Management of Infectious Tenosynovitis

Diagnosis

MRI is the recommended imaging modality for establishing the diagnosis of infectious tenosynovitis and other deep soft tissue infections, along with CT scan and ultrasound studies, according to the Infectious Diseases Society of America 1
Cultures of blood and purulent material should be obtained to guide definitive therapy, as recommended by the Infectious Diseases Society of America 1

Initial empiric antibiotic coverage should be directed toward staphylococci and streptococci, with options including oxacillin or nafcillin 2g every 6h IV, or cefazolin 0.5-1g every 8h IV, as suggested by the Infectious Diseases Society of America 2
For more severe or complicated infections, broader coverage is recommended, including vancomycin 15 mg/kg every 12h IV, plus piperacillin-tazobactam, ampicillin-sulbactam, or a carbapenem, according to the Infectious Diseases Society of America 1, 2

For infections following animal or human bites, amoxicillin-clavulanate is recommended as it covers both aerobic and anaerobic bacteria, as suggested by the Infectious Diseases Society of America 1, 3
For cat bites specifically, be aware of higher prevalence of anaerobes and P. multocida, and avoid using first-generation cephalosporins, penicillinase-resistant penicillins, macrolides, and clindamycin, according to the Infectious Diseases Society of America 3

Antibiotics should be administered intravenously initially, and once the patient is clinically improved, oral antibiotics are appropriate, with a total duration of 2-3 weeks of therapy recommended for uncomplicated cases, as suggested by the Infectious Diseases Society of America 1
Repeat imaging studies should be performed in patients with persistent symptoms or bacteremia to identify undrained foci of infection, according to the Infectious Diseases Society of America 1

Prompt surgical consultation is recommended for aggressive infections associated with signs of systemic toxicity, as suggested by the Infectious Diseases Society of America 2

Patients should be monitored for clinical improvement and resolution of symptoms, according to the Infectious Diseases Society of America 1

Tissue biopsy provides the most sensitive specimen for culture, particularly when mycobacterial infection is suspected, according to the American Thoracic Society 4, 5

For animal or human bite-associated tenosynovitis, the Infectious Diseases Society of America recommends amoxicillin-clavulanate to cover both aerobic and anaerobic oral flora, with a duration of 4 weeks for septic arthritis and 6 weeks for osteomyelitis 6
For mycobacterial tenosynovitis, the American Thoracic Society suggests macrolide (clarithromycin or azithromycin) plus ethambutol based on susceptibility testing, with ciprofloxacin and sulfonamides showing good activity against M. terrae complex 7, 8, 9

Prompt surgical debridement and drainage prevent tendon necrosis and functional loss, according to the American College of Cardiology, with infected wounds not being closed primarily 6, 10
Half of mycobacterial tenosynovitis cases require extensive debridement, surgical intervention, or amputation despite medical therapy, as reported by the American Thoracic Society 7, 8

Elevate the affected extremity to accelerate healing, especially if swollen, as recommended by the Infectious Diseases Society of America 6
Ensure tetanus prophylaxis is current and consider rabies prophylaxis for feral/wild animal bites in endemic areas, according to the Infectious Diseases Society of America 6

Foot infections in patients with peripheral artery disease (PAD) carry nearly 3-fold higher amputation risk when infection and PAD coexist, requiring immediate interdisciplinary care team referral, vascular imaging, and expeditious revascularization, as stated by the American College of Cardiology 10

Outpatients should be reassessed within 24 hours by phone or office visit, and if infection progresses despite appropriate antimicrobial and surgical therapy, hospitalization is required, according to the Infectious Diseases Society of America 6