Canine Hypoadrenocorticism (Addison’s Disease)

Angela BryanISU College of Veterinary Medicine

Class of 2018

WHAT IS ADDISON’S?• An inadequate production of steroidal hormones,

mineralcorticoids and/or glucocorticoids, within the body

• Follows destruction of the adrenal cortex of the adrenal gland, usually from an immune-mediated process

• Mineralcorticoids - Produced by the adrenal gland - Maintain normal blood volume, normal cardiac output, and water and electrolyte balance

Glucocorticoids- Produced by the adrenal gland- Cortisol is a glucocorticoid that gives an animal the ability to respond to stress

Figure: http://whitney05.hubpages.com/hub/Addisons-Disease-Dogs

WHAT ARE THE SYMPTOMS?Acute Presentation

http://vetneuromuscular.ucsd.edu/cases/2006/nov06.htmlhttp://cmapsconverted.ihmc.us/rid=1N9J4DSHV-LJCBLF-156M/Resources%20for%20Dehydration%20and%20Fluid%20Therapy

- Severe Dehydration

- Shock - Slow Heart Rate

https://www.vetarena.org/dogs-health-care-articles/591/sinus-bradycardia-dogs-symptoms-diagnosis-treatment.html

Vomiting and diarrhea

WHAT ARE THE SYMPTOMS?

- Weight loss - Anorexia

- Trembling - Lethargy

- Hypothermia - Diarrhea

- Weakness - Excessive drinking

- Collapsing - Excessive urination

Chronic Presentation

Figure 1: http://blogs.ntm.org/rachel-chapman/2012/07/19/an-old-nahuatl-tale/Figure 2: https://www.pinterest.com/elizabeth9277/my-unhealthy-obsession-with-french-bulldogs/Figure 3: http://thewilsonconcept.com/blog-2/Figure 4: http://www.vetwest.com.au/pet-library/house-soiling-elimination-and-marking-problems-in-dogs

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HOW IS IT DIAGNOSED?• ACTH Stimulation Test in Canines

– Step 1: Blood collection• Obtain plasma or serum sample for baseline cortisol

levels within the body

– Step 2: Intravenous injection of cosyntropin • Cosyntropin is a synthetic form of ACTH

– Step 3: Blood collection post injection• Obtain plasma or serum sample for cortisol

measurement 1 hour later

WHAT IS “ACTH”?• “Adrenocorticotropic hormone”

• Stimulates the body to produce cortisol in response to stress

• Cortisol is produced by the adrenal gland

• Damage to the adrenal gland will interfere with the production of cortisol

• ACTH is NOT able to stimulate the adrenal gland to produce cortisol in the Addisonian patient

HOW DO YOU INTERPRET THE TEST RESULTS?

• Normal: Baseline plasma cortisol levels INCREASE after the ACTH injection

• Addison’s Disease: Baseline plasma cortisol levels are extremely low and DO NOT INCREASE after the ACTH injection

Figure: http://www.endocrinevet.info/2011/04/q-atypical-addisons-disease-in-dogs.html

HOW CAN IT BE TREATED?1. Correct the low blood pressure2. Correct the low blood volume3. Provide glucocorticoid and

possible mineralocorticoid replacements

4. Restore the electrolyte balance

5. Restore the acid-base balance

Figure: https://en.wikibooks.org/wiki/Structural_Biochemistry/Prednisone

MEET “DAISY”• 6 year old Maltese

• Previously diagnosed with Addison’s Disease– History of Addison’s for 4-5 years

• Presented to IVS due to an Addisonian crisis

HOW DID DAISY PRESENT?• Bloody diarrhea• Vomiting• Tremors • Lethargy

HOW DID IVS HELP?• Medical management

– Dexamethasone SP• Steroid used to replace glucocorticoids within the body

– Cerenia• Anti-nausea medication to prevent any further vomiting

– Metronidazole• Anti-bacterial medication to help with Daisy’s diarrhea

– Vetstarch • To help support low protein levels in the blood

LIFE AFTER THE DIAGNOSIS…• Daisy’s condition requires continued medical

management throughout her lifetime– Oral medications daily (glucocorticoids)– Injections monthly (mineralocorticoids) : administered

by a veterinarian at first, but may be able to be administered at home eventually

• Daisy will also require periodic checkups from her regular veterinarian throughout her life : About every 3-6 months

DAISY’S RECOVERY• After multiple days in the hospital, Daisy was

able to make a full recovery

• With medical management, Daisy will be able to live a normal, lengthy life like any other dog!

IF YOUR DOG HAS ANY OF THE SYMPTOMS DESCRIBED, PLEASE SEEK VETERINARY CARE IMMEDIATELY!!

REFERENCES• Plunkett SJ. 2001. Emergency

Procedures for the Small Animal Veterinarian. 2nd ed. London: Harcourt Publishers Limited.

• Silverstein DC, Hopper K. 2015. Small Animal Critical Care Medicine. 2nd ed. St. Louis, MO: Elsevier Saunders.

• Wingfield WE, Raffe MR. 2002. The Veterinary ICU Book. Jackson, WY: Teton NewMedia.