Adult filarial worm in the aspirate from a breast lump mimicking fibroadenosis
A 30-year-old lady presented to the outpatient department with a painful swelling in her left breast. She had first noticed the swelling 2 weeks back and stated that the size was increasing slowly. There was no history of cyclical mastalgia. The patient was suffering from fever and had already undergone routine examination of peripheral blood. The report showed a hemoglobin level of 10.8 g/dl with a normal total leucocyte count and mild eosinophilia (differential count of eosinophil - 08%). The erythrocyte sedimentation rate (ESR) was high, the value being 80 mm in the first hour. On examination, a 2 × 2 cm swelling was seen in the upper outer quadrant of the left breast. The swelling was soft with vague margins and was mildly tender.\nFNAC was performed by a 24 G needle fitted to a 10 cc syringe and yielded a granular material admixed with a turbid fluid. The smears were stained with the May–Grunwald–Giemsa (MGG) stain and hematoxylin and eosin (H and E) stain. The cellular smears from the aspirate showed gravid adult filarial worms with a preserved outer cuticle layer. Numerous microfilariae were seen coming out from the paired uteri. The microfilariae incited a foreign body reaction in the form of multinucleated giant cells and granulomas [Figures and ]. The microfilariae were rounded anteriorly and uniformly tapering posteriorly with a clear space free of nuclei at the caudal end – thus morphologically resembling W. bancrofti. There was presence of few ductal cells of breast as well. The fluid-mixed background was dirty with a fair number of neutrophils, few eosinophils, cyst macrophages, and cellular debris. A diagnosis of filariasis of breast with granulomatous and foreign body reaction was made. A midnight blood sample taken after 2 days showed motile microfilariae on wet mount preparation. The patient was treated with amoxicillin-clavulinic acid, albendazole, and diethylcarbamazine (DEC). The swelling had disappeared when the patient came for follow-up after 2 weeks.