Answer to Case 672
Answer to theParasite Case of the Week 672:Enterobius vermicularis, disembodied uterus containing characteristic planoconvex (or " D-shaped " ) eggs. Note the beautiful deep pink-orange color. I have seenE. vermiculariseggs a few times on cervical Papanicolaou-stained smears, and they always looked like this.I provided the size of the eggs for those of you not used to looking at Pap smears. However, you can also estimate the size of the eggs based on the size of the background mature squamous epithelial cells, as they are about the same size. As mentioned by Florida Fan, " There must be a wandering pin worm, hopefully...
Source: Creepy Dreadful Wonderful Parasites - February 7, 2022 Category: Parasitology Source Type: blogs

Case of the Week 671
This week ' s case is by Idzi Potters and theInstitute of Tropical Medicine Antwerp. As always, he has an interesting challenge for us! the following were seen in a wet preparation of the stool concentrate. Identification? (Source: Creepy Dreadful Wonderful Parasites)
Source: Creepy Dreadful Wonderful Parasites - February 1, 2022 Category: Parasitology Source Type: blogs

Answer to Case 671
 Answer to theParasite Case of the Week 671: InfertileAscaris lumbricoideseggs, many decorticated.Decorticated eggs can pose a diagnostic challenge since they resemble eggs of other helminths such asAncylostoma duodenale, Necator americanus,Trichostrongylusspecies,Fasciola hepatica,andFasciolopsis buski,. However, they can usually be differentiated by their thicker wall, size, lack of operculum (seen with the fasciolids), and other characteristic features. (Source: Creepy Dreadful Wonderful Parasites)
Source: Creepy Dreadful Wonderful Parasites - January 31, 2022 Category: Parasitology Source Type: blogs

Case of the Week 670
This week ' s case was generously donated by Dr. Steven O ' Connor. He noted multiple worms in an resected appendix, and captured the following images using a dissecting microscope. Identification? (Source: Creepy Dreadful Wonderful Parasites)
Source: Creepy Dreadful Wonderful Parasites - January 24, 2022 Category: Parasitology Source Type: blogs

Answer to Case 670
Answer to theParasite Case of the Week 670:Enterobius vermicularis(pinworm) adults within the lumen of the appendix. This is a classic ectopic location for pinworm. While there is some evidence that they may cause appendicitis in this setting, it could just be an incidental coincidence, given how common  both appendicitis and pinworm infection are!For those of you not familiar with the gross appearance of the appendix, I ' ve included an annotated version below for clarification. You can also compare the size of the appendix to the rest of the intestinal tract from this Mayo Clinic image.Note that the wall o...
Source: Creepy Dreadful Wonderful Parasites - January 23, 2022 Category: Parasitology Source Type: blogs

Case of the Week 669
Here ' s another fun parasite histopathology case for you: a full-thickness section of bladder wall from an Egyptian man with invasive bladder cancer (not shown here):ClickHERE for the whole digital slide. Diagnosis? (Source: Creepy Dreadful Wonderful Parasites)
Source: Creepy Dreadful Wonderful Parasites - January 17, 2022 Category: Parasitology Source Type: blogs

Answer to Case 669
 Answer to theParasite Case of the Week 669:Schistosoma haematobiumadults and eggs - a classic case!As noted by Idzi, " Looking at site of infection and geography, most probablyS. haematobium. Section shows adult fluke and numerous non-calcified viable eggs (because I can see the cephalic gland, surrounded by nerve cells - a beautiful bullseye). In some eggs I seem to discern a small terminal spine, which supportsS. haematobium. " This is a great example, given that we rarely see the adults in tissue. Here are some of the key findings: (Source: Creepy Dreadful Wonderful Parasites)
Source: Creepy Dreadful Wonderful Parasites - January 17, 2022 Category: Parasitology Source Type: blogs

Case of the Week 668
This week ' s case is a lovely cross-section of 2 arthropods (or one cut in an odd angle) within the epidermis. The patient is a middle-aged woman with a lesion on her foot after returning from the Caribbean on holiday. Here is a still image of the digital slide:ClickHERE to zoom in for higher power.Identification? (Source: Creepy Dreadful Wonderful Parasites)
Source: Creepy Dreadful Wonderful Parasites - January 11, 2022 Category: Parasitology Source Type: blogs

