Monday, July 25, 2011

Case of the Week 169

I have a challenging case for you this week!
During routine colonoscopy for colon cancer screening, endoscopists noted the following worm-like objects in the cecum:

One of these objects was removed and sent to surgical pathology where it was fixed in formalin, paraffin embedded, and sectioned for staining with hematoxylin and eosin. Unfortunately, no intact objects were sent to microbiology for identification. The portion of the object shown measures 2.5 mm. (CLICK ON IMAGES TO ENLARGE - YOU'LL WANT TO SEE THE DETAILS ON THIS ONE!)

40x original magnification

100x original magnification

200x original magnification

1000x original magnification


ladybug said...

Trichuris trichiura whipworm.

Anonymous said...

Really wierd. Looks like hooklets in high power. ?Tapeworm, but not confidently and not sure which.

Neuro_Nurse said...

Hymenolepis sp.

Lukus Roberts said...

definately cestode - can see that from the 'segmentation' - looks like the dwarf tapeworm - Hymenolepis nana. More of a nuisence parasite than dangerous except in infections of children.

adults only get to around 30-45 mm. The worm has an interesting lifecycle flexibility - it can be transmitted via a direct transmission route from person to person as well as being transmitted by fleas which can serve as intermediate hosts/vectors. As far as I am aware, this tapeworm is the only one known which does not require an obligate imediate host to develop to an infective stage for transmission.

the only thing making me go - 'errr' is that I thought the eggs were more spherical than the ones i can see here - but maybe this is after they are released from proglottids?

Kathy said...

I agree with Hymenolepsis nana. For the eggs inside the proglottids try the CDC site

MicrobeMan said...

I'll go with Hymenolepis sp. as well. To address Lukus' comment regarding the morphology of the eggs shown here, I'm wondering if these aberrations are in part, or wholly, due to fixation and/or processing of the thin sections.