- Roundworm – commonest worm to infect humans.
- Rarely presents with obstructive jaundice. Can be due to migration of worm into biliary tree or worm traversing the ampulla. Associated with recurrent pyogenic cholangitis.
- USS sometimes sees long linear filling defect within biliary tree.
- ERCP – may identify, with endoscopic extraction possible.
- Medical treatment with anthelmintics mebendazole or albendazole – often curative.
- Late complication of papillary stenosis – can be treated with sphincterotomy.