addison’s disease “the great pretender” etvma august 9, 2010 wendy blount, dvm

Addison’s DiseaseAddison’s Disease“The Great Pretender”“The Great Pretender”

ETVMA August 9, 2010ETVMA August 9, 2010

Wendy Blount, DVMWendy Blount, DVM

WendyBlount.comWendyBlount.com

Are You Missing Addison’s?Are You Missing Addison’s?

• The average vet in private practice sees 1500 The average vet in private practice sees 1500 dogs per yeardogs per year

• Addison’s Disease occurs in 0.5 dogs per Addison’s Disease occurs in 0.5 dogs per thousandthousand

• Solo practice vet should diagnose one new Solo practice vet should diagnose one new case every other yearcase every other year

• If untreated, Addison’s can be fatalIf untreated, Addison’s can be fatal• Severity variesSeverity varies• If treated, prognosis is excellentIf treated, prognosis is excellent• Median survival 7 years with treatmentMedian survival 7 years with treatment

Are You Missing Addison’s?Are You Missing Addison’s?

• What about cats?What about cats?

• Addison’s is exceedingly rare in catsAddison’s is exceedingly rare in cats

• There are less than 10 in the published There are less than 10 in the published literature that I can findliterature that I can find

• If you diagnose a cat with Addison’s If you diagnose a cat with Addison’s make sure you are adapting your ACTH make sure you are adapting your ACTH stim test to the catstim test to the cat

• Post ACTH samples at 30 & 60 minutesPost ACTH samples at 30 & 60 minutes

What Does Addison’s Look Like?What Does Addison’s Look Like?

• Breed Breed – ““Mixed” is the most common breedMixed” is the most common breed– Genetic predisposition in Genetic predisposition in

• Standard Poodle***Standard Poodle***• Portuguese Water DogPortuguese Water Dog• Bearded CollieBearded Collie• Labrador RetrieverLabrador Retriever• PointerPointer


DotDot• 2-1/2 year old SF Peke-a-Poo2-1/2 year old SF Peke-a-Poo• CCCC - She has no energy and - She has no energy and

does not eat welldoes not eat well• Sometimes she acts like she’sSometimes she acts like she’s

deaddead• ExamExam – BCS 4/6, dull mentation – BCS 4/6, dull mentation


DotDot• CBCCBC - normal - normal• PanelPanel – glucose 52 mg/dl – glucose 52 mg/dl• UrinalysisUrinalysis – SG 1.023 – SG 1.023• ElectrolytesElectrolytes – normal – normal

DiagnosisDiagnosis - Hypoglycemia of Toy Breed Dog - Hypoglycemia of Toy Breed Dog

Treatment Treatment - Multiple small meals daily, and give - Multiple small meals daily, and give Karo syrup when she acts like she’s deadKaro syrup when she acts like she’s dead


DotDot• Episodes continue with onlyEpisodes continue with only mild response to therapymild response to therapy• Exam Exam – BCS 3/6, poor muscle – BCS 3/6, poor muscle tone, dull mentationtone, dull mentation• DDx stubborn hypoglycemiaDDx stubborn hypoglycemia

– Liver diseaseLiver disease– InsulinomaInsulinoma– Occult infection/sepsisOccult infection/sepsis– Addison’s DiseaseAddison’s Disease– (Glucagon deficiency, Polycythemia)(Glucagon deficiency, Polycythemia)


DotDot• Bile AcidsBile Acids

– normal fasting and 2 hrs post mealnormal fasting and 2 hrs post meal

• Insulin and glucose levelsInsulin and glucose levels– normalnormal

• Chest x-rays and abdominal USChest x-rays and abdominal US– normalnormal

• ACTH stimulation testACTH stimulation test– Pre-ACTH – 0.2 ug/dlPre-ACTH – 0.2 ug/dl– Post-ACTH – 0.8 ug/dlPost-ACTH – 0.8 ug/dl


DotDot• Tx – Tx – Percorten q28 daysPercorten q28 days• 1 year follow-up1 year follow-up

– Dot eats like a pig and feels betterDot eats like a pig and feels better

than she has in her whole lifethan she has in her whole life– BCS increases to 6/9 in 6 weeksBCS increases to 6/9 in 6 weeks– Playful and “full of it” according to ownerPlayful and “full of it” according to owner– Dot is no longer a compliant patient and has to be Dot is no longer a compliant patient and has to be

muzzled for her Percorten shotmuzzled for her Percorten shot– I like Dot better beforeI like Dot better before


Hypoglycemia and Addison’sHypoglycemia and Addison’s

• Glucocorticoids increase gluconeogenesis Glucocorticoids increase gluconeogenesis while decreasing glucose use in tissues while decreasing glucose use in tissues via increase insulin receptor sensitivityvia increase insulin receptor sensitivity

• May be more common in toy breeds where May be more common in toy breeds where there are other predispositions to there are other predispositions to hypoglycemiahypoglycemia

