What is the recommended management for infectious tenosynovitis?

Management of Infectious Tenosynovitis

Infectious tenosynovitis requires prompt surgical drainage combined with appropriate antibiotic therapy to prevent tendon necrosis and preserve function. 1

Diagnosis

• MRI is the recommended imaging modality for establishing the diagnosis of infectious tenosynovitis and other deep soft tissue infections 2
• CT scan and ultrasound studies are also useful diagnostic tools 2
• Cultures of blood and purulent material should be obtained to guide definitive therapy 2
• The number of Kanavel signs (pain with passive extension, fusiform swelling, tenderness along the tendon sheath, and flexed posture of the digit) and duration of symptoms can help determine management approach 3

Initial Management

Surgical Intervention

• Early drainage of purulent material should be performed to prevent tendon necrosis 2, 1
• Aggressive surgical management is particularly important in tenosynovitis compared to other soft tissue infections 1
• Patients with shorter duration of symptoms and fewer Kanavel signs may be treated successfully with antibiotics alone 3

Empiric Antibiotic Therapy

• Initial empiric antibiotic coverage should be directed toward staphylococci and streptococci 1
• For uncomplicated cases:
  • Oxacillin or nafcillin 2g every 6h IV, or
  • Cefazolin 0.5-1g every 8h IV 2
• For more severe or complicated infections, broader coverage is recommended:
  • Vancomycin 15 mg/kg every 12h IV (for MRSA coverage) plus
  • Piperacillin-tazobactam, ampicillin-sulbactam, or a carbapenem 2

Special Considerations

• For infections following animal or human bites:

  • Amoxicillin-clavulanate is recommended as it covers both aerobic and anaerobic bacteria 2
  • For cat bites specifically, be aware of higher prevalence of anaerobes (65%) and P. multocida (75%) 2
  • First-generation cephalosporins, penicillinase-resistant penicillins, macrolides, and clindamycin have poor activity against P. multocida and should be avoided 2

• For occupational exposures:

  • Consider unusual pathogens based on exposure history (e.g., Erysipelothrix rhusiopathiae in those who handle animal products) 4
  • Mycobacterial infections (including M. bovis) should be considered in cases with poor response to standard therapy 5

• For patients with underlying gout:

  • Coexisting gouty and infectious tenosynovitis can be particularly destructive and difficult to treat 6
  • Crystal analysis of synovial fluid may be necessary even when infection is suspected 6

Antibiotic Duration and Monitoring

• Antibiotics should be administered intravenously initially 2
• Once the patient is clinically improved, oral antibiotics are appropriate 2
• Total duration of 2-3 weeks of therapy is recommended for uncomplicated cases 2
• Repeat imaging studies should be performed in patients with persistent symptoms or bacteremia to identify undrained foci of infection 2

Prevention of Complications

• Complications include tendon necrosis, joint destruction, and systemic infection 1, 4
• Prompt surgical consultation is recommended for aggressive infections associated with signs of systemic toxicity 2
• For gonococcal tenosynovitis:
  • Ceftriaxone 1g IV or IM daily is the first-line treatment 7
  • After clinical improvement, switch to oral therapy (cefixime 400mg twice daily or ciprofloxacin 500mg twice daily) to complete 7 days 7
  • Patients should also receive treatment for potential concurrent chlamydial infection 7

Follow-up

• Patients should be monitored for clinical improvement and resolution of symptoms 2
• Functional assessment and rehabilitation may be necessary after the infection resolves 1
• For persistent infections, consider atypical organisms such as mycobacteria or fungi 1, 5