Answer to Case 668
 Answer to theParasite Case of the Week 668:Tunga penetrans(likely one adult female flea) embedded in skin. Hopefully you all had a chance to look at the digital slideHERE. It is fun to zoom around on the slide and see the various features.The follow photos show some of the key diagnostic features: (Source: Creepy Dreadful Wonderful Parasites)
Source: Creepy Dreadful Wonderful Parasites - January 10, 2022 Category: Parasitology Source Type: blogs

Case of the Week 667
Happy New Year! Here ' s a great case to start off 2022. A large structure (~25 cm-long) submitted to the Clinical Parasitology lab (found in stool).  Identification? Photo is courtesy of Heather Morris.   (Source: Creepy Dreadful Wonderful Parasites)
Source: Creepy Dreadful Wonderful Parasites - January 3, 2022 Category: Parasitology Source Type: blogs

Answer to Case 667
 Answer to theParasite Case of the Week 667: Ascaris lumbricoides. This adult nematode is easy to identify when found in human stool, or expelled through the mouth, nose, or anus, due to its large size and characteristic 3 fleshy lips. Importantly, anisakid larvae also have 3 fleshy lips, and must therefore be differentiated from immatureAscariswhen expelled from the human gastrointestinal tract. This can be accomplished by examining the characteristics of the intestinal tract, mouth and tail.Thanks again to Heather for this beautiful photograph! (Source: Creepy Dreadful Wonderful Parasites)
Source: Creepy Dreadful Wonderful Parasites - January 2, 2022 Category: Parasitology Source Type: blogs

Case of the Week 666
I have a fascinating parasite for the dreaded Case of the Week 666 - not a bad way to end out 2021! I promise I will start us off in 2022 with something fun.The following was seen on a Giemsa-based stain from a liver cyst. Identification? (Source: Creepy Dreadful Wonderful Parasites)
Source: Creepy Dreadful Wonderful Parasites - December 29, 2021 Category: Parasitology Source Type: blogs

Answer to Case 666
 Answer to theParasite Case of the Week 666:Echinococcussp. degenerating protoscolex (immature scolex) and free hooklets. We can ' t say which species ofEchinococcusis present from the image alone, but it is most likely to beE. granulosus,as this is the most common species to infect humans, and it commonly forms a liver cyst that is amenable to aspiration. This is a beautiful example of rostellar hooklets in a protoscolex.Here are some other great examples ofEchinococcussp. protoscoleces and hooklets in aspirate fluide from previous posts:Case of the Week 537:Case of the Week 280:Case of the Week 514: (Source: Cr...
Source: Creepy Dreadful Wonderful Parasites - December 26, 2021 Category: Parasitology Source Type: blogs

Case of the Week 665
This week ' s case was made possible by BEI Resources and theNIH-NIAID Filariasis Research Reagent Resource (FR3) Center. They provided the materials and excellent instructions for this special experiment:These black elliptical objects measure ~550-600 micrometers long, and came dried on a piece of paper towel. I added a strip of the paper towel to a Petri dish containing distilled water and waited about 30 minutes for the action to start. Here is what happened:Here are some still shots of the action:What are these objects??Special thanks to Dr. Shelly Michalski and Teagan at the FR3 for providing the materials for th...
Source: Creepy Dreadful Wonderful Parasites - December 22, 2021 Category: Parasitology Source Type: blogs

Answer to Case 665
 Answer to theParasite Case of the Week 655: Culicidae mosquito eggs and larvae. The appearance of the eggs (darkly-colored, individual eggs, not in a raft, and without bilateral floats) is consistent withAedesspp. Since I ordered these specifically from the FR3, I can say with certainty that these are eggs those ofAedes aegpti. I hope you all enjoyed the video of the wriggling L1 larvae! (Source: Creepy Dreadful Wonderful Parasites)
Source: Creepy Dreadful Wonderful Parasites - December 21, 2021 Category: Parasitology Source Type: blogs