Adrenocortical hemorrhage following intravenous tetracosactide in a dog with hypercortisolism

To summarize findings from a case of adrenocortical hemorrhage following tetracosactide injection during ACTH stimulation testing for monitoring of trilostane therapy in a dog.

A 12-year old neutered male dog with adrenal-dependent hypercortisolism.

4 hours after ACTH stimulation testing, the patient developed vomiting, lethargy, and abdominal pain. Abdominal ultrasound was performed before and after an ACTH stimulation test. Following ACTH stimulation testing, there was progressive bilateral adrenal enlargement and free abdominal fluid had developed. This was considered to be caused by adrenocortical inflammation and hemorrhage secondary to the synthetic ACTH analog, tetracosactide, used during stimulation testing. A resting cortisol performed 5 hours after tetracosactide injection was not consistent with iatrogenic hypoadrenocorticism.

The patient was managed with analgesia, IV fluids, and corticosteroids and made a full recovery.

To the authors' knowledge, this was the first reported case of adrenocortical hemorrhage following administration of a synthetic ACTH analog in a dog. This should be considered as a rare potential complication of ACTH stimulation testing.