{"paper_id":"751d9933-0218-4bfb-8e0f-cfe6bc35bbe2","body_text":"~ 2525 ~ \nInternational Journal of Clinical Obstetrics and Gynaecology 2026; 10(4): 2525-2528 \n \nISSN (P): 2522-6614 \nISSN (E): 2522-6622 \nIndexing: Embase \nImpact Factor (RJIF): 6.71 \n© Gynaecology Journal \nwww.gynaecologyjournal.com \n2026; 10(4): 2525-2528 \nReceived: 20-04-2026 \nAccepted: 18-05-2026 \n \nDr. Sukhmanjeet Chawla \nDepartment of Pathology, Mata \nGujri Memorial Medical College & \nLions Seva Kendra Hospital \n(MGM), Kishanganj, Bihar, India \n \nDr. Dipti Anu \nDepartment of Pathology, Mata \nGujri Memorial Medical College & \nLions Seva Kendra Hospital \n(MGM), Kishanganj, Bihar, India \n \nDr. Mala Mukherjee \nDepartment of Pathology, Mata \nGujri Memorial Medical College & \nLions Seva Kendra Hospital \n(MGM), Kishanganj, Bihar, India \n \nDr. Asitava Deb Roy \nDepartment of Pathology, Mata \nGujri Memorial Medical College & \nLions Seva Kendra Hospital \n(MGM), Kishanganj, Bihar, India \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \nCorresponding Author: \nDr. Sukhmanjeet Chawla \nDepartment of Pathology, Mata \nGujri Memorial Medical College & \nLions Seva Kendra Hospital \n(MGM), Kishanganj, Bihar, India \n \nIncidental detection of Wuchereria bancrofti in a Liquid-\nbased cytology smear coexisting with ovarian serous \ncystadenoma and bilateral hydrosalpinx: A rare case \nreport \n \nSukhmanjeet Chawla, Dipti Anu, Mala Mukherjee and Asitava Deb Roy \n \nDOI: https://www.doi.org/10.33545/gynae.2026.v10.i4ae.2789  \n \nAbstract \nBackground: Lymphatic filariasis, caused predominantly by W. Bancrofti , remains a significant public \nhealth concern in several parts of India, including Bihar. Although microfilariae are commonly found in \nperipheral blood and lymphatic tissues, their detection in cervicovaginal cytology smears is extremely rare \nand is usually an incidental finding during routine cervical cancer screening. \nCase Presentation: A 50-year-old multiparous woman (P3L3) presented with abnormal uterine bleeding \n(AUB-A). Ultrasonographic evaluation showed adenomyosis with hydrosalpinx .A Liquid-Based Cytology \n(LBC) Pap smear revealed sheathed microfilariae and was reported as Negative for Intraepithelial lesion or \nmalignancy (NILM)  with presence of organism consistent with morphological features of W. Bancrofti . \nThe patient subsequently underwent vaginal hysterectomy with bilateral adnexal remo val, and \nhistopathological examination revealed a right ovarian serous cystadenoma and bilateral hydrosalpinx. No \nadult filarial worms were identified in the surgical specimen. \nConclusion: This case highlights the diagnostic value of meticulous cytological screening, particularly in \nfilariasis-endemic regions. The incidental detection of microfilariae in an otherwise NILM smear, along \nwith the coexistence of ovarian serous cystadenoma and bilateral hydrosalpinx, underscores the importance \nof maintaining a hi gh index of suspicion for occult parasitic infections during routine cytological \nevaluation. \n \nKeywords: W. Bancrofti , Microfilaria, Liquid -Based Cytology, Pap smear, Serous cystadenoma, \nHydrosalpinx, Occult filariasis \n \nIntroduction  \nLymphatic filariasis is a mosquito -borne parasitic disease that continues to pose a major public \nhealth challenge in tropical and subtropical regions. Among the filarial parasites infecting \nhumans, W. ( Wuchereria) Bancrofti is responsible for nearly 90% of  cases worldwide. India \ncontributes substantially to the global disease burden, with several states, including Bihar, \nremaining endemic despite ongoing elimination programs  [1]. In humans, adult worms reside \nwithin lymphatic vessels, whereas microfilariae circulate in the peripheral blood, \ncharacteristically exhibiting nocturnal periodicity [2]. \nCervicovaginal cytology is routinely employed for