Summary
Polyarthritis and oligoarthritis are conditions characterized by swelling and/or pain affecting multiple joints. Causes are diverse and include infections, autoimmune and inflammatory conditions, crystal deposition, and osteoarthritis. The most common causes of polyarthritis are hand osteoarthritis and rheumatoid arthritis. Clinical evaluation involves a focused history and physical examination to assess joint involvement patterns and pain characteristics and evaluate for synovitis and extra-articular symptoms. Synovitis and/or extra-articular features often suggest an inflammatory or autoimmune cause. Diagnosis varies based on the suspected condition but may include laboratory studies (e.g., CBC, inflammatory markers) and imaging (e.g., x-rays) of affected joints. Additional studies and specialist referral may be considered based on clinical suspicion. Management varies depending on the underlying cause and may include symptomatic treatment, disease-modifying agents, and/or treatment of infection.
Etiology
Conditions are listed under their most common presentation.
Oligoarthritis (≤ 4 joints) [1][2][3]
- Infectious (e.g., Lyme disease)
- Autoimmune or inflammatory
-
Crystal deposition (rare)
- Gout
- Calcium pyrophosphate deposition (CPPD) disease (e.g., pseudogout)
- Other: secondary osteoarthritis (posttraumatic arthritis)
Polyarthritis (≥ 5 joints) [1][2][3]
-
Infectious
- Viral arthritis (e.g., due to parvovirus B19, HCV, HBV, or HIV)
- Rheumatic fever
- Infective endocarditis (immune complex-mediated)
- Disseminated gonococcal infection
- Autoimmune or inflammatory
-
Other
- Hand osteoarthritis
- Paraneoplastic arthritis (e.g., due to leukemia, lymphoma, or multiple myeloma) [1][4]
- Drug-induced arthritis (e.g., due to quinolones, DPP-4 inhibitors, or aromatase inhibitors) [1][2][4]
The most common causes of polyarthritis are hand osteoarthritis and rheumatoid arthritis. [2]
Common causes by pattern and course
Oligoarthritis and polyarthritis by pattern and course | ||
---|---|---|
Symmetrical | Asymmetrical | |
Acute (< 6 weeks) |
| |
Chronic (≥ 6 weeks) |
|
|
Clinical evaluation
Focused history [2][4][5]
-
Joint symptoms
- Onset and duration
- Number of affected joints
- Specific joints affected
- Small (e.g., MCPs, proximal interphalangeal joints) vs. large (e.g., knees, shoulders)
- Axial skeleton involvement: See also “Seronegative spondyloarthropathies.”
- Inflammatory features: morning stiffness (including duration), gelling, symptoms of synovitis (e.g., warmth, erythema, swelling, tenderness)
- Pattern of involvement
-
Extra-articular and/or systemic symptoms
- Systemic: fever, chills, fatigue, weight loss
- Skin: rashes, nodules, nail changes
- Eyes: redness, pain, vision changes
- Gastrointestinal: abdominal pain, diarrhea, mouth ulcers
- Genitourinary: dysuria, urethral discharge
- Respiratory: dyspnea, cough, pleurisy
- Neurological: weakness, paresthesia
- Other: Raynaud phenomenon, sicca syndrome
-
Past medical history: potential causes of polyarthritis or oligoarthritis
- Recent infectious diseases (e.g., urethritis, acute pharyngitis)
- Diagnosed autoimmune conditions (e.g., SLE, inflammatory bowel disease, psoriasis)
- Cancer
- Medications: medication review with a focus on new medications
- Family history: autoimmune conditions (e.g., rheumatoid arthritis, ankylosing spondylitis, SLE)
- Social history: intravenous drug use, STIs, exposures (e.g., tick bites, recent travel)
Infectious causes of polyarthritis (e.g., viral arthritis, rheumatic fever) are typically acute in onset. [2]
Focused examination [1][2][3][4]
Musculoskeletal examination
- Inspection
- Palpation
-
Range of motion (active and passive)
- Degree of reduction
- Pain with movement
-
Joint assessment
- Number of affected joints (i.e., oligoarthritis vs. polyarthritis)
- Peripheral (e.g., hands, feet, knees) vs. axial (e.g., spine, sacroiliac joints)
- Predominant joints affected (i.e., small or large joints)
- Pattern of involvement (i.e., migratory, additive, or intermittent)
- Symmetrical vs. asymmetrical arthritis
Synovitis is a typical feature of inflammatory polyarthritis or oligoarthritis (e.g., infections, autoimmune conditions, gout, CPPD disease) but is usually mild or absent in patients with osteoarthritis.
