What is the treatment for fungal sinusitis?

Treatment of Fungal Sinusitis

The optimal treatment for fungal sinusitis requires a combination of surgical debridement and appropriate antifungal therapy, with the specific approach determined by the type of fungal sinusitis present. 1

Types of Fungal Sinusitis and Their Treatment

1. Invasive Fungal Sinusitis

This is the most severe form with high mortality (50-60%) and requires urgent intervention:

• Surgical Management:

  • Endoscopic surgical debridement of all necrotic sinonasal tissue is essential and improves survival (HR=0.1) 1
  • Complete removal of infected tissue with clear margins is the goal
  • Intraoperative frozen section has excellent positive predictive value (100%) but negative predictive value is only 70% 1

• Antifungal Therapy:

  • Systemic antifungals are critical and must be started immediately 1
  • For Aspergillus species: Voriconazole is superior to amphotericin B 1
  • For Mucoraceae species: Liposomal amphotericin B (60% survival rate) 1
  • In cases with orbital involvement: Consider transcutaneous retrobulbar injection of amphotericin B (1-1.5 ml at concentrations of 1-3.5 mg/ml) 1

• Additional Interventions:

  • Reduce immunosuppression when feasible 1
  • Immune stimulating interventions (associated with 70% reduction in mortality) 1
  • For diabetic patients: Consider hyperbaric oxygen therapy 1

2. Allergic Fungal Sinusitis (AFRS)

• Surgical Management:

  • Complete surgical exenteration with mucosal preservation 1

• Medical Management:

  • Systemic and topical corticosteroids 1, 2
  • Immunotherapy may be beneficial 2
  • Antifungal therapy has an unproven but potentially adjunctive role 1, 2
  • Antimicrobial agents for bacterial superinfections 2

3. Fungus Ball

• Treatment:
  • Surgical removal is indicated 1
  • Antifungal therapy is generally not required unless there's evidence of invasion

Diagnostic Considerations

Before treatment, proper diagnosis is essential:

• Imaging:

  • CT scan is first-line imaging showing extent of disease, hyperattenuation, bone erosion 3
  • MRI with contrast is optimal for suspected invasive forms and soft tissue evaluation 3
  • T2-weighted MRI signal intensity is diagnostic (very low signal similar to air indicates fungal concretions) 3

• Tissue Sampling:

  • Obtain tissue for fungal culture, histopathology, and PCR testing 3
  • Specimens should be diluted in isotonic saline 3

Prognostic Factors

Factors associated with worse survival in invasive fungal sinusitis:

• Advanced age
• Aplastic anemia (20% survival)
• Renal/hepatic failure (24% survival)
• Intracranial and cavernous sinus extension (25% survival)
• Neutropenia (29% survival)
• Hematologic malignancy (HR=3.7)
• Recent chemotherapy (HR=2.3)
• Recent bone marrow transplant (HR=2.5)
• Infection with atypical fungi (HR=3.1) 1

Important Caveats and Pitfalls

• Avoid oral corticosteroids in invasive fungal disease due to potential additive immunosuppressive effects, except when needed to reduce edema with orbital or cerebral involvement 1

• Do not delay treatment for invasive fungal sinusitis - initiation of antifungal therapy is more important than timing of surgery, but delay of surgery >30 days predicts poorer outcomes 1

• Distinguish allergic from invasive forms before treatment, as systemic antifungal medication and extensive surgical debridement are not required in allergic fungal sinusitis 4

• Monitor for nephrotoxicity and infusion reactions with conventional amphotericin B; consider liposomal formulations if these occur 5

• Recognize that long-term therapy is often needed for allergic fungal sinusitis, which is one of the most complicated conditions rhinologists must manage 2