Melanized fungi in human disease

Area of Science:

• Mycology
• Infectious Diseases
• Pathogen Discovery

Background:

• Melanized (dematiaceous) fungi are soil-dwelling organisms found globally, increasingly identified as pathogens.
• These fungi cause a spectrum of infections, including chromoblastomycosis, mycetoma, and phaeohyphomycosis, affecting various host defenses.
• Melanin, a pigment in these fungi, is implicated as a key virulence factor.

Purpose of the Study:

• To review the growing recognition of melanized fungi as human pathogens.
• To discuss the expanding spectrum of diseases caused by these fungi.
• To highlight diagnostic challenges and therapeutic considerations.

Main Methods:

• Review of clinical case reports and scientific literature on melanized fungi infections.
• Analysis of diagnostic approaches, including microscopy, pathology, and clinical assessment.
• Evaluation of current therapeutic strategies and in vitro antifungal activity.

Main Results:

• Melanized fungi are implicated in an increasing number of infections, including allergic diseases, localized infections, pneumonia, brain abscesses, and disseminated disease.
• In immunocompetent individuals, they are common causes of allergic fungal sinusitis and brain abscess.
• Diagnosis is challenging due to their frequent classification as contaminants; melanin is a suspected virulence factor.

Conclusions:

• Melanized fungi represent a growing group of important human pathogens with a broad clinical spectrum.
• Effective diagnosis necessitates careful pathological and clinical evaluation.
• Treatment varies by syndrome, with systemic infections often proving refractory; triazoles show consistent in vitro activity.