Case studies can sometimes be fun to test your medical knowledge! Read through the case study below to answer some basic terminology questions and then make your “diagnosis.” Scroll to to the bottom to see the correct answers.
This is Boo, a 2 year old male neutered Pit Bull who was recently rescued. When he was adopted, he had a few areas of hairloss which were attributed to allergies. The owner reports he scratches a little, but not excessively. Now his skin is very red and he is continuing to lose hair and has crusty lesions. Benadryl has not helped.
Question 1: What is the correct medical term for “itchy”?
Question 2: What is the correct medical term for redness of the skin?
Question 3: What is the correct medical term for loss of hair or baldness?
The veterinarian asks you to do a skin scraping. You perform a deep skin scraping and look at the slide under the microscope:
Question 4: What organism do you see in this slide?
a) Demodex canis
b) Trichophyton verrucosum
c) Sarcoptes scabiei
d) Otodectes cynotis
Great Job in making you “diagnosis!”
Now, scroll to the bottom for the correct answers and explanations:
Keep scrolling down…
Keep scrolling down…
Question 1: Answer C- Pruritis is the condition of being itchy. An animal that is itchy is pruritic. Dermatitis is just a general term for inflammation of the skin. Papules are small raised inflammatory lesions on the skin which do not contain pus. Urticaria are hives.
Question 2: Answer A- Erythema is redness. Red skin can be described as erythematous. Cyanotic skin or mucous membranes would appear blue or purple due to lack of oxygen. Petechiae are small bruises on the skin, often caused due to a low platelet count. Lichenified skin appears abnormally thickened due to chronic inflammation or infection (looks like elephant skin).
Question 3: Answer D- Alopecia is the term used for a bald patch or area of hair loss. Folliculitis means inflammation of a hair follicle. Pemphigus is a dermatologic automimmune disorder. Atrophy is the shrinking or wasting of a body part or tissue.
Question 4: Answer A- Demodex canis. This is a cigar shaped mite that lives in the hair follicles, which is why a deep skin scraping is usually required to make the diagnosis. It is a normal part of the skin flora, but can overgrow and cause clinical disease in some patients like Boo. This mite is not typically itchy, however, Demodex patients often have secondary bacterial or fungal infections which do cause pruritis. In addition to treatment for the Demodex, patients with severe infections often need antibiotics or antifungal therapy. Demodex is most commonly seen in puppies and young dogs. It is NOT contagious to other animals and is not zoonotic.
Sarcoptes is the superficial mite which causes “scabies” and is contagious. It causes intense pruritis. Trichophyton is a dermatophyte (one cause of ringworm). Otodectes is the ear mite.