Is a rare yeast infection at the surgical site after removal of a prosthetic hip significant or can it be ignored?

Management of Rare Yeast in Surgical Site Infection After Prosthetic Hip Removal

A rare yeast infection at a surgical site after prosthetic hip removal should be considered clinically significant and requires appropriate antifungal treatment and surgical intervention. 1

Diagnostic Considerations

When a rare yeast is isolated from a surgical site after prosthetic hip removal, several factors must be evaluated:

• The presence of a sinus tract communicating with the prosthesis site is definitive evidence of infection 1
• Purulence at the surgical site without another known etiology is definitive evidence of infection 1
• Two or more intraoperative cultures yielding the same organism constitutes definitive evidence of infection 1
• Even a single culture yielding yeast should be considered significant, especially in the context of a prosthetic joint 1

Treatment Algorithm

Surgical Management

1. Complete removal of all prosthetic material is recommended 1

   • Two-stage exchange is the preferred approach for fungal prosthetic joint infections
   • The first stage involves removal of all infected material
   • Placement of an antifungal-loaded cement spacer is beneficial 2

2. Obtain multiple tissue samples during surgical debridement 1

   • At least 3 and optimally 5-6 periprosthetic tissue samples should be collected
   • Submit samples for both aerobic and anaerobic cultures
   • Consider specific fungal cultures if yeast is suspected

Antifungal Therapy

For Candida infections of prosthetic joints, the following regimen is recommended:

1. Initial therapy 1:

   • Fluconazole 400 mg (6 mg/kg) daily for 6 weeks, OR
   • An echinocandin (caspofungin 50-70 mg daily, micafungin 100 mg daily, or anidulafungin 100 mg daily) for 2 weeks followed by fluconazole 400 mg daily for at least 4 weeks

2. Alternative therapy 1:

   • Lipid formulation amphotericin B, 3-5 mg/kg daily for 2 weeks, followed by fluconazole 400 mg daily for at least 4 weeks

3. Duration of therapy 3, 4:

   • Minimum 6 weeks of antifungal therapy
   • Many experts recommend 6 months of total antifungal therapy for fungal prosthetic joint infections

Reimplantation Considerations

If reimplantation of a new prosthesis is planned:

1. Timing of reimplantation 1, 4:

   • Delay reimplantation for at least 3-6 months after removal of infected prosthesis
   • Ensure complete resolution of infection before reimplantation
   • Consider antifungal-impregnated cement during reimplantation 2

2. Post-reimplantation therapy 1:

   • Continue antifungal therapy for at least 6 weeks after reimplantation
   • If the prosthetic device cannot be removed, chronic suppression with fluconazole 400 mg daily is recommended if the isolate is susceptible

Clinical Pearls and Pitfalls

• Do not dismiss rare yeast isolates as contaminants in the setting of prosthetic joint surgery 5, 3
• Fungal prosthetic infections often have subtle presentations and may be missed if not specifically considered 4
• Patients may not have traditional risk factors for fungal infections 5, 4
• Bacterial co-infection is common (55% of cases) and should be treated appropriately 3
• The success rate for treatment of Candida prosthetic joint infections is approximately 73% with appropriate management 3
• Inadequate surgical debridement is a major cause of treatment failure 1
• Antifungal susceptibility testing should guide therapy when available 1

Monitoring

• Regular follow-up with inflammatory markers (ESR, CRP) to assess treatment response 1
• Clinical monitoring for signs of persistent or recurrent infection
• Monitor for antifungal drug toxicity with appropriate laboratory testing

Fungal prosthetic joint infections are rare but serious complications with significant morbidity. Early recognition, aggressive surgical debridement, and appropriate antifungal therapy are essential for successful outcomes.