Case of the Week 693

 This week's case was kindly donated by Dr. Mike Mitchell and his laboratory. The patient is a middle-aged man with fever, intermittent cough, headache and mental status changes. He had a history of lymphoma and was receiving maintenance immunosuppressive chemotherapy. Of note, he had several episodes of bacteriemia and progressively worsening pulmonary infiltrates. He was originally from Sub-Saharan Africa but had been living in the United States for several decades. 

The following are images from a duodenal aspirate:

What is your diagnosis?

Answer to Case 693

Answer to Parasite Case of the Week 693: Strongyloides stercoralis larvae

As many of you mentioned, the large number of larvae is very concerning for strongyloides hyperinfection, so an urgent call to the treating physician is indicated. 

The single larva seen here is an rhabditiform (L1) larva. It has a short buccal canal (shown) and prominent genital primordium.

Case of the Week 692

 This week's case is a bit different in that it wasn't actually alive. Instead, it is a stunning glass artwork of an object that is important in the world of human clinical parasitology. What am I showing here?

This amazing work is by Jane Hartman (@trilobiteglass). You can find her Etsy shop HERE! (Posted with permission)

Answer to Case 692

Answer to the Parasite Case of the Week 692: Female copepod with a Dracunculus medinensis larva inside. This stunning glass art was made by Jane Hartman (@trilobiteglass) and gifted to me by my friend and colleague, Dr. Audrey Schuetz (@schuetz_audrey). 

Here are some of the key features:

This case is particularly special since it was the topic of the very first unknown case I ever posted on this blog - way back in 2007! You can see it here: Parasite Case of the Week 1.

Thanks to everyone who has stuck with me along the way - 7 years and 691 posts later! - and to those of you who have joined along the way.

Case of the Week 691

This week's case was generously donated by Dr. Nicole Brammer Hubbard. Several of the following objects were removed from ear of a child after the parents noticed a bloody discharge (!)  Identification?

Answer to Case 691

 Answer to Parasite Case of the Week 691: Fly larva, consistent with Lucilia species, (or as Florida Fan noted, "I love Lucy!") 

There are numerous keys for identifying fly larvae, including the freely-available CDC pictorial keys (https://www.cdc.gov/nceh/ehs/publications/pictorial_keys.htm) and a simplified key that Blaine and I published in our review on Laboratory Identification of Arthropod Ectoparasites (Clinical Microbiology Reviews). These keys are very easy to use once one is familiar with the basic morphologic parts of fly larvae (e.g., spiracular plates, mandible). 

Identification to the species level is based on several features including the general body characteristics, arrangement of cuticular spines, mouthparts, and the posterior spiracles. In this case, Dr. Brammer Hubbard was able to get beautiful photographs of all of the key morphologic features so that we can easily make our identification. These show us that there is not an accessory oral sclerite on the mandible, the posterior spiracular slits are straight, and the spiracular plate and button are not heavily sclerotized. This leads us to a final identification of Lucilia species. 

Lucilia is a cause of facultative wound myiasis rather than obligatory myiasis. If you are interested, you can read about it in the chapter that Blaine and I wrote on "Encyclopedia of Infection and Immunity: Parasites of the Ear." (Let me know if you'd like a copy 😊)

 

Case of the Week 690

This week's case is in honor of @JMGardner who showed a beautiful example of this finding a little while ago. This one is not quite as good, but still diagnostic. The digital slide can be viewed HERE. This is a low power view:

What information can be gleaned from this biopsy, and what would have been the preferred method for identification?