Monday, February 11, 2019

Case of the Week 531

This week's case was generously donated by Florida Fan. The following was noted in skin scrapings from an elderly man.


This moving object was still noted 5 days after collection!

Identification?

11 comments:

Unknown said...

Sarcoptes scabiei

Bernardino Rocha said...

Agree with Sarcoptes scabiei. Scabies mites mate on the host surface, and only the female burrow into the skin (horny layer), forming sinuous tunnels. Dispersed along the burrows are eggs, hatched larvae, and excrements. An efficient miner.

Anonymous said...

According also to Sarcoptes scabiei. An egg and scybala of the mite can be seen in photo 1, as well as an adult in photo 2 and in the video.
Nice images by the way.
Luis

William Sears said...

Scabies Sarcoptei

Idzi P. said...

First image shows mite egg and excrements.
Second image and video show Sarcoptes scabiei mite itself. VERY nice material indeed!!! Thanks for sharing these Florida Fan!!! I never saw these in real life in the lab... not yet... I will have to keep an eye open...

Sam said...

Sarcoptes scabiei

Blaine A. Mathison said...

You go to the doctor when your groin starts to itch
so he scraps some of your skin into a petri dish
and after a thorough microscopic examination
he tells you scabies is the cause of your sensation
to which you reply, 'Son of a ...'

Old One said...

You guys are always way ahead of me with your identifications. I thought I'd add a little blurb I wrote for the identification of Sarcoptes.

Sarcoptes scabei occur in a number of host species. Primarily in swine here in Minnesota but occasionally in humans. The male mites range in size from 213-285um long by 162-240 um wide and the female range from 300-504 !lm long to 230-420 um wide. Sarcoptes are round to ovoid when viewed from the back; when viewed from the side they are ventrally flattened and dorsally rounded (similar to a turtle). They possess short stumpy legs, and have no internal or external respiration apparatus (stigmata or tracheae). The ventral surface contains a number of chitinized plates called apodemes, the dorsal surface is partially covered by wide-angled, V-shaped-spines (>). The cuticular surface is sculptured into numerous parallel ridges which superficially resemble human finger prints, and the anus is at the posterior end of the mite (this is the characteristic used to differentiate Sarcoptes from Notoedres which has a dorsal anus and sometimes infests humans) The morphology of the developmental stages of Sarcoptes varies. You can, however, differentiate the adult stages from other mite species using easily recognized characteristics. The last segment (tarsus) of legs 1, 2, and 4 on males and legs 1 and 2 on females have a long, unjointed empodium or stalk with a small sucker-like pad at its end. These stalks are diagnostic for Sarcoptes.
You can see these suckered stalks in F.F. wonderful video.

Blaine, one of your best.

Kosta Y. Mumcuoglu said...

To the best of my knowledge, more and more physicians are using the dermoscope to see the scabies burrow and the female at the end of it

Colette said...

I agree that it is scabies...which was lecture this week in Entomology.

Kosta Y. Mumcuoglu said...

To the best of my knowledge the long structures at the end of the 3. and 4. pair of legs in female and the 4. pair of leg in male are hairs not spines.