Mucor and Rhizopus spp are associated with which invasive fungal infection that commonly presents with a black necrotic eschar on the face in ketoacidotic diabetic patients?

• A. Mucormycosis
• B. Candidiasis
• C. Aspergillosis
• D. Histoplasmosis

Answer: (A)

Invasive fungal infections in diabetic ketoacidosis often involve mucormycosis, an angioinvasive mold that causes rapid tissue necrosis. Mucorales, such as Mucor and Rhizopus, tend to invade blood vessels in the nasal passagessinuses, orbital area, and brain, leading to tissue death and the characteristic black necrotic eschar on the face. The fungi have broad, nonseptate hyphae that branch at wide or right angles, a pattern that helps distinguish them from other fungi (for example, Aspergillus has septate hyphae with acute-angle branching). Clinically, rhinocerebral mucormycosis follows the scenario described—diabetic ketoacidosis predisposes to it, and the black facial eschar reflects severe vascular invasion and necrosis. Prompt surgical debridement and amphotericin B are essential.