Human proliferative sparganosis. A new Japanese case.

Human proliferative sparganosis is a rare parasitic disease in which the larval cestodes of unknown species proliferate in the various organs in the whole body. The authors describe a patient with innumerable parasites in the buttock and pelvic bone. The parasites were of globular or egg-like forms, up to 3 mm in diameter. Histologically, the wavy tegument, a few layers of epidermal cells, underdeveloped muscle cells, excretory channels, and calcareous corpuscles were found in the parasites. These morphologic findings confirmed the nature of maldifferentiated plerocercoid. The serologic data suggested a close relation between Sparganum proliferum and Spirometra erinacei.