Monoarticular arthritis

Septic Arthritis

Gonococcal Arthritis

Healthy, young sexually active adults

Women > men

Suppurative monoarthritis (may be preceded by polyarthralgias)

Knee, wrist, ankle

Arthritis-Dermatitis Syndrome

-Triad: dermatitis, tenosynovitis, migratory polyarthritis (hematogenous spread of bacteria and immune complexes)

-Skin lesions: scattered small painless erythematous macules or petechiae-->pustular -->necrotic lesions

-Transient painful extensor tenosynovitis (writs, hands, ankles)

-Asymmtric polyarthralgia of extremity joints

DiagnosisCx everything - jt, mucosal surfaces, lesions

TreatmentCTX 1gIV qd OR

Cefotax 1g q8

Empirically treat Chlamydia

Nongonococcal Arthritis

Fulminant presentation (abrupt, swelling, toxicity and fever) unless elderly

-Hematogenous

-Contiguous

-Direct traumatic implantation

-Postop

CausesBacterial

Mycobacterial

Spirochete (lyme, syphilis)

Fungal

VIral (HIV, Hep B, Rubella, etc)

Postinfectious

DiagnosisSynovial fluid aspiration

Cx - if only one test, use BCx bottles (may enhance yield)

Grm stain - 80% positive in gram-positive infxn; less sens in gram-negative

Cell count with dif - >50,000-150,000; PMN > 90%

TreatmentPCN-ase resistant synthetic PCN:

Nafcillin 1-2g

Cefazolin 1-2g

AND

3rd gen ceph

OR

Vanc*

• new evidence suggests significantly increased rate of MRSA septic arthritis

• • cell counts are as low as 20,000 in MRSA Cx + synovial fluid

Crystal-Induced Monoarthritis

1. Gout

Monosodium urate crystals - needle shaped negative birefringence

Swelling, redness, warmth evolving rapidly over hours todays

First MTP (podagra) 60% > ankle > midfoot > knee

May have constitutional complaints

Precipitants: purine-rich food, EtOH, trauma, chemo, diueretic use, RI

DiagnosisSynovial fluid aspiration (above)

Note: serum uric acid levels unhelpful; ESR/CRP may be elevated

TreatmentNSAIDS eg Naproxen 500mg po bid x 3d and taper over 4-7d

Colchicine 0.6mg po qh x 3 or 1mg PO f/b 0.5mg q1h until relif, GI upset, or 8mg max

Can give 1-2mg IV over 30mins

• No further doses after initial load

• • avoid NSAIDS, Colchicine in RF

Steroids

-Prednisone 40-60mg po qd x 3d f/b 7d taper

1. Pseudogout

Traumatic

1. Fracture
2. ligamentous
3. Overuse

Ischemic

1. Avascular necrosis
2. Decompression illness
3. Spontaneous osteonecrosis
4. pain in abscence of trauma
5. femoral head, medial conyle of knee

Hemorrhagic

1. Posttraumatic
   1. Joint aspiration if tense
   2. RICE
2. Hemophilia
3. Systemic anticoagulation

Neoplastic

1. Mets
2. Osteochondroma
3. Osteoid osteoma
4. Pigmented villonodular synovitis

Systemic Disease

1. Remote infxn, infectious endocarditis
2. Rheumatic fever
3. Seronegative (no RF) spondyloarthropathies (AS, IBS, psoriatic, reactive or Reiter's)
4. Rheumatoid arthritis, SLE
5. Sarcoidosis, amyloidosis

Periarticular

these conditions mimic joint involvement...

1. Cellulitis
2. Tendonitis
3. Bursitis

Peds

don't forget about...

1. Acute Transient Synovitis
   1. Children 3-10yo
   2. 1-3 wks after viral illness
   3. Self-limited
2. SCFE (portly pubescent)
3. Leff-Calve-Perthes (young school-age children)

See Also

Pseudogout

Gout

Source

H-N