A Case of Invasive Rhinosinusitis Caused by Penicillium brasilianum.

Penicillium brasilianum is an environmental filamentous fungus with useful applications in biotechnology. However, human infections caused by P. brasilianum are rare and not well understood. We present the case of a woman in her sixties with poorly controlled diabetes mellitus who was diagnosed with invasive fungal rhinosinusitis (IFRS) and orbital apex syndrome. She underwent endoscopic sinus surgery and received treatment with liposomal amphotericin B. Notably, β-tubulin gene sequencing identified the filamentous fungus as P. brasilianum, and long-term itraconazole administration suppressed IFRS flares. Our findings underscore the need for increased awareness and understanding of rare fungal pathogens in clinical practice.