Perineal nodule due to enterobiasis: An aspiration cytologic diagnosis

Abstract

Subcutaneous swelling due to Enterobious vermicularis infection is rare. Their presence in perineal subcutaneous tissue is unusual and a clinical curiosity. A case of subcutaneous nodule in the perineum due to E. vermicularis infection diagnosed on fine-needle aspiration is described. Tissue reaction was granulomatous with neutrophils and eosinophils. Lack of familiarity with the morphology of parasites or its eggs, degeneration, and inadequate sampling may make the diagnosis difficult. This case report provides the morphologic clues to cytopathologists toward rendering a diagnosis and alerts them to the possibility of parasitic infection in unusual locations.

Enterobiasis in Ectopic Locations Mimicking Tumor-Like Lesions

“…The diagnosis is based on the histological finding. In two cases, the diagnosis was cytological, with typical eggs having been found by means of fine needle aspiration [39, 40]. Among the other granulomatous lesions which may be confused with perianal lesions from E. vermicularis are those due to tubercular nodules, leiomyomatosis nodules, and granulomas from foreign body.…”

Perianal nodule due to enterobius vermicularis: Cytomorphological spectrum on fine needle aspiration cytology with a review of literature

“…Adult worms often become degenerated due to their poor preservation in massive suppuration and therefore can become completely unrecognized/absent from the smears. [ 6 ]…”

“…Literature on cytology is sparse as majority of the EV infection cases were diagnosed on histology, with only few case reports in cytology,[ 6 9 10 ] with many mostly as incidental findings on cervicovaginal Pap smear examination. None of these cases highlights the various forms of eggs or hatching stages of larvae that can be encountered in these smears.…”

Dual cervical parasitosis in a psychiatric patient

“…Extraintestinal urogenital amoebiasis and enterobiasis have been reported earlier in the vulva, vagina, cervix, fallopian tubes, the urinary tract and the perineum 1–6 . Amoebic colonization of the cervix, although unusual, is not unheard of in India.…”