Mucor, Rhizopus, Absidia (Zygomycophyta)
Irregular, broad, nonseptate hyphae branching at wide angles.
Sporangiospores are inhaled from soil. The fungi penetrate the cribiform plate (no barriers), proliferate in blood vessel walls, progressing rapidly from sinuses into the brain tissue.
• Mucormycosis: Rhinocerebral, frontal lobe abscess; cavernous sinus thrombosis. Characterized by paranasal swelling, necrotic tissues (black necrotic eschar on face), hemorrhagic exudates from nose and eyes, mental lethargy, headache, facial pain; may have cranial nerve involvement.
• Occurs in ketoacidotic diabetic and neutropenic (leukemic) patients
Treatment: debridement of necrotic tissue and amphotericin B or isavuconazole started immediately. Fatality rate is high due to rapid growth and invasion.