• Can be severe enough to cause seizuresCan be severe enough to cause seizures

• 20-25% of Addisonians are hypoglycemic20-25% of Addisonians are hypoglycemic

• Responds the therapy in 24-48 hoursResponds the therapy in 24-48 hours


JaviJavi• 1-1/2 year old SF Great Dane1-1/2 year old SF Great Dane• 120 lbs120 lbs• CCCC – Referred for chronic cough and – Referred for chronic cough and

vomitingvomiting• Not eating for 2 daysNot eating for 2 days• ExamExam – BCS 4/6, temp 104F – BCS 4/6, temp 104F


JaviJavi• CBCCBC

– PCV 30%PCV 30%– MCV, MCH, MCHC normalMCV, MCH, MCHC normal– Neutrophils 38,000/ulNeutrophils 38,000/ul– Monocytes 2,700/ulMonocytes 2,700/ul

• panelpanel – albumin 2.2 g/dl – albumin 2.2 g/dl• UAUA – no abnormalities – no abnormalities• Electrolytes/blood gases Electrolytes/blood gases - normalnormal• Thoracic radiographsThoracic radiographs


JaviJavi


JaviJavi• DDx MegaesophagusDDx Megaesophagus

– IdiopathicIdiopathic– ObstructionObstruction

• Vascular ring anomalyVascular ring anomaly

• stricturestricture

– HypothyroidismHypothyroidism– HypoadrenocorticismHypoadrenocorticism– Myasthenia gravisMyasthenia gravis– EsophagitisEsophagitis


JaviJavi• Thyroid PanelThyroid Panel

– TSH - undetectableTSH - undetectable– T4 – 2.9 (low)T4 – 2.9 (low)– Free T4 - normalFree T4 - normal

• ACTH Stimulation TestACTH Stimulation Test– Pre ACTH cortisol – 0 ug/dlPre ACTH cortisol – 0 ug/dl– Post ACTH cortisol – 0 ug/dlPost ACTH cortisol – 0 ug/dl

• Anti Ach Receptor AntibodyAnti Ach Receptor Antibody– negativenegative


JaviJavi• DxDx

– Megaesophagus due toMegaesophagus due to

hypoadrenocorticismhypoadrenocorticism– Secondary aspiration Secondary aspiration

pneumoniapneumonia– Sick euthyroidSick euthyroid


JaviJavi• TxTx

– Prednisone 10 mg PO SIDPrednisone 10 mg PO SID– Amoxicillin 1500 mg PO BID x 4-8 weeksAmoxicillin 1500 mg PO BID x 4-8 weeks– Ciprofloxacin 500 mg PO BID x 4-8 weeksCiprofloxacin 500 mg PO BID x 4-8 weeks– Follow pneumonia with chest x-raysFollow pneumonia with chest x-rays– Javi eventually needed treatment also with Javi eventually needed treatment also with

mineralocorticoidsmineralocorticoids– Megaesophagus due to Addison’s Megaesophagus due to Addison’s

responds well to treatmentresponds well to treatment


• Hypoalbuminemia and Addison’sHypoalbuminemia and Addison’s– Albumin may have been contributed to also by Albumin may have been contributed to also by

lung infection in this caselung infection in this case– Hypoalbuminemia can be the primary Hypoalbuminemia can be the primary

presenting symptom of Addison’spresenting symptom of Addison’s


LuLuLuLu• 6 year old SF Blue Heeler6 year old SF Blue Heeler

• CCCC – referred for ICU care for – referred for ICU care for

acute renal failureacute renal failure

• CBCCBC – PCV 32% – PCV 32%

• Panel - Panel - BUN 255 mg/dl, creat 6.8 mg/dl, BUN 255 mg/dl, creat 6.8 mg/dl, phos 10.9 mg/dlphos 10.9 mg/dl

• UAUA – SG 1.016 – SG 1.016


LuLuLuLu• Electrolytes/blood gasesElectrolytes/blood gases

– K 5.9 mEq/LK 5.9 mEq/L– Na 145 mEq/LNa 145 mEq/L– pH venous 7.293pH venous 7.293– TCO2 16 mEq/LTCO2 16 mEq/L

• Abdominal US Abdominal US – normal– normal

• DxDx – acute oliguric renal failure – acute oliguric renal failure


LuLuLuLu• DDxDDx

– PyelonephritisPyelonephritis– LeptospirosisLeptospirosis– ToxicityToxicity

• Responded beautifully to treatmentResponded beautifully to treatment– IV fluid therapy x 5 daysIV fluid therapy x 5 days– Aluminum hydroxide POAluminum hydroxide PO– Ampicillin IV TIDAmpicillin IV TID


LuLuLuLu• Lulu returned in 10 daysLulu returned in 10 days

– Similar presentationSimilar presentation

• DDxDDx– Chronic renal failureChronic renal failure– hypoadrenocorticismhypoadrenocorticism

