Parasites and Biliary stones

Relationship between clonorchis sinensis and biliary stones ٩٥
Relationship between clonorchis sinensis and
biliary stones
When larvae of C. sinensis reach the biliary system and mature, the
flukes provoke pathological changes, both as a result of local trauma and
of toxic irritation. The appearances vary with duration and severity of the
infestation, but they are sufficiently distinctive and characteristic to allow
a classification into four phases as follows; 1st phase, desquamation of
epithelial cells, 2nd phase, hyperplasia and desquamation of epithelial
cells, 3rd phase, hyperplasia and desquamation of epithelial cells, and
adenomatous tissue formation, and 4 th phase, marked proliferation of the
periductal connective tissue with scattered abortive acini of epithelial
cells and fibrosis of the wall of the bile duct (Min, 1984). Heavy
infestation results in obstructive jaundice and has a close relationship
with recurrent pyogenic cholangitis and cholangiocarcinoma (Lim, 1990).
Biliary infestation by Clonorchis sinensis leads to inflammation of
the biliary epithelium, enhancing mucin secretion and providing a nidus
for stone formation together with fragments of parasites and/or their eggs
(Chen et al., 1984).
Clonorchiasis is a parasitic disease of the bile ducts that occurs in
endemic areas after ingestion of the raw flesh of freshwater fish. The
echogenic foci which present in US distinguished from stones because
they were fusiform, weak in echogenicity, and floated with a change in
position. Clonorchiasis should be considered when sonography discloses
the characteristic pattern of bile duct dilatation with increased wall
echogenicity and non shadowing, discrete, echogenic foci in the
gallbladder lumen (Lim et al., 1989).