The histopathologic evaluation of the biopsy revealed the presence of
pink pale grains in the dermis. These grains consisted of
finely-branched filamentous organisms and were surrounded by mixed
inflammatory cells, including neutrophils. Additionally, a layer of
chronic inflammatory cells surrounded the organisms. The filamentous
organisms were visible and were highlighted by the PAS stain.
Furthermore, the presence of multinucleated giant cells among the
inflammatory cells was also identified in Figure 3.

Based on these histopathologic findings, a suspicion of mycetoma and
eumycetoma arose, prompting the request for a culture to detect the
microbial organism. The culture results later confirmed the diagnosis of
actinomycosis, as it was consistent with the histopathologic findings.