Tuesday, January 27, 2009

Case of the Week 55

The following object was removed from the common bile duct during endoscopy. It is approximately 20 mm in length. Identification?

Monday, January 26, 2009

Answer to Case 55

Clonorchis sinensis (a.k.a. Oriental liver fluke) adult fluke.
Congratulations to everyone who wrote in with the correct answer!

The keys to identification of this fluke is its small size (10-25 mm long), characteristic gut bifurcation (arrows), and identification of 30 um eggs within the uterus (arrow head).

In this location, you would also want to exclude Fasciola hepatica. This fluke is larger than Clonorchis (30 mm long), has a much more complex gut branching system, and has much larger eggs.

Monday, January 19, 2009

Case of the week 54

Live from New York!



Answer to Case 54

Answer: Cimex lectularis, the common bedbug.
Seen in this movie is an adult, several nymphs, and a single egg (bottom left corner).
Congratulations to Chris who got this one right away!

Monday, January 12, 2009

Case of the Week 53

Shown is an iron-hematoxylin stain of a concentrated fecal preparation. What are the organisms shown and what is the significance of finding them?

Answer to Case 53

Answer: Iodamoeba butschlii
The key to identification of this ameba is the presence of the large dark nuclear karysome and the characteristic cytoplasmic vacuole.

Although this ameba is non-pathogenic in humans, its presence indicates that the patient has been exposed to fecally contaminated food or water. Therefore, a parasitic cause should not be exluded if it fits with the clinical presentation, and additional stool samples should be obtained for examination.

Monday, January 5, 2009

Case of the Week 52

Brain biopsy from an adult male with mental status changes. The 2 images are from the same microscopic field at different planes of focus, to demonstrate the range of findings. Identification? (CLICK ON IMAGES TO ENLARGE)

Sunday, January 4, 2009

Answer to Case 52

Answer: Toxoplasma gondii cyst and free tachyzoites. Congratulations to Alasdair, Kathryn, and the path resident who had the answer to this case! Notice the free tachyzoites that become clear as you focus up and down (arrow). One has a classic arc or 'banana' shape, diagnostic for this organism. CLICK ON IMAGE TO ENLARGE.