Septic arthritis

Gonococcal Arthritis

Healthy, young sexually active adults

Women > men

Suppurative monoarthritis (may be preceded by polyarthralgias)

Knee, wrist, ankle

Arthritis-Dermatitis Syndrome

Diagnosis

-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

Treatment

CTX 1gIV qd OR

Cefotax 1g q8

Empirically treat Chlamydia

Nongonococcal Arthritis

Background

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

-Hematogenous

-Contiguous

-Direct traumatic implantation

-Postop

Causes

Bacterial

Mycobacterial

Spirochete (lyme, syphilis)

Fungal

VIral (HIV, Hep B, Rubella, etc)

Postinfectious

Diagnosis

Synovial 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%

Treatment

PCN-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

See Also

Monoarticular Arthritis

Background

• Def: inflammation of a synovial membrane with purulent effusion into the joint capsule
• usually affects monoarticular joints (the knee is most commonly affected in adults and the hip in children)
• Relatively rare disease however because it can quickly destroy the joint or lead to osteomyelitis, fibrous ankylosis, sepsis, or even death it is important to catch and treat promptly
• Frequency is ~20,000 cases in USA/year (may be higher in pts with immunologic disorders (RA, SLE))
• M>F predominance, usually in patients >65 years
• Etiology is usually bacterial, divided into gonococcal or nongonococcal groups
• staph and strep are most common nongonococcal causes
• consider different organisms in children, IV drug users, and those with prosthetic joints

Diagnosis

• may be difficult to diagnose in early stages
• patient typically presents with fever and a warm, red, painful, swollen joint with decreased range of motion even passively
• confirm diagnosis with work up

Work-Up

• CBC
• ESR
• Blood Cultures
• Gonorrhea culture (urethral/cervical/pharyngeal/rectal)
• Arthrocentesis with synovial fluid analysis
• infected fluid characteristics:
• large amount (>3.5 mL)
• turbid in appearance
• decreased viscosity
• 15,000->200,000 leukocytes/cubic cm
• 50-100% PMNs
• Poor mucin clot
• glucose >40mg/100mL less than plasma glucose
• Positive culture
• Plain films (often normal but may show widening of joint space or evidence of osteomyelitis)
• Ultrasound (can show joint effusion, extent of disease, and may help differentiate from other conditions)

DDx

• toxic synovitis
• abscess
• cellulitis
• primary rheumatologic disorder (i.e. vasculitis)
• iatrogenic
• reactive arthritis (post infectious)

Treatment

• drainage of the joint
• IV Antibiotics
• generally Oxacillin or Nafcillin with a cephalosporin (ceftriaxone, feotaxme, ceftizoxime) will cover
• add vancomycin if you suspect MRSA
• in IVDA patients use IV aminoglycoside + antipseudomonal cephalosporin
• patients with prosthetic joints are at higher risk of MRSA, MRSE, Enterobacteriaceae, and Pseudomonas
• consider gonococcal infection in young sexually active patients (treat with ceftriaxone)
• Open drainage and lavage in the OR

Disposition

• All patients should be admitted with Ortho consult and continued on IV antibiotics

See Also

Arthrocentesis

Source

http://emprocedures.com/arthrocentesis/analysis.htmEmedicine