Monday, April 9, 2018

Case of the Week 489

Happy Unicorn Day! (yes, there really is such a thing).
This was seen in a trichrome-stained stool specimen. It measures approximately 19 micrometers in diameter, not including the 'horn'.
These were also seen in this specimen:

Identification? Images are courtesy of Emily Fernholz, MLS(ASCP).


Rasta Bob said...

E. coli (>4 nuclei) - with a giant karyosome?

Blaine Mathison said...

The cysts are unmistakably Entamoeba coli. The troph is atypical but not out of the realm of possibility. I never put a lot of weight into the karyosome when identifying Entamoeba species, but rather I tend to look more to the pattern of the peripheral chromatin. That being said, in the absence of cysts, this troph by itself would be impossible to identify to the species level and would be more suggestive of E. polecki over E. coli. Of course, who would call an Entamoeba based on only one troph over 10 micrometers? No one, I'd hope...(well unless there were obvious ingested erythrocytes ;-)

Anonymous said...

A classic case of E. coli trophozoite and cysts. For sure this case is a textbook, however the organism especially the cysts stage does not always render the nuclei on the same focal plane, a challenge when photographing with the oil immersion lens. Congratulations and thanks to Emily for the beautiful pictures.
Florida Fan

Lyne said...

Entamoeba coli cysts and troph

William Sears said...

Entamoeba Coli given size and greater than 4 nuclei clearly visible in cyst.

Idzi P. said...

I agree with E. coli for the last two pictures.
The first picture shows what seems to me a Iodamoeba butschlii trophozoite or maybe Endolimax nana trophozoite (nice ring of peripheral chromatine with very large karyosome). The size pushes me towards Iodamoeba though... nice pictures! Happy unicorn day!

Anonymous said...

1) trofozoita di Jodamoeba butschlii
2) e 3) Cisti di Entamoeba coli

Carlo Alberto

Bobbi Pritt said...

Based on the diverse responses I've received so far, I've added a few more photos of the trophozoites we saw. Maybe this will make things easier (?)

Idzi P. said...

Oke... I take it back then... ;-)
Not Iodamoeba, but trophozoite of E. coli!
The second (added) picture shows the typical diffuse karyosome of Entamoeba coli.
The third picture looks like a dog’s face, no?

Atiya Kausar said...

Entamoeba coli cysts and trophozoites ...nice pictures

Anonymous said...

D'accord, ça ressemble le profil d'un chien, mais lequel ?
Quand à moi, c'est celui de Tintin.
Florida Fan

R. Cudiamat said...

The first 4 photos show varying morphology of Entamoeba coli trophozoites The dirty perikaryosomal space and the imperfect perikaryosome, the karyosome, the size are characteristics of Entamoeba coli.
The last 2 pictures are Entamoeba coli cysts having more than 4 nuclei.