Solution to the mystery posed on page 2.

The dog's blood glucose came back very low. Though that might have been explained by his recent lack of food or incessant muscle tremors, it also fit the clinical picture of adrenal disease. Luckily, there was a $45 blood test that could rule it out: electrolytes.

The electrolyte panel showed elevated potassium and decreased sodium that were consistent with Addison's disease, caused by underactive adrenal glands, although not sufficient for diagnosis.

Auggie was stabilized with intravenous fluids for rehydration and electrolytes, plus a shot of dexamethasone to improve his circulation. The final bloodwork - an ACTH stimulation test - was positive for Addison's.

Situated at the pole of each kidney, the two tiny adrenals churn out more than 30 hormones that control heart activity, blood pressure, blood flow, energy storage, immune function, sex hormone secretion, and more.

Human adrenal insufficiency (hypoadrenocorticism) was first recognized by the English physician Thomas Addison in the mid-1800s. The first canine case was reported in 1953. The breeds most affected are the standard poodle, West Highland white terrier, wheaten terrier, Portuguese water dog, Rottweiler, great Dane, and Basset hound. It is most often seen in young to middle-aged dogs, more commonly females.

The most famous purported human case was President John F. Kennedy. But Addison's is quite rare in humans and canines - two or three dogs out of 10,000, though it may be underdiagnosed due to its subterfuge.

Known as the "Great Pretender," it typically causes nonspecific problems like lethargy, weakness, dehydration, weight loss, excessive urination, vomiting and diarrhea, signs that can mimic gastrointestinal illness, heart disease, infection . . . almost anything, in fact.

Auggie had already been experiencing weakness, tremors, slowed heart rate, and dehydration. But due to the vigilance of his owners, who noticed early problems, he was diagnosed before going into "Addisonian crisis," an often-irreversible situation.

Soon after treatment, Auggie was eating and full of energy. His tremors disappeared. He will get lifelong monthly injections of Percorten-V, a synthetic corticosteroid, plus daily low-dose prednisone, regular bloodwork, and instructions to avoid stressful situations, which could aggravate his condition.

Three months later, his prognosis is for a full and healthy life.