Fluorescence of fungi in superficial and deep fungal infections

Abstract

Background: Fluorescence of many fungi is noted when H&E stained sections are examined under a fluorescent microscope. In theory, this phenomenon could aid in the diagnosis of cutaneous and disseminated fungal infections without the delay associated with special stains. Seventy-six cases of superficial and deep fungal infections and 3 cases of protothecosis were studied to determine the clinical usefulness of this technique.

Results: In most cases, fluorescence was noted, but was not intense. Fluorescence of fungi did not correlate with the age of the specimen. In most cases, organisms in H&E stained sections were more easily identified with routine light microscopy than with fluorescent microscopy.

Conclusion: This report suggests that in H&E stained skin specimens, fluorescent microscopy is of little benefit in the identification of fungal organisms.

Figure 1

Aspergillosis: oraganisms clearly seen in H&E sections.

Figure 2

Aspergillosis: Fungi are less visible with fluorescence microscopy.

Figure 3

Tinea: H&E

Figure 4

Tinea: Highlighted by fluorescence

Figure 5

Fungal folliculitis: H&E

Figure 6

Fungal folliculitis: Fugi much more easily visualized with fluorescence microscopy