Sunday, March 22, 2015

Case of the Week 342

A 50-year old man presented with peritonitis and an acute abdomen. Emergent surgery revealed a perforation of his small intestine. Further history revealed that he had recently traveled to Costa rica.

The following are H&E stained sections of his small intestine showing unexpected structures in a blood vessel with extensive surrounding eosinophilic inflammation.

20x total magnification

40x total magnification
 200x magnification


 Around the worm were numerous eosinophils and granulomas containing foreign objects.  Here is one such granuloma.

Identification?

6 comments:

aubreynoelle said...

Anisakis simplex?

Malassezia said...

Looks like Angiostrongylus costaricensis! Lovely case.

Nermin Sakru said...

Dear bobbi,
female Angiostrongylus costaricensis

John Beach said...

Bobbi,
The previously expressed opinions "Angiostrongylus costaricensis" gave me an idea. The definitive hosts for that nematode are humans and rodents. Inside the granulomas in slide 3, the purple-stained blobs are about the right size for T. gondii (also problematic for rodents and humans.) In another type of tissue, http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3237564/, T. gondii cysts sizes were found to be between 10 and 70 ┬Ám, and 13% of cysts were in pairs.
Is this a nested-doll scenario? (protist within nematode that invades person).
Also curious if vacationing patient ate anything that could be relevant to a mollusc that is a viable intermediate host for the nematode.
Please forgive my speculation if it is way off base. I am untrained, but ever striving to learn.
Thanks,
John

Anonymous said...

Wow, another tissue invading nematode. I'm excited to remain a learner.

Florida Fan

Anonymous said...

Angiostrongylus costaricensis!

Note the multinucleated intestine of the nematode, the location of the parasite, and the patient travel history to Costa Rica.