Lab Testing in Rheumatic Diseases Flashcards
Polymyalgia rheumatica and Giant Cell Arteritis can both be monitored using __
ESR (acute phase reactant)
Where is CRP synthesized and what can increase it? Greater than __mg/l is considered inflammatory?
- synthesized in liver and can be increased by proinflammatory cytokines
- greater than 8mg/l is inflammatory
What Acute Phase Reactant increases with age and is higher in F>M
ESR
Does ESR or CRP rise/fall more rapidly?
CRP
What is produced by B cells in synovial joints in rheumatoid arthritis patients? This autoantibody targets ____.
Rheumatoid Factor. Tagets Fc portion of IgG
RF is present in ___% of RA pts.
RF is present in ___% of “nodular” RA pts.
70-80%
100%
Cutoff valve for positive RF in:
- ELISA
- latex fixation
- ELISA: RF > 45IU/ml
- latex fixation: RF > 1:80
What two tests have 99.5% specificity for RA?
Anti CCP and positive RF
homogenous pattern ANA - caused by?
drug induced lupus
postive ANA can occur in what four types of pts?
normal (20-30%), RA, CTD (connective tissue disease?), malignancy
Rim pattern ANA indicates…
anti DS DNA
Speckled anti SSA/B ANA indicates…
Sjögren syndrome
Anticentromere antibody indicates…
scleroderma
Criteria for SLE
SOAP MD BRAIN
- Serositis (inflammation in synovial fluid)
- Oral ulcers
- Arthritis
- Photosensitivity
-Malar rash, Discoid rash
- Blood - all low (anemia, thrombo/leukopenia)
- Renal
- ANA
- Immunologic (DS DNA)
- Neurologic
***Define hematologic manifestations of SLE
– Hemolytic anemia with reticulocytosis OR
- lymphopenia less than 1500
- leukopenia less than 4,000
- thrombocytopenia less than 100,000
Antistreptolysin O antibody (ASO titer) and anti DNAase B titers indicate evidence of preceding ___ infection.
evidence of preceding group A streptococcal infection
Acute Rheumatic Fever; polyarticular
strep often affects what parts of the body?
large joints (asymmetric) Post-strep Reactive Arthritis effects SMALL joints SYMMETRICALLY
These tests indicate ___:
CBC indicating hemolytic anemia, leukopenia and false positive RPR (reactive plasma reagin - syphilis)
SLE
These tests indicate ___:
Positive anti‐CCP, elevated ESR and elevated rheumatoid factor level
Rheumatoid arthritis
alcohol promotes increased ___ production and decreased excretion
urate
attacks MTP, has tophi
gout
tx of acute gout (3)
NSAIDs, colchicene, steroids
tx of chronic gout (2)
XO inhibitors, Probencid (increased renal excretion)
What imaging study of rheumatic disease has:
– Poor visualization of soft tissue
– (RA) symmetrical involvement of MCP, periarticular
osteopenia, EROSIONS in late disease
radiography - digital radiographs have high spatial resolution
– Plane radiographs may not detect early arthritic disease
What imaging study of rheumatic disease:
– Aid in injecting/aspirating joint
– No radiation
– sensitive for SOFT TISSUE abnormalities (SYNOVITIS, TENDONITIS, BURSITIS) and erosions
Ultrasonography
What imaging study of rheumatic disease:
– is useful for soft tissue abnormalities; good for spine, SI, synovitis, tenosynovitis, erosions
– Gadolinium contrast taken up in inflamed synovium (thickened pannus) IV gadolinium can cause nephrogenic systemic fibrosis (NSF) in patient with kidney disease
MRI
**GADOLINIUM TOXICITY - use CT if you can
What imaging study of rheumatic disease is best forBONY ABNORMALITIES (trabecular, cortical bone), erosions, fractures, degenerative or inflammatory arthritis
CT
Number of Joints Involved •Mono‐ •Oligo‐ •Pauci‐ •Poly‐
- Mono‐ arthritis
- Oligo‐ 3 or more
- Pauci‐ 5 or more
- Poly‐ more than 6
**What rheumatic disease affects MCPs and PIPs?
Rheumatoid arthritis
**What rheumatic disease affects knees, DIP, cervical and lumbar?
Osteoarthritis
Three types of swelling.
bony, effusion, soft tissue
define types of effusion swelling
synovial fluid (infl/non-inflam), pus, blood
swan neck:
looks like ___
indicates ___
hyperextension of PIP
advanced RA deformity
boutonniere:
looks like ___
indicates ___
hyperF of PIP
advanced RA deformity
name 5 arthritic syndromes
Syndromes •Arthritis‐ Dermatitis •Arthritis‐ Bowel •Arthritis‐ Pulmonary •Arthritis‐ Endocrine •Arthritis‐ Ophthalmologic
name causes of inflammatory bowel disease and Reactive arthritis that can cause arthritis
- Inflammatory Bowel Disease - Ulcerative Colitis, Crohn’s Diseasem Behcet’s
- Reactive Arthritis - Bowel Infection
**4 bowel infections that can cause reactive arthritis
Salmonella, shigella, campylobacter, Yersinia (N. gono/Chlamydia)
Name two endocrine disorders that can result in respective arthrtities
- Thyroid - carpal/tarasal tunnel syndrome
2. Diabetes - charcot’s and cheiroarthropathy (thiickened hand/skin that mimics scleroderma)
cytoid bodies and vasculitis result in…
retinopathy (arthritis-ophthalmologic)
dactylitis indicates
reactive arthritis
Sjogrens, SLE, and healthy, >60 years old - all can have false positive ___?
RF
Anti-CCP has greater specificity or sensitivity than RF?
specificity
Joint aspiration: 200-2,000 = ?; 2000-50,000 = ?; 50,000+ = ?
200-2,000 = noninflammatory 2000-50,000 = inflammatory (cloudy) 50,000+ = septic (cloudy, opaque)
causes of drug induced lupus
phenytoin, hydralazine
