Monday, July 1, 2019
Case of the Week 550
Happy July everyone! Here is our first case of the month by Idzi Potters and the Institute of Tropical Medicine, Antwerp. The following objects were seen in a concentrated wet prep of a stool specimen from an international adoptee from Ethiopia. They measure approximately 60 micrometers in greatest dimension. Identification?
Decorticated ascaris?
ReplyDeleteYes
ReplyDeleteThe 4th picture pretty much confirms it
The size and morphology agrees with decorticated A. lumbricoides eggs.
ReplyDeleteFlorida Fan
Agree with decorticate fertilized A. lumbricoides eggs
ReplyDeleteAgree decorticated egg of Ascaris lumbricoides
ReplyDeleteEgg fertile of Ascaris lumbricoides.
ReplyDeleteAgree with decorticaded egg of A. Lombricoides
ReplyDeleteAscaris lumbricoides, egg fertile .
ReplyDeleteI happily agree with my comrades. I’m also delighted that this old dog learned a new trick today taking the form of a new word.
ReplyDeleteDecorticated (meaning to remove the bark, rind, or husk from).
This is in reference to one of the three layers of a nematode egg. The outer protein coat, an exogenous product of the nematode uterus. Unique to each species Often stained by the bile salts of its host (yellow, orange, to brown). Often uniquely textured during its creation. Some species have a friable protein coat, hence the decortication seen in this weeks specimen. Some have no protein coat.
Once the protein coat is removed, one can see the two remaining layers. The next layer is the chitinous true shell or chorion which varies little between nematode species.
The innermost layer or Vitalline membrane is the yolk, which often appears like crinkled cellophane, due to contained colloidal fats. Size and visibility can be species specific.
Within the vitelline one has a central mass of protoplasm (destined to be a new baby worm), which is separated from the fat layer by a space called the “Saftraum”.
These are all wonderful characteristics to help with egg identification
Old One,
ReplyDeleteIt's a pleasure reading your comments. You never stop to add a few more details, you Wonder you! I will bring it to my group's attention and am sure they will cringe.
No parasitologists don't grow old, they only flourish the world with their gray matter.
Florida Fan
Indeed, Old One! Always interesting to see what additional info you provide us with! I never cease to learn!
ReplyDeleteThank you. But to keep it real I'll share this with you. A quote from a friend who said this of me.
ReplyDeleteA parasitologist is a quaint person who sits on a stool looking at a stool.
Agree with fertilized decorticated Ascaris lumbricoides eggs.
ReplyDeleteWan Hafiz
And I agree with Old One (and his friend)
ReplyDelete;-)
Actually, the Ascaris egg has four layers. From outer to innermost: 1) mucopolysaccharide/protein uterine layer (the 'mammilated' albuminous layer), 2) lipoprotein vitelline layer, 3) chitin/protein layer, and 4) lipoprotein layer (ascaroside layer).
ReplyDeleteDecorticated eggs typically lack the outer layer but may lack any of the outer three layer.
Ascari egg
ReplyDelete