Incidental detection of filaria in fine‐needle aspirates: A cytologic study of 14 clinically unsuspected cases at different sites

Abstract

Filariasis is a major health problem in tropical countries like India. Detection of microfilariae or adult worm or egg in FNAC is very unusual despite the high incidence of this parasite in endemic zone. The aim of this study was to document the value of fine-needle aspiration cytology (FNAC) in diagnosis of filaria at all possible sites presenting as mass or swelling. Fourteen patients (nine males and five females) in the age range of 14-61 years were subjected to FNAC. FNA from swellings was done using 22-gauge needles fitted with 10 or 20 ml disposable plastic syringes. The slides were stained with May-Grunwald-Giemsa stain, Haematoxylin and Eosin (H&E) stain, and Papanicolaou (Pap) stain. In total, 14 cases of filariasis were detected, which included subcutaneous swellings (six cases), epididymis/spermatic cord nodules (four cases), breast lumps (two cases), lymph nodes (one case), and thyroid swelling (one case). Larvae (microfilariae), eggs, and adult worms were detected in cytological smears. Microfilaria was present in all 14 cases whereas adult worm was found in three cases only. In four cases, eggs were seen in the smears. None of the patients was microfilariaemic and significant eosinophilia (>10%) was seen seen in two patients. Filarisis should be considered as one of the differential diagnosis of swelling in endemic area. Identification of the parasite, Wuchereria bancrofti, in FNA smears and accurate diagnosis of filaria is important to employ proper treatment. Early diagnosis and treatment prevents the more severe manifestation of the disease, lymphatic filariasis.

Role of Cytology in Detection of Unsuspected Carriers of Microfilariae: A Retrospective Study in National Capital Region (NCR), India

“…The detection rate of 0.03% detected in this study is similar to the value of 0.078% in other studies conducted in Delhi/NCR, [6] while it is low as compared to studies in endemic areas. [4,[8][9][10] Among the various nematodes which can cause filariasis, Wuchereria bancrofti is responsible for 90% cases worldwide and 99.4% cases in India, while Brugia malayi accounts for the remainder. [1,2] This is corroborated by the detection of microfilariae of W. bancrofti in all the cases in this study, similar to other Indian studies.…”

“…[1,2] This is corroborated by the detection of microfilariae of W. bancrofti in all the cases in this study, similar to other Indian studies. [4][5][6][7][8][9][10][11][12][13][14][15][16] Filariasis causes a spectrum of diseases including asymptomatic amicrofilaremia, asymptomatic microfilaremia, acute lymphangitis, lymphadenitis, lymphedema, chronic lymphadenitis, elephantiasis and tropical pulmonary eosinophilia.…”

“…[3] These are the cases detected in our study, similar to other studies, where detection of microfilariae in cytological material has been incidental. [4][5][6][7][8][9][10][11][12][13][14][15][16] In our study, we have additionally retrieved the radiologic data in all cases, which was of no additional help, and was even misleading in two cases (1 thyroid, 1 breast swelling). Predominance in the third decade has been noted in other studies.…”

“…All the cases in this study showed amicrofilaremia, which is consistent with the observation that filariasis can exist without microfilaremia. [8,16] Thus, not only clinical and radiologic, but haematological parameters were also innocuous.…”

“…[1,3] Despite its high incidence, it is unusual to detect microfilaria in cytological smears. There have been reports of single or small number of cases of microfilariae in fine needle aspiration cytology (FNAC) various sites such as breast, [4][5][6][7][8][9][10][11][12][13] lymph nodes, [4,6,[8][9][10][11][12][13][14][15] scrotum, [6,8,9,11] soft tissue swellings, [4][5][6]8,[10][11][12][13] thyroid, [6][7][8][10][11][12][13]15] ovary, [16] lung, [7,12] liver, [4] salivary gland, [5,7] gall bladder, [7] bone marrow, [4,…”