C D
Figure 3. Histopathologic examination of the skin biopsy is depicted below:
(A) At low magnification, the slide reveals a light grain surrounded by a mixture of inflammatory cells, including multinucleated giant cells and histiocytes (H&E, 40x original magnification).
(B) Zooming in, at high magnification, the light grain shows the presence of filamentous organisms surrounded mainly by neutrophils, epithelioid histiocytes, and some lymphocytes (H&E, 100x original magnification).
(C) In this plane, the light grains are predominantly surrounded by neutrophils (H&E, 100x original magnification).
(D) Using the PAS stain, the presence of filamentous organisms can be observed within the inflammatory cell infiltrate (H&E, 100x original magnification).
According to the findings, the patient was started on treatment with Prazosin, finasteride, amoxicillin, and TMP-SMX. Fortunately, the patient has responded well to the treatment, and the disease is currently in remission. Upon diagnosing the patient with actinomycosis, treatment with intramuscular ceftriaxone was initiated, but unfortunately, it proved ineffective, and the lesion continued to spread. Finally, the patient was referred to our clinic in 2021 with suppurative, granulomatous lesions, and abscesses. A biopsy was obtained to assess the lesion, and the histopathologic evaluation, including GMS and PAS stains, revealed bacterial aggregates forming granules with a central basophilic filamentous appearance. The GMS stain highlighted the filamentous bacteria, while the PAS stain showed no evidence of fungal organisms. Based on these histopathologic findings, mycetoma and eumycetoma were considered, and a culture was performed to detect the microbial organism, which confirmed the diagnosis of actinomycosis.
To further evaluate the extent of the lesion, a simple radiograph of the palmar bones was obtained, which indicated their involvement. Subsequently, the patient underwent an MRI scan for a more detailed assessment.