Diagnostic Histopathology

Abstract

Diagnosis of mycoses using microscopy has the advantage of rapidity and often confers the advantage of showing that the fungus is invading tissue, not colonizing bronchi, pulmonary cavities, paranasal sinuses or surfaces of the skin or mucous membranes. Fungal contaminants that grow on culture are often too sparse to be seen microscopically, so the problem of contamination is less with microscopy. Some fungi are difficult (e.g., mucormycosis, histoplasmosis) or impossible to grow (e.g., lobomycosis) and are best identified by microscopy. However, microscopic diagnosis depends on the skill of the observer and the fungal species. Yeasts are easier to identify on smear or histopathology than molds.