Case of the Week 664
 Here ' s another fun case from my lab, courtesy of our awesome parasitology technical specialist, Heather Morris. The following objects were found on screening colonoscopy.The following helpful object was found in the accompanying fluid:Identification? (Source: Creepy Dreadful Wonderful Parasites)
Source: Creepy Dreadful Wonderful Parasites - December 14, 2021 Category: Parasitology Source Type: blogs

Answer to Case 664
Answer to theParasite Case of the Week 664:Hymenolepis(Rodentolepis)nanascolex and egg.It is very unusual to see a scolex of H. nana; in my experience, it is usually only the proglottids that are removed when seen during colonoscopy. Therefore, it ' s a real treat to get to see the scolex in an actual clinical specimen! LikeTaenia soliumandDipylidium caninum, the scolex has an armed rostellum (i.e., protrusion with hooklets). The rostellum ofH. nanais generally smaller than that ofT. solium, and is often retracted. The presence of characteristicH. nanaeggs allows for definitive identification. Note the ...
Source: Creepy Dreadful Wonderful Parasites - December 13, 2021 Category: Parasitology Source Type: blogs

Case of the Week 663
This week ' s case was generously donated by Monica Jarvis and her lab. They identified the following structures in a stool wet mount. They measure approximately 160 micrometers in length. Identification? (Source: Creepy Dreadful Wonderful Parasites)
Source: Creepy Dreadful Wonderful Parasites - December 6, 2021 Category: Parasitology Source Type: blogs

Case of the Week 663
 Answer to theParasite Case of the Week 663: Not a human parasite; " Beaver bodies " .Beaver bodies are sporocysts of the unicellular, eukaryotic protozoon,Psorospermiumcf.haeckeli(Hilgendorf 1883),a parasite of crayfish. They may be seen in the stool of individuals after eating crayfish, and thus obtaining a dietary history may be helpful. Sporocysts are the host-dependent stage, and are released into the environment after the crayfish host dies. In nature, free-living amoeboids emerge from the sporocyst and are capable of infecting new crayfish.The genus Psorospermiumis located phylogenetically near the an...
Source: Creepy Dreadful Wonderful Parasites - December 5, 2021 Category: Parasitology Source Type: blogs

Case of the Week 662
This week ' s case is a stool specimen from a 52-year-old Bolivian farmer.  He complains of intermittent right upper quadrant pain, and an abdominal CT showed edema and dilation of the bile ducts.Identification?  (Source: Creepy Dreadful Wonderful Parasites)
Source: Creepy Dreadful Wonderful Parasites - November 29, 2021 Category: Parasitology Source Type: blogs

Answer to Case 662
 Answer to theParasite Case of the Week 662:Fasciola/Fasciolopsis/Echinostoma species eggs. The clinical history is most consistent with infection with the liver fluke, F. hepatica, rather than infection with an intestinal fluke. As mentioned by Bernardino, Florida Fan and SB, Fasciola giganticais also in the differential diagnosis, based on the morphology of the eggs. However, it is not found in the Americas and can therefore be excluded.Fasciolaspp.,Fasciolopsis buski,andEchinostomaeggs have a similar appearance, measuring up to 130-150 in greatest dimension, and having a small operculum. In part...
Source: Creepy Dreadful Wonderful Parasites - November 28, 2021 Category: Parasitology Source Type: blogs

Case of the Week 661
The following microfilariae were seen on Giemsa-stained preparations of whole blood following the Knott ' s concentration procedure. They are between 180 to 200 microliters in length. No travel history was initially available. Identification?Thanks to Heather Morris for these beautiful photos. (Source: Creepy Dreadful Wonderful Parasites)
Source: Creepy Dreadful Wonderful Parasites - November 16, 2021 Category: Parasitology Source Type: blogs

