Unresolving pericarditis: suspect filariasis in the tropics.

Filariasis, a mosquito-borne disease, is wide spread in India. While laboratory diagnosis has been conventionally done by demonstrating microfilaria in peripheral blood smears, occasionally they are reported in various body fluids including pericardial fluid. We report the case of 33-year-old man with severe dyspnoea and chest pain, referred from a private nursing home with a provisional diagnosis of unresolving pericarditis. Pericardial tap revealed massive pericardial effusion with actively motile microfilariae. No microfilariae (Mf) were seen in the peripheral blood. Haemorrhagic effusion resolved completely with DEC. Though relatively uncommon, tropical diseases must always be considered in the etiological diagnosis of pericardial effusion.