Saturday, July 6, 2024

Answer to Case 751

 Answer to the Parasite Case of the Week 751: Anisakis species. 

Thanks to all who provided comments on this case! Idzi kicked us off with his comment: "The Y-shaped lateral chords tell me that this is patient has eaten raw (or undercooked) fish! 😉". Florida Fan then elaborated, "The cross sections tell us that this is a nematode. From online publications and Idzi's comment, the very tall musculature and Y-shaped lateral chords favor a diagnosis of anisakiasis."

Here is an annotated image showing some of the key features:

Note the eosinophilic tissue response surrounding the worm. 
Thanks again to Dr. Jones for donating this classic example of anisakiasis in tissue. 



2 comments:

Anonymous said...

Is this enough to differentiate from other Anisakid genera such as Pseudoterranova and Contracaecum ?

ParasiteGal said...

Great question. Yes, the Y-shaped lateral chords on a narrow base allow us to identify this as an Anisakis species. The lateral chords of other 2 genera have a broader base and are described as 'butterfly-like'.