Incidental detection of Wuchereria bancrofti in a Liquid-based cytology smear coexisting with ovarian serous cystadenoma and bilateral hydrosalpinx: A rare case report

Background: Lymphatic filariasis, caused predominantly by W. Bancrofti, remains a significant public health concern in several parts of India, including Bihar. Although microfilariae are commonly found in peripheral blood and lymphatic tissues, their detection in cervicovaginal cytology smears is extremely rare and is usually an incidental finding during routine cervical cancer screening. Case Presentation: A 50-year-old multiparous woman (P3L3) presented with abnormal uterine bleeding (AUB-A). Ultrasonographic evaluation showed adenomyosis with hydrosalpinx .A Liquid-Based Cytology (LBC) Pap smear revealed sheathed microfilariae and was reported as Negative for Intraepithelial lesion or malignancy (NILM) with presence of organism consistent with morphological features of W. Bancrofti. The patient subsequently underwent vaginal hysterectomy with bilateral adnexal removal, and histopathological examination revealed a right ovarian serous cystadenoma and bilateral hydrosalpinx. No adult filarial worms were identified in the surgical specimen. Conclusion: This case highlights the diagnostic value of meticulous cytological screening, particularly in filariasis-endemic regions. The incidental detection of microfilariae in an otherwise NILM smear, along with the coexistence of ovarian serous cystadenoma and bilateral hydrosalpinx, underscores the importance of maintaining a high index of suspicion for occult parasitic infections during routine cytological evaluation.