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Description:Under a high magnification of 400X, this photomicrograph revealed some of the ultrastructural features displayed by a Clonorchis sinensis egg. C. sinensis is a trematode, or fluke, and is also known as the Chinese, or oriental liver fluke.

Clonorchis sinensis eggs are small, ranging in size from 27µm to 35µm by 11µm to 20µm. The eggs are oval shaped with a convex operculum that rests on visible "shoulders," at the smaller end of the egg. At the opposite (larger, abopercular) end, a small knob or hooklike protrusion is often visible. The miracidium is visible inside the egg.
Clinical Features:Most pathologic manifestations result from inflammation and intermittent obstruction of the biliary ducts. In the acute phase, abdominal pain, nausea, diarrhea, and eosinophilia can occur. In long-standing infections, cholangitis, cholelithiasis, pancreatitis, and cholangiocarcinoma can develop, which may be fatal.

Laboratory Diagnosis:Microscopic demonstration of eggs in the stool or in duodenal aspirate is the most practical diagnostic method. The adult fluke can also be recovered at surgery.

High Resolution: Click here for hi-resolution image (6.59 MB)
Content Providers(s):CDC/ Dr. Mae Melvin
Creation Date:1979
Photo Credit:
Links:CDC – Div. of Parasitic Diseases: Clonorchiasis
CDC Organization
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Copyright Restrictions:None - This image is in the public domain and thus free of any copyright restrictions. As a matter of courtesy we request that the content provider be credited and notified in any public or private usage of this image.