Circulating microfilariae in haematological malignancies: do they have a role in pathogenesis?

Filariasis is very common in tropical countries. It is endemic in the coastal areas of India. We report four cases of haematological malignancy where peripheral blood and bone marrow smears did not show any microfilariae but conventional cytogenetic preparations from all the four cases showed the presence of parasites. Their morphology confirmed the diagnosis of all cases as bancroftian filariasis. Therefore all types of cytogenetic preparations should be screened carefully in the endemic areas along the coastal zones of India for the presence of this parasite.