the screening of premalignant and malignant \ncervical lesions. In addition to epithelial abnormalities, a variety of  infectious agents may \noccasionally be identified in cervical smears  [3]. However, the presence of microfilariae in \ncervicovaginal cytology is exceptionally rare because the female genital tract is not a natural \nhabitat for the parasite. Consequently, most reported cases represent incidental findings detected \nduring routine cervical screening [4]. \nThe exact mechanism responsible for the appearance of microfilariae in cervicovaginal smears \nremains uncertain. Proposed explanations include lymphatic obstruction,  rupture of superficial \nlymphatic vessels, and inflammatory damage leading to the extravasation of microfilariae into \nsurrounding tissues [5]. Although filariasis has been described in association with both benign \nand malignant gynecological conditions, its  coexistence with adnexal lesions is uncommon and \nremains a diagnostic curiosity. \nA review of the literature reveals only a limited number of case reports and small case series \ndescribing microfilariae in cervicovaginal smears. Herein, we report a rare case of incidental  \n\n\nInternational Journal of Clinical Obstetrics and Gynaecology https://www.gynaecologyjournal.com \n~ 2526 ~ \ndetection of W. Bancrofti  microfilariae in a Liquid -Based \nCytology (LBC) Pap smear from a patient presenting with \nabnormal uterine bleeding. Histopathological examination \nsubsequently revealed a right ovarian serous cystadenoma and \nbilateral hydrosalpinx, making this an unusual coexistence of \noccult filarial infection with benign adnexal pathology. \n \nCase Presentation \nA 50 -year-old multiparous woman (P3L3) presented with \nabnormal uterine bleeding (AUB -A). She had a history of three \nfull-term normal vaginal deliveries and had undergone bilateral \ntubal ligation eight years earlier. On examination, the abdomen \nwas soft and non -tender with no palpable mass. Per speculum \nexamination revealed a hypertrophied cervix with erosions \naround the external o s and whitish discharge, while per vaginal \nexamination showed a mildly bulky anteverted uterus with free \nbilateral fornices. \nLaboratory investigations revealed mild anemia (hemoglobin 9.8 \ng/dL) with eosinophilia. Peripheral blood smear showed \nnormocytic no rmochromic anemia and mild eosinophilia but \nwas negative for hemoparasites. Serological tests were non -\nreactive. Ultrasonography suggested adenomyosis with bilateral \nhydrosalpinx, more prominent on the left side. \nA Liquid -Based Cytology (LBC) Pap smear was  reported as \nnegative for intraepithelial lesion or malignancy (NILM). \nHowever, careful microscopic examination revealed a sheathed \nmicrofilaria exhibiting characteristic features of W. Bancrofti , \nincluding a slender body with smooth curves, a distinct she ath, \nand a nuclei-free tail tip (Figure 1, 2a,2b)) \nThe patient subsequently underwent vaginal hysterectomy with \nbilateral salpingo-oophorectomy. Histopathological examination \n(Figure 3a,3b)  showed chronic cervicitis, secretory \nendometrium, right ovarian serous cystadenoma, and bilateral \nhydrosalpinx. (Figure 3)  No evidence of atypia, malignancy, \nadult filarial worms, or tissue infiltration by microfilariae was \nidentified. \n \nDiscussion and Review of Literature \nLymphatic filariasis continues to be a significant public health \nconcern in many tropical and subtropical countries, including \nIndia, where W. Bancrofti  is responsible for the majority of \ncases. Although microfilariae are commonly detected  in \nperipheral blood and lymphatic channels, their presence in \ncervicovaginal cytology smears is extremely uncommon. (5) \nSince the female genital tract is not a usual site of filarial \ninfestation, identification of microfilariae in Pap smears is \ngenerally unexpected and