Canine Cushing's Case Files: The ins and outs of detection and treatment—Case file: Holly (Sponsored by Dechra Veterinary Products)


Canine Cushing's Case Files: The ins and outs of detection and treatment—Case file: Holly (Sponsored by Dechra Veterinary Products)

Oct 01, 2013

Case file: HOLLY
8-year-old spayed female German shepherd weighing 33.3 kg (73.3 lb)

Patient history and initial referral findings

Dr. Christopher G. Byers
Holly's primary care veterinarian had diagnosed hyperadrenocorticism based on her history and clinical signs and the results of routine laboratory tests and a low-dose dexamethasone suppression test. Holly was treated for hyperadrenocorticism with trilostane (75 mg given orally once a day) obtained from a compounding pharmacy.

Six months later, Holly developed lethargy, vomiting, and abdominal distention and had markedly increased hepatic enzyme activities. The trilostane was discontinued and Holly was referred to MidWest Veterinary Specialty Hospital for an abdominal ultrasonographic examination. Peritoneal effusion secondary to a ruptured gallbladder mucocele was identified, and Holly was successfully managed with cholecystectomy and appropriate supportive critical care.

Follow-up referral evaluation

Figure 1. When presented, 8-year-old Holly was experiencing increased panting, polyuria, and polydipsia. She had patchy dorsolateral truncal alopecia and a pendulous abdomen.
About one month after recovery from the cholecystectomy, Holly was again presented to MidWest Veterinary Specialty Hospital for evaluation of hair loss, increased panting, and polyuria and polydipsia. Holly's owners stated that she was otherwise clinically normal at home. Abnormalities identified on physical examination were patchy dorsolateral truncal alopecia with cutaneous hyperpigmentation, a pendulous abdomen, and moderate dental tartar with gingival inflammation (Figure 1).

The results of a serum chemistry profile revealed increased alkaline phosphatase, alanine aminotransferase, asparagine aminotransferase, gamma-glutamyl transferase, and creatine kinase activities; hyperbilirubinemia; and hypercholesterolemia. The complete blood count results identified leukocytosis with a mature neutrophilia and monocytosis. Urinalysis showed a urine specific gravity of 1.027, bilirubinuria (1+; reference range = negative) and trace proteinuria (< 100 mg/dl; reference range = negative). All of these findings were deemed consistent with hyperadrenocorticism.

Confirmatory test results

The results of an adrenocorticotropic hormone (ACTH) stimulation test revealed a baseline cortisol concentration of 12.4 µg/dl (reference range = 2 to 6 µg/dl) and a one-hour post-ACTH cortisol concentration of 28.7 µg/dl (reference range =8 to 18 µg/dl). The abnormal ACTH stimulation test results in combination with Holly's history, clinical signs, and other abnormal laboratory test results confirmed hyperadrenocorticism.

The previous abdominal ultrasonographic examination and direct adrenal visualization at the time of exploratory laparotomy for cholecystectomy identified that both adrenal glands were normal size and shape, which is consistent with pituitary-dependent hyperadrenocorticism. Medical therapy options were discussed with the family, who elected treatment with VETORYL® Capsules (trilostane).

Treatment and follow-up

Treatment with VETORYL Capsules was begun at a dose of 3.6 mg/kg given orally once daily in the morning with food. The family was advised to keep a daily journal to document Holly's frequency of panting, water consumption, urination frequency, appetite voracity, and activity level. They were also asked to document any episodes of vomiting or diarrhea and to call with any questions or concerns. Holly's family was also advised to consult with her primary care veterinarian regarding prophylactic dental care.