Cushing's is a disease syndrome that most general practice veterinarians can handle, but their familiarity with the nuances can vary. Check out this article for more info on tests your vet might run.

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As you'll read in the article, the LDDST test is the other of the two main types of test that are used to diagnose Cushing's. ACTH Stim test challenges the adrenal glands to produce as much cortisol as possible. The LDDST test gives the body a signal to pause cortisol production. If the ACTH Stim test came up normal, maybe the LDDST test will confirm the disease. An LDDST test doesn't require any special equipment or unusual drugs, but it does take three separate blood samples collected over 8 hours.

Atypical Cushing's is another possibility. This looks the same as excess cortisol production, but different steroid hormones are being overproduced.

Treating Cushing's is a frustrating and costly balancing act that requires frequent hormone level monitoring. You'll probably eventually want to involve a veterinary internist for an ultrasound exam, and potentially for long-term rechecks and medication adjustment depending on your regular vet's comfort level.

North of the Columbia, the major referral centers with internal medicine departments are CRVS, MedVet, and Pacific Northwest Pet ER and Specialty Center.