POMC and pyruvate dehydrogenase deficiency: Approximately 80% to 85% of HAC in dogs is caused by pituitary‐dependent hyperadrenocorticism (PDH) resulting from pituitary adrenocorticotropic hormone (ACTH)‐producing adenomas, and the remaining 15% to 20% is caused by unilateral or bilateral cortisol‐producing adrenal tumors (CPATs).2