For this week's case, we have a worm submitted from an otherwise asymptomatic teenager. No further history was provided. What is your identification, and how would you sign this case out?
Apologies everyone for the delay in posting a case. I've been travelling a lot and just returned from South Korea. While I was there, I was offered the following dish consisting of raw crab. If I had chosen to eat it (which I didn't), which parasites could I have acquired?
Answer to the Parasite Case of the Week 802: No significant parasite risk.
But wait, you may say, what about paragonimiasis???
As noted by Anatoly, Kim Tae Yun, and others, these are marine crabs rather than fresh water - an important distinction! Eating undercooked freshwater or estuarine (brackish) crabs could indeed lead to paragonimiasis, and this was historically an endemic infection in Korea. However, the risk from eating undercooked marine crabs is relatively low. According to Kim Tae Yun, "Most Korean people enjoy the food so called GEJANG (crab soaked in soy sauce)...And the GEJANG in the photo looks very delicious."
What do you think?
Anisakiasis and gnathostomiasis are hypothetical risks from eating freshwater crabs as well, but highly unlikely as crabs are not the typical hosts for the associated parasites.
I must admit that I chose not to eat this dish for two reasons: first, I was uncertain about the type of crab offered, and second, I'm not a huge fan of raw seafood. However, the food I did eat, including a crab hotpot and kimchi pancake, were absolutely delicious.
Thank you all for sharing your own experiences.
This week's case was an interesting finding from microscopic examination of skin scrapings. What is your diagnosis? And what forms are you seeing?
Answer to the Parasite Case of the Week 801: Sarcoptes scabei, adult and juvenile mites, eggs, and feces (scybala).
Florida Fan so nicely described the findings here as follows: "Boy, this should give the host quite an itch. We find the feces or scybala, the egg, the premature or developing stage before eclosion and finally the mother mite itself. Sarcoptes scabiei and its family members not only infest humans as itch mites but also infest other warm blooded animals as mange as well. Hopefully the Easter bunnies are spared from its cuniculi species."
Here is a closer view of two eggs (arrows) and numerous fecal pellets (the small, oval, granular structures):
Welcome to our 800th case! Given the occasion, I thought we deserved something spectacular, and these images from Heather Morris definitely fit the bill. These worms measure ~1 cm long. What is your diagnosis?
Answer to the Parasite Case of the Week 800: Enterobius vermicularis (pinworm), numerous adult females seen, with eggs in the background.
There was a lot of great discussion in this case! Florida Fan noted the lateral alae, which are one of the characteristic features of this worm. They are most prominent as cephalic inflations, but they continue along the length of the worm. Other classic features include the pin-shaped tail of the female worms, size, and location. We can't make out the eggs in these images, but Florida Fan noted that they would be flat on one side, and curved on the other (i.e., planoconvex).
Thank you for celebrating the 800th Case with me!
This week's case was donated by Drs. Jacob Rattin and Akeesha Shah. The patient is an elderly male with a history of bladder cancer, status post cystectomy, who was undergoing screening urine cytology. The specimen was collected from a urostomy bag from an ileal conduit. The following forms were seen on the Thin Prep specimen. They measure 50 to >120 micrometers long. What is your diagnosis?
Answer to Parasite Case of the Week 799: Not a parasite; plant material consistent with guar gum.
Guar gum (a.k.a. guaran) is a galactomannan polysaccharide extracted from guar beans. It has thickening and stabilizing properties that are useful for food, feed, and industrial applications. In medicine, it is often used as an adhesive to keep ostomy bags attached to the skin. This is how it likely got into the specimen from this patient.
Some readers queried if this plant material could have originated from the intestinal tract, given that the patient has an ileal conduit. However, in looking into the way an ileal conduit is created, we can see that it is disconnected from the GI tract and therefore would not contain food material.
For fun, I decided to investigate the microscopic appearance of guar gum using common parasitology stains. Below are my results using a simple wet prep, modified trichrome (Ecostain) stain, and Giemsa stain. Note that it is birefringent with polarized light, as is most plant material.
This interesting finding has been reported before by Nomani et al. Thanks again to Drs. Rattin and Shah for donating this interesting case!
It's the first Monday of the month and time for our case from the Institute of Tropical Medicine in Antwerp! This case is donated by Idzi Potters, as well as Ms. Loranne Lambregts, a new ITM friend and very promising parasitologist!
The following objects were recovered from a patient's scalp. They measure about 2-4 mm and are very motile. What is your identification?
