Non-Aspergillus Pulmonary Mold Infections

Non-Aspergillus molds are diverse environmental saprophytic fungi that usually cause opportunistic infections in immunocompromised hosts. The most critical non-Aspergillus mold infection (NAMI) that affects the lung is pulmonary mucormycosis (PM), caused by the Mucorlean fungi. PM usually occurs in the setting of neutropenia, immunosuppressive states, and poorly controlled diabetes mellitus and has high mortality. Recent COVID-19 infection and treatment with ibrutinib are newer risk factors for PM. Control of the underlying risk factor, surgery, and amphotericin B are the mainstays of treatment. The other NAMI include Fusarium spp., Scedosporium spp., Lomentospara spp., phaeohyphomycetes or dematacious molds, and others. The hyaline group has septate acute angle branching hyphae resembling Aspergillus spp. often requiring molecular diagnostic tools to differentiate. Also, the drug susceptibility profile is distinct from Aspergillus spp., resulting in poor outcomes to standard therapy. The management of NAMI is challenging due to the difficulty in diagnosis and limited antifungals active against the causative agents. Appropriate management requires accurate identification and knowledge of the antifungal susceptibility profile of these fungi (e.g., Lomentospora spp. is intrinsically resistant to amphotericin B). In this chapter, we review the epidemiology, diagnosis, and management (including the newer antifungal agents) of pulmonary NAMI.