often represents an incidental finding. \nThe occurrence of microfilariae in cervicovaginal smears was \nfirst documented by Walter et al ., [6] following which only \nsporadic case reports and small case series have appeared in the \nliterature. Most patients reported in these studies were clinically \nasymptomatic for filariasis and presented with nonspecific \ngynecological complaints such as vaginal discharge, abnormal \nuterine bleeding, pelvic pain, or postmenopausal bleeding. In the \npresent case, the patient presented with abnormal uterine \nbleeding and had no clinical features suggestive of lymphatic \nfilariasis, making the cytological finding particularly \nunexpected. \nA recent study by Kumar et al . [7] from Bihar described four \ncases of incidental detection of W. Bancrofti  in routine \ncervicovaginal Pap smears. Similar to our patient, the majority \nof these women had no clinical suspicion of filarial infection, \nand the diagnosis was established solely through cytological \nexamination. Such reports  (Table1) highlight the important role \nof routine cervical cytology in identifying occult filariasis, \nespecially in endemic regions where the disease burden remains \nhigh. Summary of previously reported cases of microfil ariae \ndetected in cervicovaginal cytology (Table 1) \n \nTable 1: Summary of Previously Reported Cases of Microfilariae \nDetected in Cervicovaginal Cytology \n \nAuthor Year Presentation Cytology Type Associated Lesion \nWalter et \nal. (6) 1983 Vaginal bleeding Conventional \nsmear None \nDhanya et \nal. (11) 2016 Vaginal discharge Pap smear None \nSingla et \nal. (4) 2020 Routine screening Pap smear None \nKumar et \nal. (7) 2022 Asymptomatic \ncases Pap smear None \nPresent \ncase 2026 Abnormal Uterine \nBleeding LBC \nSerous cystadenoma \n+ bilateral \nhydrosalpinx \n \nThe mechanism by which microfilariae reach the cervicovaginal \nregion is not completely understood. Several theories have been \nproposed, including lymphatic obstruction, rupture of lymphatic \nvessels, inflammatory damage to vascular structures, and \nincreased vascular permeability, all of which may facilitate \nmigration of microfilariae into surrounding tissues and \nexfoliated cellular material  [5, 8]. In our patient, the presence of \nchronic cervicitis and local inflammatory changes may have \ncontributed to the pa ssage of microfilariae into the \ncervicovaginal smear. \nThe increasing use of Liquid -Based Cytology (LBC) has \nimproved the quality of cervical screening by providing cleaner \nbackgrounds and better cellular preservation  [9]. Although the \nprocessing technique may cause minor morphological alterations \nin parasites, characteristic features of W. Bancrofti, including the \ndelicate sheath, smooth curves of the body, and nuclei -free tail \ntip, are usually well preserved. These features enabled accurate \nidentification of the organism in our case despite the absence of \ndetectable microfilaremia in the peripheral blood smear  [10, 11]. \nSuch findings emphasize that a negative peripheral smear does \nnot exclude occult filarial infection. \nAn additional noteworthy feature of this case is its association \nwith a right ovarian serous cystadenoma and bilateral \nhydrosalpinx. While microfilariae have occasionally been \nreported in association with both benign and malignant lesions \nof the female genital tract, coexistence with serous cysta denoma \nand bilateral hydrosalpinx is exceptionally rare. \nHistopathological examination of the surgical specimen did not \nreveal adult worms or tissue infiltration by filarial organisms, \nsuggesting that the microfilariae represented an incidental occult \ninfection rather than a direct cause of the adnexal pathology. \nThe present case underscores the importance of careful and \nsystematic evaluation of all cytological smears, including those \nreported