Sunday, May 31, 2020

Answer to Case 593

Answer to Parasite Case of the Week 593: Strongyloides fuelleborni

This fascinating zoonotic parasite is endemic to parts of sub-Saharan Africa and infects both human and non-human primates. It is likely under-reported, which may be due to the resemblance of its eggs to those of the hookworms. Unlike hookworm eggs which are shed in an unembryonated state, the eggs of S. fuelleborni typically contain fully-developed larvae.

Similar appearing eggs with larvae may also be seen with heavy infections with Strongyloides stercoralis; however, the eggs are seen in conjunction with larvae, and occasionally adult worms, which are not seen with S. fuelleborni cases. Here are a couple of past examples of S. stercoralis from my blog with adults, larvae and eggs:
Case 469 Question and Answer
Case 499

Idzi Potters and his colleagues suspected S. fuelleborni in this case based on the appearance of the eggs, and were later able to confirm the identity through sequencing of the 18S rRNA gene.

After leaving the specimen in the refrigerator for 5 days, Idzi was also able to observe larvae from the parasite including the following example:
You can read the whole report in his recent publication:

Thanks again to Idzi and the Institute of Tropical Medicine Antwerp for donating this case!


Sean G. Smith said...

awesome case and awesome comments. many thanks to idzi and bobbi for posting and to all for the many teaching moments... cheers! ~ s

Idzi P. said...

Thanks Sean!
I’m glad you liked it!

Unknown said...

I was catching up on recent cases and noticed that Case of the Week 593 was posted 6/1 but the Answer to Case 593 was posted the day before, 5/31. Studying is really paying off, I totally knew the answer even before I read the case!


ParasiteGal said...

Hi Harry, I do that for all of my posts, assuming that most people read the cases backwards, starting with the most recent one. Perhaps I should reverse that? thanks for writing!

Unknown said...


That was the sound of my self-assurance blowing out the window.