse SSc, limited SSc, and scleroderma renal crisis?
diffuse SSc: anti-topoisomerase 1 (anti-Scl70)
limited SSc: anti-centromere
renal crisis: anti-RNA polymerase III
what antibody is associated with overlap syndrome (SLE, scleroderma, MCTD)?
anti-U1-RNP
what is the most common cause of death in diffuse SSc?
interstitial lung disease, PAH
what is the clinical presentation of limited SSc
CREST calcinosis Raynaud esophageal dysmotility sclerodactyly telangiectasia
what disease characteristics are seen in MCTD? what is the most common cause of death?
lupus, scleroderma, myositis
PAH
what antibodies are somehwat sensitive but not specific to Sjogren’s? which are specific?
ANA and rheumatoid factor
anti-Ro (SSA) and -La (SSB)
what is the negative predisposition for spondyloarthropathies?
HLA-B27
how does reactive arthritis present? what is the genetic predisposition?
HLA-B27
- arthritis
- urethritis
- conjuncitivitis
which specific cytokine is increased in psoriatic arthritis?
IL-18
what disease is anti-Jo-1 antibody associated with?
polymyositis and dermatomyositis with arthritis
what other organ is infected in 70% of inflammatory myopathies?
interstitial lung disease
what should be tested for following diagnosis of inflammatory myositis, esp. dermatomyositis?
malignancy in 12%
what inflammatory cells are implicated in DM vs PM/IBM?
DM: CD4, macros, dendritic cells
PM/IBM: CD8 and macros
with arthritis, what differentiates the rashes of dermatomyositis and SLE?
DM rash affects knuckles, SLE spares knuckles and affects phalanges
DM doesn’t spare nasolabial folds
what is cracking hyperkeratosis of skin over fingers with arthritis of those small joints a sign of?
dermatomyositis or polymyositis
how can polymyositis be clinically differentiated from inclusion body myositis?
IBM is resistant to glucocorticoid treatment
how can inflammatory myopathies and polymyalgia rheumatica be differentiated in lab?
myopathies: increased CPK
polymyalgia: elevated ESR
