Primate Intestinal Trematode Parasitology

Clonorchis and Relatives

• Includes Clonorchis, Metagonimus, Heterophyes and Metorchis

• Liver and Intestinal flukes

• Difficult to speciate

• Pathology usually correlates with parasite burden

• Morphology of both eggs and adults is similar

• Size: 25-32µm

• Brownish or yellow in color

• May or may not have “shoulders” at operculum and knob on opposite end

Fasciola and Fasciolopsis

Fasciola:

• Large liver fluke

• Bile obstruction, abscesses, sclerosis and cancer

• Size: 120-180µm

• Brownish to yellowish, may be stained with bile from the liver

• Operculum may be wider than that of Fasciolopsis

Fasciolopsis:

• Intestinal fluke

• Diarrhea and GI issues

• Size: 120-180µm

• Brownish to yellowish with operculum

Paragonimus

• Lung fluke

• Adults can survive for decades

• P. westermani (Old World) and P. kellicotti (New World) are the most common

• Same clinical significance as dogs and cats

• Size: 65-120µm

• Various species are difficult to distinguish

• Light to medium yellow-brown with shoulder at operculum

Dicrocoelium

• Size: 30-40µm

• Operculated

• Bilaterally asymmetrical

• Miracidium is visible inside but may be difficult to see if egg is stained with bile

Schistosoma mansoni

• Size: 110-180µm

• Lateral spine

• Stool

Schistosoma haematobium

• Size: 110-180µm

• Terminal spine

• Urine

Schistosoma japonicum

• Size: 65-110µm

• Vestigial lateral spine

• stool