Clinical Approach to Patient with Joint Pain I and II Flashcards
- What is the most common location of arthritis?
2. What % of adults have some form of self-reported MD diagnosed arthritis?
- back and spine
2. 22%
- What are some general clinical characteristics of arthritis?
- What is it called if its inflammatory?
- How is the disease defined?
- What are findings are important?
- Pain and stiffness in a joint
- synovitis
- distribution and chronology
- presence of extra-articular findings are important
Acute Monoarticular Arthritis
- Time course
- Etiologies (6)
- about 7 days or fewer in duration; can go out to 14
- Septic (most urgent to diagnose)
- Crystal induced (most common, not urgent)
- Trauma
- Hemorrhage- may not be obvious; check for anticoagulants
- Mechanical (occupation/weight)
- Atypical polyarticular
Acute Monoarticular Arthritis
Extra-artciular clues in Sepsis (4)
5. What can also cause inflammation?
- fever and shaking chills
- Cutaneous clues
- Tophi
- Mucosal involvement
- Gout
Synovial Fluid analysis in acute monoarticular arthritis
1. How important is it?
2. What does it mean if there are 200 WBCs?
3. What does it mean if there are 2000 WBCs and 25% or fewer are PMNs?
4, What does it mean if there are 2000 WBCs and 50% or greater PMNs?
5. Other tests that can be done
- VERY, single most important test for making correct diagnosis
- fluid is normal
- non-inflammatory
- may be inflammatory
- Gram stain, culture, crystals
What kind of crystals can cause gout? What does each look like under microscope (2)
- Sodium Urate crystals: needle shaped that may be w/in neutrophil; changes from blue –> yellow on polarized microscopy
- Calcium pyrophosphate: blunt ended crystal with weak positive birefringence
What tests are not that helpful?
- Radiology- can show demineralization, both gout and sepsis do this
- Bloodwork (NEVER a substitute for SF);
Uric acid- doesn’t correlate with presence of gout
Leukocytosis- can be in gout and sepsis
Blood cultures- can show sepsis
Gout incidence
- Which gender tends to have more gout?
- When does the other gender catch up?
- why?
- males
- females approach male incidence after menopause,
- estrogen promotes urate excretion in the urine
Gout Mechanism/ Pathogenesis
- How is IL-1 upregulated?
- What does IL-1 do?
- uric acid crystals are ingested by macrophages, which release IL-1
- recruits neutrophils
Gout Therapy
- Why isn’t Colchicine used?
- Natural course of disease
- NSAIDs aren’t used much. why?
- Short term
- Long term treatment & mechanism
- Side effect is diarrhea, which is bad with gout
- self-limited
- decrease renal function, so you excrete less uric acid
- large dose corticosteroids
- Allopurinol- inhibits Xanthine Oxidase
Chronic Monoarticular Arthritis
- Time duration
- Differential Diagnosis
- about 2 months
- Degenerative Joint Disease (Osteoarthritis)
- Mechanical Internal Derangement (like a meniscus tear)
- Chronic infection
- Joint Neoplasm (rare)
- Pigmented Villonodular synovitis
- Rheumatoid arthritis (rare)
- Idiopathic
Synovial Biopsy in Chronic Monoarticular Arthritis
- How does it compare to Synovial Fluid?
- What does it help ID/rule out? (4)
- usually not better than it, good for some things
- Neoplasm
Infection (especially fungal)
Pigmented Villonodular synovitis
Sarcoidosis
Acute Polyarthritis
- How many joints?
- How long?
- Differential Diagnosis
- more than 4
- less than 8 weeks duration
- Acute Rheumatic Fever
Gonococcal arthritis
Post-viral arthritis (common)
Lyme arthritis
Immune complex arthritis
Parvovirus
- Which adult population is at risk?
- What causes arthritis?
- Disease course
- People exposed to little kids (elementary school teachers)
- Ab cross-reactivity (?)
- usually self-limited
How can you differentiate between these 3 causes of acute polyarthritis?
- Rheumatic fever
- Borrelia
- Gonococcal
- true migratory arthritis, unique skin lesion (only present in 10%)
- Geography, season, and unique skin lesion (erythema migrans; 90-95% will have it)
- skin lesions