The current treatment landscape: other fungal diseases (cryptococcosis, fusariosis and mucormycosis)

Compared with major invasive mycoses such as aspergillosis and candidiasis, the antifungal stewardship management strategies of other fungal diseases have different opportunities and considerations. Cryptococcosis, fusariosis and mucormycosis are globally prevalent invasive fungal diseases (IFDs), but are not currently included in antifungal prophylaxis guidelines for immunocompromised hosts. Since the implementation of biomarkers as part of diagnostic screening strategies, the concept of pre-emptive antifungal therapy has emerged for these IFDs. Management of cryptococcosis, the most common IFD worldwide, generally utilizes a pre-emptive or therapeutic strategy that does not involve prophylaxis or empirical antifungal treatment strategies. Antifungal stewardship outcomes for cryptococcosis may vary according to the availability of local resources. Invasive fusariosis, the second-most common form of non-Aspergillus mould infection among haematological malignancy patients, can be managed with pre-emptive (or diagnostic-driven) approaches based on the monitoring of serum galactomannan (GM) antigen in increased-risk populations. The success of antimicrobial stewardship programmes in decreasing the burden of invasive fusariosis in selected patient populations depends on the development and implementation of rapid diagnostic strategies for early and appropriate administration of therapy. Mucormycosis may emerge as a breakthrough IFD in haematology or solid organ transplant recipients receiving antifungals that lack activity against Mucorales. The concept of pre-emptive antifungal therapy has thus arisen for mucormycosis in the haematology setting because of the recent availability of circulating Mucorales DNA measurement. These examples demonstrate the challenges of implementing antifungal stewardship programmes in areas with limited resources, as well as in IFDs that are difficult to diagnose and treat.