Phaeohyphomycosis as a rare cause of brain abscess in immunocompetent patients: Report of two cases

Background: Cerebral phaeohyphomycosis (CPHM) is an uncommon and life-threatening infection caused by a variety of dematiaceous fungi, especially rare in immunocompetent individuals. Due to its nonspecific clinical and radiological presentation, it is frequently misdiagnosed, delaying appropriate treatment and leading to poor outcomes. We aim to describe radiological and histopathological findings of patients with CPHM treated at our institution, highlighting the role of combined aggressive treatment on clinical outcomes. Case Description: We present two cases of brain phaeohyphomycosis in healthy women, aged 58 and 73 years. The first presented with hemiparesis, headache, and seizure. The second presented similarly, in addition to a decrease in level of consciousness and vomiting. Radiologically, the lesions showed ring peripheral enhancement on T1-weighted imaging, hyperperfusion in the lesion capsule, and extensive surrounding edema. Both occurred in the frontal lobe. Histopathological examination confirmed CPHM, revealing chronic granulomatous inflammation with multinucleated giant cells containing pigmented fungal hyphae. Gross total resection was performed, followed by systemic antifungal therapy. Fungal cultures were negative. One patient died. Conclusion: These cases highlight the diagnostic challenge and therapeutic significance of early recognition and aggressive management of CPHM. Surgical resection combined with systemic antifungal therapy can improve prognosis.