Monday, November 12, 2018

Case of the Week 518

This week's case is a bit of a puzzle for you to put together. The following object was seen in a urine sediment. It was initially moving, but very quickly died. It measures approximately 130 micrometers in length.
Wet prep, 10x objective
 Wet prep, 40x objective


Identification? Images are by one of our Clinical Microbiology fellows, Dr. Sarah Jung.


Monday, November 5, 2018

Case of the Week 517

Case of the Week 513
This week features our monthly case from Idzi Potters and the Institute of Tropical Medicine, Antwerp.

A 45-year-old female patient, suspected of having an infection with Strongyloides stercoralis, provided a stool specimen for Baermann concentration. The following structure was found, measuring about 300 ┬Ám in extended state. Diagnosis please.





Sunday, November 4, 2018

Answer to Case 517

Answer: rotifer

Wow, great comments on this case!  The Old One mentioned that this is a bdelloid rotifer. He comments "In this year of the women, it should be noted that bdelloid rotifers are all female. Able to be successful for millennia while maintaining genetic diversity by taking DNA from other creatures." Fascinating! According to the Encyclopaedia Britannica, "Rotifer, also called wheel animalcule, any of the approximately 2,000 species of microscopic, aquatic invertebrates that constitute the phylum Rotifera. Rotifers are so named because the circular arrangement of moving cilia (tiny hairlike structures) at the front end resembles a rotating wheel." 

There is no clinical significance to this finding. Rotifers are found in environmental water sources, so it is likely that the organism entered the specimen through the collection process - possibly from toilet water contaminated with untreated water.

We've seen a rotifer before on this blog - in Case of the Week 304. Check out the photos from the case contributor, Ahrong Kim in South Korea - they're beautiful!

Friday, November 2, 2018

Halloween Parasite #5

HERE is Halloween Parasite #5, the last in my series of creepy dreadful wonderful parasites for the Halloween season. These pieces are written for the general public, including children, and aim to interest more people in the fascinating world of parasitology.

Thursday, November 1, 2018

Halloween Parasite #4

Happy Halloween Week everyone! As you all know, parasites can be creepy dreadful, but also fascinating, and sometimes even helpful. As a special Halloween treat, I'll be highlighting 5 different parasites on the Mayo Clinic News Network - 1 each day. HERE is parasite #4 - "worms in love" These are written as educational pieces for the general public. Feel free to use the text and images for your own educational purposes.



Wednesday, October 31, 2018

Halloween Parasite #3

Happy Halloween Week everyone! As you all know, parasites can be creepy dreadful, but also fascinating, and sometimes even helpful. As a special Halloween treat, I'll be highlighting 5 different parasites on the Mayo Clinic News Network - 1 each day. HERE is parasite #3 - . These are written as educational pieces for the general public. Feel free to use the text and images for your own educational purposes.

Tuesday, October 30, 2018

Halloween Case #2

Happy Halloween Week everyone! As you all know, parasites can be creepy dreadful, but also fascinating, and sometimes even helpful. As a special Halloween treat, I'll be highlighting 5 different parasites on the Mayo Clinic News Network - 1 each day. HERE is parasite #2 - scalp explorers. These are written as educational pieces for the general public. Feel free to use the text and images for your own educational purposes.

Monday, October 29, 2018

Halloween Case #1

Happy Halloween Week everyone! As you all know, parasites can be creepy dreadful, but also fascinating, and sometimes even helpful. As a special Halloween treat, I'll be highlighting 5 different parasites on the Mayo Clinic News Network HERE - 1 each day.

I unfortunately will not be having a Halloween party this year since I am at the annual meeting of the American Society of Tropical Medicine and Hygiene in New Orleans. Therefore I won't have any costume photos from my party, but I promise to post photos later if I see any particularly parasite-like costumes on Bourbon street!

Monday, October 22, 2018

Case of the Week 516

This week's case was generously donated by Dr. Josette McMichael, an American dermatologist currently working in east Africa. The patient is an elderly woman who presented with a 2-week history of 10 pruritic burning nodules involving her left upper arm, face, breast, chest, trunk, and legs. Here is a video of one of the lesions:

This object was removed and placed in a sterile container without preservative:
It was still quite lively!

Approximately 1 week later, it was sent to my lab for identification. Even though it had darkened significantly, the diagnostic features were still apparent. Here is the posterior end:
Identification?



Sunday, October 21, 2018

Answer to Case 516

Answer: Cordylobia anthropophaga, the mango or tumbu fly.

As Florida Fan nicely outlined, there are several initial features that lead us to the identification:

1. The patient is from Africa, where we can find the tumbu fly.
2. The size of the larva is about one third or one fourth the diameter of the cup, roughly 13-15 mm in length, compatible to that of this fly's larva size.
3. There is no discernible peritreme nor ecdysial scar.
4. The spiracles open through sinuous slits.

The following image shows the posterior spiracles, with the sinuous slits (arrow head). Note that the peritreme is not easily discernible (arrow).
Blaine and I covered this classic causes of myiasis in our CAP Arthropod Benchtop Reference Guide. The key morphologic features are its robust form, cuticular spines on all body segments (not clearly shown here), spiracular plat with a very weak peritreme, and sinuous slits. As Blaine pointed out, you can differentiate C. anthropophaga from the similar-appearing species, C. rodhaini, by its much more sinuous slits.