Answer to Case 661
Answer to theParasite Case of the Week 661:Mansonella perstansmicrofilariae.As many of you noted, this filarial worm has very small, unsheathed microfilariae. Note that the microfilariae are more slender than the eosinophils - and even the RBCs! That is one of the most helpful features. They also have a blunt tail, and the nuclei extend to the tip of the tail. (Source: Creepy Dreadful Wonderful Parasites)
Source: Creepy Dreadful Wonderful Parasites - November 15, 2021 Category: Parasitology Source Type: blogs

Case of the Week 660
This week ' s case is another histopathology finding from an eye. The entire orbit was removed because of the presence of a parasitic cyst. You can see the digital slideHERE. Identification?Here is a screen shot of the digital slide: (Source: Creepy Dreadful Wonderful Parasites)
Source: Creepy Dreadful Wonderful Parasites - November 8, 2021 Category: Parasitology Source Type: blogs

Answer to Case 660
 Answer to the Parasite Case of the Week 660: Cysticercus; larval form ofTaenia soliumAs noted by Blaine, this is " ocular cysticercosis caused byT. solium, as indicated by a single protoscolex. Coenurosis caused by a zoonoticTaeniais also a possibility, but coenuri have multiple protoscoleces, as do hydatid cysts ofEchinococcus. Sparganosis is another cestode infection that can manifest in the eyes, but they do not produce protoscoleces at all. "  Lots of great eye puns in the comments!Here are some of the key diagnostic features: (Source: Creepy Dreadful Wonderful Parasites)
Source: Creepy Dreadful Wonderful Parasites - November 7, 2021 Category: Parasitology Source Type: blogs

Case of the Week 659
This week ' s case features adigitally-scanned section of a subcutaneous nodule from the thigh of a man living in rural Senegal. The man presented with a several month history of severe itching in his lower extremities and abdomen, accompanied with a papular skin rash and focal loss of skin pigmentation. Here is a low power view of the skin and underlying nodule:Diagnosis? (Source: Creepy Dreadful Wonderful Parasites)
Source: Creepy Dreadful Wonderful Parasites - November 1, 2021 Category: Parasitology Source Type: blogs

Answer to Case 659
Answer to theParasite Case of the Week 659:Onchocerca volvulusadult worms and microfilarie. If you didn ' t already see it, check out the whole slide scanned image HERE.In this case, you can see a large subcutaneous nodule containing the adult worms (each female with  a characteristic " double barrel " uterus) and microfilariae being released into the surrounding skin. The microfilariae are the primary source of disease, as they crawl through the skin causing intense itching and inflammatory changes. They also go to the eye and cause irreversible blindness. The latter is the reason that infection is cal...
Source: Creepy Dreadful Wonderful Parasites - October 31, 2021 Category: Parasitology Source Type: blogs

Case of the Week 658
This week ' s case is a thick blood film from a patient with fever and recent travel to East Africa. Diagnosis? Would you like any additional studies? (Source: Creepy Dreadful Wonderful Parasites)
Source: Creepy Dreadful Wonderful Parasites - October 26, 2021 Category: Parasitology Source Type: blogs

Answer to Case 658
Answer to theParasite Case of the Week 658:Trypanosoma bruceiGiven the travel history and rapid onset of symptoms,T. b. rhodesienseis the most likely parasite present. This case shows very high parasitemia with numerous trypomastigotes seen on the patient ' s thick blood film. Here is the corresponding thin blood film, highlighting some of the key diagnostic features:Note that the motile flagellate form (i.e., the trypomastigote) ofT. bruceidivides by binary fission in the peripheral blood. This is in contrast toTrypanosoma cruzi,the cause of American trypanosomiasis (a.k.a. Chagas disease), in which it is the non-motile t...
Source: Creepy Dreadful Wonderful Parasites - October 24, 2021 Category: Parasitology Source Type: blogs

Case of the Week 657
This week ' s case features a Giemsa-stained thin blood film from a patient with recent travel to India. Identification? For a BONUS, can you list the different stages in images 1-4 below? (Source: Creepy Dreadful Wonderful Parasites)
Source: Creepy Dreadful Wonderful Parasites - October 19, 2021 Category: Parasitology Source Type: blogs