Infestation by Echinococcus granulosus is uncommon in the United States. The discovery of primary bilateral pulmonary hydatid cysts in a child of 7 years is so rare as to be a clinical curiosity.
Osler,1 in 1882, made the first collection of cases of hydatid disease in North America. Using case records, museum specimens and personal communications from the United States and Canada, he was able to find 61 cases, in 5 of which the lesions were pulmonary. In 1895, Sommer2 increased the number of recorded cases to 110. Lyon's3 series (1902) further increased the number of reported cases to 241, in 11 of which pulmonary cysts were noted. Magath4 (1921) collected 68 cases more from the literature and added 25 from the records of the Mayo Clinic, bringing the total to 334 cases. In 5 of Magath's collected cases there were cysts of the lung; thus