Answer: Schistosoma sp. ova; most likely S. mansoni
As the readers pointed out, the appearance of eggs within granulomas in a perianal skin biopsy is highly suggestive of schistosomiasis, and image 4 might have the beginning of a lateral spine to support the diagnosis of S. mansoni infection. Unfortunately, the eggs tend to collapse in tissue sections and therefore it is difficult to definitively identify the characteristic spines. A stool examination is recommended to confirm the identification of these eggs. In this case, the O&P confirmed that this was S. mansoni infection.
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