Hydatid cysts are typically spherical in shape and have the ability to achieve rather large sizes. The insides of the cysts are filled with fluid, brood capsules, daughter cysts, and protoscolices that have the capability to grow into adult worms if consumed by a definitive host. If a cyst is ruptured, which may occur through a sharp blow or during surgery, each protoscolex released may form a new cyst. Also, the fluid within the hydatids is highly allergenic and may cause anaphylactic shock and rapid death if freed inside the body.