When to Stop Antifungal Medication(s)

Invasive fungal infections (IFI) can be challenging to diagnose. In some cases, however, the biggest challenge is treatment. More specifically, how to monitor treatment and when to discontinue antifungal drug(s) is most difficult. Biomarkers (fungal antigens and antibodies) are useful for treatment monitoring. MVD recommends a multi-modal approach to treatment monitoring that includes clinical signs, physical examination, imaging studies and repeat biomarker testing. Below is a table for each common IFI – systemic aspergillosis, blastomycosis, coccidioidomycosis (Valley Fever), cryptococcosis, and histoplasmosis (Tables 4-8). In addition, a common fungal-like oomycosis, pythiosis, is included. Beforehand, there is a brief review of treatment recommendations (Tables 1 & 2) and diagnostic performance of common fungal biomarker tests (Table 3). It is important to check itraconazole blood levels (MVista Itra Bioassay, test code 312) after 3 weeks of treatment ideally within 4-hours of the next dose (near-trough level).

 

 

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