DIROFILARIA or heartworm is a common parasite of dogs, cats, and other mammals. It is rarely encountered in human beings. Recently, two cases of human pulmonary dirofilariasis were reported by Harrison and Thompson.1 In their review of the literature they found only three cases up to 1965. Extrapulmonary human dirofilariasis is the more common form of human infestation by this parasite. Faust2 in 1957 reviewed the literature and collected 37 cases, most of them were found in southern Europe.
Four of the cases of human pulmonary dirofilariasis mentioned above presented as a "coin" lesion in a roentgenogram of the chest. The fifth case presented as a pulmonary infarct with pneumonitis. Because of this clinical pattern, human pulmonary dirofilariasis should be considered in the differential diagnosis of "coin" lesion of the lung. The following case is being reported to add to the small list of cases of human pulmonary