as negative for intraepithelial lesion or malignancy \n(NILM). In regions where filariasis is endemic, awareness of \nsuch unusual presentations is essential, as incidental cytological \ndetection may provide the first clue to an otherwise clinically \nsilent infection. Early recognition facilitates timely treatment \nand may he lp prevent the long -term complications associated \nwith chronic lymphatic filariasis. \n \nConclusion \nIncidental detection of W. Bancrofti  microfilariae in Liquid -\nBased Cytology smears is an uncommon but important finding. \nThe coexistence of microfilariae with ovarian serous \n\nInternational Journal of Clinical Obstetrics and Gynaecology https://www.gynaecologyjournal.com \n~ 2527 ~ \ncystadenoma and bilateral hydrosalpinx makes the present case \nparticularly noteworthy. This report highlights the valu e of \nmeticulous cytological examination in routine cervical screening \nand reinforces the need for vigilance among cytopathologists \nworking in filariasis -endemic regions. Even in smears reported \nas NILM, careful screening may reveal unexpected findings that  \nhave significant diagnostic and clinical implications. \n \n \n \nFig 1: 40X, PAP Stain, Microfilariae-Sheathed organism, enlongated body with tapering tail \n \n \n \nFig 2a, b:  100X, PAP SMEAR, Microfilariae-body composed of a dense column of tightly packed nuclei. \n \n \n \nFig 3a, b: 40X, Right Ovary, HPE, Cyst lined by flattened to cuboidal epithelium-Serous Cystadenoma \n \n \n \n\nInternational Journal of Clinical Obstetrics and Gynaecology https://www.gynaecologyjournal.com \n~ 2528 ~ \nConflict of Interest \nNot available  \n \nFinancial Support   \nNot available \n \nReferences \n1. World Health Organization. Lymphatic filariasis. Geneva: \nWorld Health Organization; 2024. Available from: \nhttps://www.who.int/news-room/fact-\nsheets/detail/lymphatic-filariasis. Accessed June 30, 2025.  \n2. Babu S, Nutman TB. Immunopathogenesis of lymphatic \nfilarial disease. Semin Immunopathol. 2012;34(6):847 -861. \ndoi:10.1007/s00281-012-0346-4.  \n3. Ezzelarab S, El-Husseiny A, Nasreldin M, Ali R, Nabhan A; \nEarly Cervical Cancer Detection Consortium. Cervical \ncancer screening by cytology and the burden of epithelial \nabnormalities in low resource settings: a tertiary -center 42-\nyear study. BMC Womens Health. 2024;24(1):405. \ndoi:10.1186/s12905-024-03254-1.  \n4. Singla S, Singla G, Singla T, Kolte S. Incidental finding of \nmicrofilariae in cervicovaginal smears on liquid -based \ncytology: a case report of two cases with review of \nliterature. J Midlife Health. 2020;11(1):37 -39. \ndoi:10.4103/jmh.JMH_17_19.  \n5. Varghese R, Raghuveer CV, Pai MR, Bansal R. \nMicrofilariae in cytologic smears: a report of six cases. Acta \nCytol. 1996;40:299-301. doi:10.1159/000333755.  \n6. Walter A, Krishnaswami H, Cariappa A. Microfilariae of \nWuchereria bancrofti in cytologic smears. Acta Cytol. \n1983;27:432-436.  \n7. 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J Clin Diagn Res. 2016;10(4):ED08 -ED09. \ndoi:10.7860/JCDR/2016/16042.7563. \n \n \nHow to Cite This Article \nChawla S, Anu D, Mukherjee M, Roy AD.  Incidental detection of \nWuchereria bancrofti in a Liquid -based cytology smear coexisting with \novarian serous cystadenoma and bilateral hydrosalpinx : A rare case report. \nInternational Journal of Clinical Obstetrics and Gynaecology . \n2026;10(4):2525-2528.  \n \n \nCreative Commons (CC) License \nThis is an open access journal, and articles are distributed under the terms \nof the Creative Commons Attribution -Non-Commercial-Share Alike 4.0 \nInternational (CC BY -NC-SA 4.0) License, which allows others to  remix, \ntweak, and build upon the work non -commercially, as long as appropriate \ncredit is given and the new creations are licensed under the identical terms.","source_license":"CC0","license_restricted":false}