Microfilariae of Wucheria bancrofti in bone marrow.

Abstract

We report an incidental fi nding of microfi lariae in the bone marrow aspirate of a patient who was under investigation of back pain with destruction of fi rst lumbar vertebrae. Filaria-sis is a major health problem in tropical countries including India. Filaria is a nematode belonging to the order spirurida and superfamily fi lariorida [1]. Microfi lariae may inhabit the blood vessels, lymphatic system, connective tissue and serous cavities of man and animals.A 55-year-old female, resident of village Lakhimpur, District- Budayun of Uttar Pradesh, presented with lower backache for 1 yr. On examination tenderness was found at 1st and 2nd lumbar vertebral region. Radiographs showed destruction of fi rst lumbar vertebrae. The differential diag-nosis of tuberculosis spine, metastasis to spine and multiple myeloma were put forth.To rule out these, a bone marrow aspiration was done and it was sent to pathology department for evaluation. Routine hematological investigation was within normal range. On peripheral smear the red cells were normocytic and normochromic. Platelets were adequate. No hemo-parasite or immature cells were noted in the smear. Bone marrow showed contamination with peripheral blood. The red cell precursors showed normoblastic reaction. Myeloid to erythroid ratio and myelopoisis was normal. Megakaryo-cytes also showed a normal picture. There was increase in plasma cell population. They comprised 14% of the mar-row cellularity. A small group of metastatic columnar cells (glandular origin) were seen (Fig. 1). They were supposed to be of metastatic tumor origin. One of the submitted smears showed microfi lariae of Wucheria bancrofti (Fig. 2). Based on these fi ndings the diagnosis of metastatic lesion of bone with Wucheria bancrofti microfi lariae was given.The clinical manifestations of lymphatic fi lariasis may range from asymptomatic microfi larisis to hydro-cele, lymphangitis, lymphadenitis with high grade fever(fi larial fever) and lymphatic obstruction. Our patient was clinically asymptomatic. The presence of microfi lariaehas been documented in the fi ne needle aspirationcytology of various organs other than lymphoid in past. The fi rst documentation of microfi lariae in bone marrow aspirate, available in English literature was by Pradhanet al. [2] in 1976. They showed 7 cases with peripheral