Cytological diagnosis of microfilariae in clinically unsuspected cases: A retrospective review of 12 cases

Abstract

Background Filariasis is a major health problem in India. Despite the high prevalence, microfilariae are rarely found in cytology smears. Most of the cases are incidentally found, solely or in association with other pathologies. Aims and Objectives This study was undertaken to analyse the prevalence and cytological findings of cases of incidentally found microfilariae in cytology smears (fine needle aspiration cytology [FNAC]/exfoliative cytology) from different parts of the body. Materials and Methods This was a retrospective study over 3 years, in which cases of microfilariae in aspirates from swelling of different locations, body fluids, and pap smears were reviewed, and the clinicopathological data analysed. Results and Analysis Out of 11 530 cases of FNAC, 8700 cases of fluid cytology, and 9000 of conventional cervicovaginal smears, 12 cases (0.04%) of incidental findings of microfilariae were documented in cytology smears. The cases were diagnosed from lymph node (one case), hand (one case), scrotal area (one case), axilla (one case), breast (one case), subcutaneous tissue (three cases), urine (three cases), and Pap smear (one case). We found eosinophilia in one case (8.3%) of filarial lesions. We found two cases of incidental findings of microfilariae in association with malignant lesions. Conclusion Cytology smear examination can play an important role in diagnosing occult filariasis in clinically unsuspected cases in association with other pathologies.

Incidental Finding of Microfilaria in Lymph Node Cytology: A Case Report

“…However, incidental detection of fine-needle aspiration cytology smears has been reported [8,9]. In cases of elephantiasis, occult filariasis, lymphangitis, and early stages of allergic presentations, microfilariae may not be seen on peripheral blood film examination [2,10].…”

Microfilaria in cervicovaginal Pap smears: A common parasite hiding in an unusual site: Short series of four cases with literature review

“…In tropical countries like India, filariasis is prevalent and causes serious health concerns. 3 The two most frequent species causing filariasis in India are W. bancrofti and B. malayi. 8 The lymphatics are most commonly affected by the adult worm of filariae while their offspring, the microfilariae, release and circulate in the peripheral blood.…”

“…1,3 Traditionally, eosinophilia and microfilaremia seen in peripheral blood smears, together with suggestive clinical features, used to diagnose. 3,4 Although many people are affected, it is uncommon to find microfilariae in routine cytology smears. 5 Majority of the prior literature revealed an incidental diagnosis of microfilaria in cytology smear from various sites, including the breast, thyroid, bone marrow, soft tissue, epididymis, salivary gland, ovarian cyst, lymph nodes, pleural fluids, pericardial fluids, and cervicovaginal smear.…”

“…5 Majority of the prior literature revealed an incidental diagnosis of microfilaria in cytology smear from various sites, including the breast, thyroid, bone marrow, soft tissue, epididymis, salivary gland, ovarian cyst, lymph nodes, pleural fluids, pericardial fluids, and cervicovaginal smear. 3,5,6 A few cases have been described in the literature where microfilariae were found in cervicovaginal smears. 7 Herein, we present four cases where microfilaria was seen as an incidental finding during routine conventional cervicovaginal smears with Papanicolaou stain (Pap smear) in asymptomatic women.…”

Breast filariasis presenting fibroadenoma like nodules: a rare diagnosis

“…The conventional mode of diagnosis of lariasis is by demonstration of micro laria in peripheral blood smear. Despite the high incidence, it is infrequent to nd micro lariae on FNAC smears and body uids (Gupta 2021). There are only a few reports in the literature with signi cant numbers of breast lariasis cases diagnosis of breast lariasis with broadenoma-like lesions.…”