Monoarticular arthritis Flashcards
Differentiate between arthralgia and arthritis
Arthralgia = joint pain
Arthritis = evidence of inflammation or damage (swelling/effusion, tenderness, warmth, discoloration)
What are the major categories you consider when presented with a patient who is complaining of isolated joint pain and evidence of inflammation
Infection Crystalline Trauma Osteoarthritis Hemarthrosis --> Trauma Clotting disorder or anticoagulation Pigmented villonodular synovitis Rheumatic disease
What kinds of infection can cause arthritis?
Bacterial Fungal Mycobacterial Viral Spirochete
What are examples of crystalline arthritis?
Gout Pseudogout Hydroxyapatite Calcium oxalate Lipid
What are examples of systemic rheumatic diseases that cause arthritis?
Rheumatoid arthritis Spondyloarthropathy SLE Sarcoidosis Reactive arthritis
Components of history
Changes with rest and activity
Prior trauma
Morning stiffness
Systemic symptoms
Has the patient ever experienced anything like this in the past
What are the patient’s other medical problems, what medications is the patient on (example – is the patient on anticoagulation?)
Components of physical exam
Vital signs (fever?) General exam Joint exam Rubor (redness) Calor (warmth) Dolor (pain) Tumor (swelling)
Relative contraindications to arthrocentesis
Uncontrolled bleeding disorder
Anticoagulation, risk of bleeding is low with INR < 3
Overlying cellulitis/ skin or soft tissue infection
Fracture or prosthetic joints are usually not aspirated by Rheumatologists
Local side effects of arthrocentesis
Infection
Bleeding
Post injection flare, skin hypopigmentation, fat/ skin atrophy, tendon rupture
At what level of WBCs seen under microscope is considered inflammatory?
2000
this means you cannot r/o infection
What are lab tests to consider?
Infection Blood culture Cervical/urethral culture Viral serologies (e.g. HIV, HCV) Lyme antibody Inflammatory RF CCP Antibody ESR, CRP Gout Uric acid
What are appropriate imaging/testing?
Xray -Evaluate for fracture, tumor, osteoarthritis, or other bone pathology Ultrasound MRI -Soft tissue, Cartilage
Common errors of diagnosis
Arthralgia vs. Arthritis
Presence of crystals and/or known rheumatic disease does not rule out infection!
Normal serum uric acid does not rule out gout
Negative gram stain and culture does not rule out infection
If history of joint replacement or hardware – call orthro!
Indications for ortho referral
Traumatic monoarthritis
Emergencies: suspect infection or septic joint, constitutional symptoms
indications for rheum refer
New or unexplained joint swelling
Monoarthritis unresponsive to treatment
Suspected inflammatory arthritis or crystalline disease
