Ultrastructural study of Echnococcus granulosus larval forms.

The larval forms of Echinococcus granulosus were surgically removed from Turkana hydatid patients and studied on the electron microscope. It was found that the larval forms "hydatid cyst" consists of a protective laminated layer that surrounds the germinal layer. The germinal layer is made up of numerous germinal cells that transform to brood capsules within which protoscolices are formed. Protoscolices are formed from accumulations of undifferentiated germinal cells. The brood capsule wall is similar to germinal layer and they were found to contain numerous invaginated protoscolices. The invaginated protoscolices were of various sizes and they were not attached to the wall of the brood capsule. The evaginated protoscolex has two body regions, the head (scolex) and body (soma). The scolex is covered by numerous long microtriches whereas the soma is covered with few short microtriches.