Question

Which one of the following parasites may cause suppurative cholangitis?

• A. Ankylostoma duodenale
• B. Ascaris lumbricoides
• C. Necator americanus
• D. Trichuris trichiura

Hint:

Think of the large roundworm known to migrate into the bile duct.

Answer 1

The Correct Option is B

This question is about which worm can travel up into the bile duct and trigger an infected, pus forming cholangitis.

1. Ankylostoma duodenale: A hookworm that attaches to the small bowel wall and feeds on blood, causing anemia, it does not migrate into the biliary system.
2. Ascaris lumbricoides: A large roundworm living free in the intestinal lumen, it can wander through the ampulla of Vater into the common bile duct, block bile flow, and drag bacteria along with it, leading to suppurative cholangitis, and sometimes biliary colic or acute pancreatitis.
3. Necator americanus: The second common hookworm species, again a blood feeder attached to the gut wall, with no tendency to enter the bile ducts.
4. Trichuris trichiura: The whipworm stays anchored in the large intestine, mainly the cecum, and is not linked with biliary tract disease.

Only Ascaris lumbricoides has the size and the free moving habit in the gut lumen needed to enter the biliary tree and cause suppurative cholangitis.

Let's summarize:

• Ascaris worms can migrate through the ampulla of Vater into the bile duct.
• Hookworms and whipworm stay fixed to the gut wall or lumen and do not cause biliary disease.

So the parasite that may cause suppurative cholangitis is Ascaris lumbricoides.