Monday, January 28, 2013

Case of the Week 243

The following fluid-filled objects were submitted to the parasitology lab for identification in Ecofix preservative (hence the slight green color).  The source was listed as liver, but no other history was given.  

Microscopic examination of the fluid inside of objects revealed the following:


Sunday, January 27, 2013

Answer to Case 243

Answer:  Echinococcal cysts of E. granulosus

As several viewers pointed out, daughter cysts of E. granulosus can be surgically removed and submitted intact to the laboratory, whereas the those of E. multilocularis cannot. This is because the cysts of the latter are not contained within a larger "mother" cyst like E. granulosus, but instead grow in an infiltrative pattern (much like a malignancy) and the individual daughter cysts are connected to one another by surrounding cellular stroma.  Examples of E. granulosus and E. multilocularis infection in histologic sections can be seen in Case 71

And now, a poem to go with this case from the talented Blaine Mathison:

There was a young man from the Caucasus

who one night did create such a ruckus
He was in such horrible pain
that his liver they did drain
and found the canine cestode Echinococcus

Monday, January 21, 2013

Case of the Week 242

The following object was  found in a stool specimen from a 3 year old child.  It measured approximately 5 mm in length.

The following egg was expressed:


Sunday, January 20, 2013

Answer to Case 242

Answer:  Hymenolepis nana, the dwarf tapeworm

The diagnostic features are its short length and characteristic proglottids, as well as its classic eggs with inner and outer shells. The inner shell has polar filaments emerging from it (arrows below), distinguishing it from H. diminuta, which does not.

Here is a poem for this case from Blaine Mathison, parasitologist extradordinaire:

There once was a kid from Indiana
Who with his oatmeal did like banana
But with his food he did eat
A most wonderful treat
The cestode known as H. nana

If you google "oatmeal" and "bugs," you will find multiple consumer complaints (and some nice YouTube videos) to explain the oatmeal reference!

Monday, January 14, 2013

Case of the Week 241

The following were seen in a stool specimen from a man with watery diarrhea.  The stain is a modified safranin stain.  They measure 8-10 microns in diameter.  Identification?

400x original magnification

1000x original magnification

Many thanks to Florida Fan for these beautiful images!

Sunday, January 13, 2013

Answer to Case 241

Answer:  Cyclospora cayetanensis oocysts

Many of you correctly commented that the differential includes the oocysts of both Cryptosporidium spp. and Cyclospora cayetanensis.  Both will stain with either the modified safranin stain or modified acid fast stain (the former tends to give better results, although the latter is more widely used).  Therefore, it is essential to measure the oocysts to differentiate between these 2 organisms.  The oocysts of Cryptosporidium spp. are 4-6 microns in diameter, while the oocysts of Cyclospora cayetanensis are 8-10 microns in diameter.

Monday, January 7, 2013

Case of the Week 240

The following ciliated objects were seen in a Papanicolaou-stained cytospin specimen of bronchoalveolar fluid.  The referring cytopathologist was concerned for potential parasites.  (CLICK ON IMAGES TO ENLARGE)


Sunday, January 6, 2013

Answer to Case 240

Identification:  Detached ciliary tufts from bronchial epithelial cells, also know by the fun-to-pronounce name "ciliophthoria". 

Everyone who wrote in correctly realized that these are NOT ciliated parasite in the respiratory tract - although they are a common parasite mimic.  On wet-preps of unfixed specimens, the cilia may still be beating and therefore they are definitely eye-catching!

Wednesday, January 2, 2013

Case of the Week 239

Here is a nice and straight-forward case to start off 2013!

The following objects were found in urine from a Nigerian immigrant.  The urine was first filtered through a Nucleopore filter, and then the filter was viewed microscopically.  Note the small scattered holes in the background; these are the holes of the filter. 

Special thanks to Heather A. for dontating this case!

Tuesday, January 1, 2013

Answer to Case 239

Answer:  Schistosoma hematobium ova

Note the characteristic terminal spine.  These are large eggs, measuring 110 to 170 in length!

Thank you all for the responses - they were all correct!