Metagonimus yokogawai

Metagonimus yokogawai is an intestinal Trematode.

Disease / Pathology

Metagonimus yokogawai infections are similar to that of Heterophyes Heterophyes and symptoms are dependent on the worm burden. Complications can occur when the eggs infiltrate the intestinal capillaries and lymphatics. When this occurs the eggs can be transported to various areas of the body (brain, spinal cord, etc…) and result in emboli or granulomatous reactions that may be life threatening.

Location in the Host

Metagonimus yokogawai adults are attached to the walls of the small intestine.

Geographic Distribution

Metagonimus yokogawai is found in the Far East, Soviet Union, Israel, Korea, Balkans, China Japan, and Spain. The reservoir for the parasite are fish-eating mammals.

Life Cycle

Metagonimus yokogawai is transmitted from the ingestion of raw or undercooked fresh water fish.

Morphology & Diagnosis

Metagonimus yokogawai eggs can be recovered in the feces. The eggs are very similar in size and shape to Clonorchis sinensis and Heterophyes heterophyes. An examination by an experienced parasitologist must be made to distinguish the three. And even then definitive identifications must include clinical findings, and patient history. Rarely the worms can be recovered after therapy or even at autopsy where a definitive identification can also be made.