Calcinosis Cutis in a Boston Terrier Dog
A 5 year 10-month-old, male neutered, Boston Terrier presented for a 4-month history of non-healing lesions on neck, back, and abdomen.
Matthew Levinson, DVM, DACVD
Blue Pearl Pet Hospital, Northfield, IL
The owner reported his dog had an increase in appetite, drinking, and urination. CBC, chemistry, and TT4 were checked by the dog’s primary veterinarian which only revealed a mild elevation in alkaline phosphatase (256). This dog had been on several rounds of antibiotics with no improvement to the lesions and was currently on oral amoxicillin trihydrate/clavulanate potassium and topical nystatin-neomycin sulfate-thiostrepton-triamcinolone acetonide ointment. The dog was on sarolaner, moxidectin, and pyrantel) for flea, tick, and heartworm prevention.
mm: pink, moist
CRT: 1-2 seconds
On physical exam, the patient had a pot-bellied appearance and was heavily panting. Generalized hypotrichosis was appreciated on the trunk. Extending from dorsal cervical neck caudally towards the mid-dorsum were large coalescing raised erythematous and white firm, gritty plaque like lesions. The abdomen had comedones, striae, and dermal atrophy appreciated. Erythematous papules and white firm plaque like lesions also present on the abdomen and prepuce. Otoscopic examination revealed scant ceruminous debris in both external ear canals and tympanic membranes intact.
Figure 1: Hypotrichosis, hyperpigmentation of the skin, and coalescing erythematous plaque-like lesions extending from the dorsal cervical to mid dorsum.
Figure 2: Striae, comedones, erythematous and yellowish to white mineralized plaques on the abdomen and prepuce.
Figure 3: A closer look at the striae and erythematous and yellowish to white mineralized plaques on the abdomen.
Initial diagnostics included skin scraping, cytology, and ACTH stimulation:
Skin scraping was negative for mites and eggs
Cytology of the affected skin revealed corneocytes, nuclear streaming, pyogranulomatous inflammation, mineralized salts, and scarce cocci and rods.
ACTH stimulation found baseline cortisol of 4.8 ug/dL and a post-cosyntropin cortisol level of 50.0 ug/dL
Calcinosis cutis secondary to hyperadrenocorticism
Mild secondary bacterial dermatitis