Thoracolumbar and/or sacroiliac joint involvement commonly occurs in ankylosing spondylitis, psoriatic arthritis, enteropathic arthritis, and reactive arthritis but is rare in rheumatoid arthritis. [2]
Extra-articular examination
- Skin: rashes, nodules, ulcers, nail changes (e.g., pitting, onycholysis)
- Eyes: conjunctival injection, signs of uveitis (e.g., ciliary flush, photophobia)
- Oropharynx: ulcers, dryness
- Neck: lymphadenopathy, palpable thyroid gland
- Cardiovascular: heart murmurs, pericardial friction rub
- Lungs: pathological breath sounds
- Abdomen: tenderness, organomegaly
- Neurological: motor function examination, focused sensory examination
Extra-articular features suggest an autoimmune or inflammatory cause of oligoarthritis or polyarthritis.
Diagnostics
General principles
- In most patients with oligoarthritis or polyarthritis, a probable cause is identified during clinical evaluation.
- Tailor the diagnostic approach to the suspected condition (e.g., diagnostics for rheumatoid arthritis).
- For undifferentiated arthritis, obtain laboratory studies and imaging listed below.
- Early referral to specialists (e.g., rheumatology, infectious diseases) improves clinical outcomes.
Approximately 30% of patients with early inflammatory arthritis are eventually diagnosed with rheumatoid arthritis. [6]
Initial studies [2][3][5]
Laboratory studies
- CBC: may show leukocytosis, anemia of chronic inflammation associated with a systemic condition
- Inflammatory markers (nonspecific study): may be elevated in infectious, malignant, autoimmune, or chronic conditions
- BMP: ↑ creatinine and BUN in systemic conditions with kidney involvement (e.g., SLE, systemic sclerosis)
- Liver chemistries: may be elevated in viral hepatitis or in autoimmune or inflammatory conditions with liver involvement
- Urinalysis: Active urine sediment and/or proteinuria may be present in systemic conditions with renal involvement (e.g., SLE).
- Serology: serologic testing in RA, ANAs for SLE in patients with constitutional symptoms and extra-articular features
Carefully consider the clinical indication before requesting any diagnostic study to avoid false positives; autoantibodies may be elevated in healthy individuals. [1]
X-rays
Obtain x-rays of the affected joints.
-
Hand x-ray
- See “Imaging studies” in “Rheumatoid arthritis.”
- See “Imaging studies” in “Osteoarthritis.”
- See “Imaging studies” in “Psoriatic arthritis.”
- Spine x-ray: if spinal involvement is suspected (e.g., in psoriatic arthritis, ankylosing spondylitis)
- Chest x-ray: in patients with pathological breath sounds, dyspnea, or other cardiopulmonary signs
Additional studies [2][3][5]
Obtain additional studies based on the suspected cause.
- Serology, e.g.:
-
Additional imaging studies, e.g.:
- Joint ultrasound (e.g., MCP joints): to assess for subclinical synovitis if early rheumatoid arthritis is suspected [1][7]
- MRI of affected joints: if osteomyelitis is suspected in septic arthritis
- HRCT chest: if pulmonary involvement is suspected in systemic conditions
- Echocardiography: to assess for conditions to assess for cardiac involvement (e.g., endocarditis, pericarditis)
Common causes
Common causes of oligoarthritis and polyarthritis [2][3][4] | |||
---|---|---|---|
Condition | Characteristic clinical features | Diagnostic findings | Management approach |
Rheumatoid arthritis |
|
|
|
Hand osteoarthritis |
|
|
|
SLE |
|
|
|
Viral arthritis |
|
|
|
Psoriatic arthritis |
|
|
|
Reactive arthritis |
|
|
|
Enteropathic arthritis |
|
|
|
Ankylosing spondylitis |
|
|
|
Mimics
- Systemic conditions [2]
- Other