Wednesday, April 8, 2009

Worm!

A 5 year old child with a travel history to Asia presents with abdominal discomfort, diarrhea, an irritating nonproductive cough, and wheezing. A complete blood count with differential shows eosinophilia at 10%.

Challenge: The organism is shown above. What is it?

Image is in the public domain.

2 comments:

Craig Chen said...

Whoops - Stephanie/Rohan, you were right! My blog/I accidentally deleted your comment :( Sorry!

Craig Chen said...

Worm!

This is ascaris lumbricoides, an intestinal roundworm and the most common helminthic infection worldwide (estimated as 1.4 billion people infected, 25% of the world's population). It is most common in children 2-10, clustering in families, in areas with poor sanitation, Asia > Africa > South America. Transmission is by water or food contaminated with eggs. When ingested by humans, ova hatch in the small intestine and release larvae that penetrate the intestinal wall and migrate to the lungs. Larvae mature in the lungs, pass up the bronchi and trachea, and are swallowed. Adult worms mature in the intestines and are white or pink, tapered at both ends. The majority of infections are asymptomatic. Pneumonitis is known as Loffler's syndrome. Other presentations include pneumonitis (Loeffler's syndrome), intestinal obstruction at the ileocecal valve (and vomiting up worms is possible), and hepatobiliary and pancreatic symptoms.

Sources: UpToDate; Wikipedia.