• ACTH stimulation testACTH stimulation test– Pre ACTH cortisol – 1.1 ug/dlPre ACTH cortisol – 1.1 ug/dl– Post ACTH cortisol – 1.5 ug/dlPost ACTH cortisol – 1.5 ug/dl

What Does Addison’s Look Like?What Does Addison’s Look Like?Azotemia and Addison’sAzotemia and Addison’s• Hypovolemia causing decreased renal Hypovolemia causing decreased renal

perfusion and prerenal azotemiaperfusion and prerenal azotemia• Can result in renal injury and renal Can result in renal injury and renal

azotemia if severe, prolonged and azotemia if severe, prolonged and untreateduntreated

• Hemorrhage in the GI tract can result in Hemorrhage in the GI tract can result in increased BUNincreased BUN– GI bleeding leads to more ammonia in the GI bleeding leads to more ammonia in the

coloncolon– Ammonia converted to urea in the liverAmmonia converted to urea in the liver


Azotemia and Addison’sAzotemia and Addison’s

• If no renal injury, azotemia responds If no renal injury, azotemia responds quickly to fluid therapyquickly to fluid therapy

• Responds even better if DexSP given for Responds even better if DexSP given for shock shock

• Urine specific gravityUrine specific gravity– Often mildly concentrated urineOften mildly concentrated urine– Can also be isosthenuric or hyposthenuric Can also be isosthenuric or hyposthenuric

due to medullary washoutdue to medullary washout


DocDoc• 3 year old NM Standard Poodle3 year old NM Standard Poodle• CC – CC – vomiting, weight loss, vomiting, weight loss,

drinking massive amts of water,drinking massive amts of water,

anorexiaanorexia• CBCCBC – PCV 28% – PCV 28%• PanelPanel – calcium 15 mg/dl (not lipemic) – calcium 15 mg/dl (not lipemic)• UAUA – SG 1.005 – SG 1.005• Urine cultureUrine culture – negative – negative


DocDoc• DDx hypercalcemiaDDx hypercalcemia

– MalignancyMalignancy– Primary hyperparathyroidismPrimary hyperparathyroidism– Renal diseaseRenal disease– Granulomatous inflammationGranulomatous inflammation– Hypervitaminosis DHypervitaminosis D

• Rectal exam - Rectal exam - normalnormal• Chest x-rays and abdominal USChest x-rays and abdominal US – normal – normal


DocDoc• PTHPTH – low – low• Ionized calciumIonized calcium – high – high• PTHrPPTHrP – negative – negative• ACTH stimulationACTH stimulation

– Pre ACTH cortisol – 0.8 ug/dlPre ACTH cortisol – 0.8 ug/dl– Post ACTH cortisol – 1.1 ug/dlPost ACTH cortisol – 1.1 ug/dl


PU-PD and Addison’sPU-PD and Addison’s

• Excessive sodium loss into the urine Excessive sodium loss into the urine causes medullary washout.causes medullary washout.

• Hypercalcemia can also contribute, if Hypercalcemia can also contribute, if presentpresent

What Does Addison’s Look Like?What Does Addison’s Look Like?Hypercalcemia and Addison’sHypercalcemia and Addison’s• More likely in Addisonians with more More likely in Addisonians with more

severe disease and hyperkalemiasevere disease and hyperkalemia• 29% of primary Addisonians are 29% of primary Addisonians are

hypercalcemichypercalcemic• Mechanism – unsureMechanism – unsure

– Possible hemoconcentrations of calcium Possible hemoconcentrations of calcium binding serum proteinsbinding serum proteins

– Decreased renal clearance of calciumDecreased renal clearance of calcium– Cortisol antagonizes vitamin DCortisol antagonizes vitamin D

• Responds rapidly to glucocorticoid therapyResponds rapidly to glucocorticoid therapy


ChevyChevy• 9 year old 12 lb SF Rat Terrier 9 year old 12 lb SF Rat Terrier • CCCC – taken to out-of-town vet – taken to out-of-town vet 5 days ago after having vomiting and 5 days ago after having vomiting and diarrhea on summer vacationdiarrhea on summer vacation• TxTx

– SC fluidsSC fluids– DepoMedrol 1ccDepoMedrol 1cc– Rimadyl x 7 daysRimadyl x 7 days

• Felt better for 24 hours, but now feels really bad, won’t Felt better for 24 hours, but now feels really bad, won’t eat and has “unbelievably foul diarrhea”eat and has “unbelievably foul diarrhea”


ChevyChevy• ExamExam

– dehydrated 8%dehydrated 8%– pale mucous membranespale mucous membranes– weak pulsesweak pulses– projectile stools resembling a range projectile stools resembling a range between raspberry jam to beach tar or some mixture between raspberry jam to beach tar or some mixture

thereofthereof– HR 86 beats per minuteHR 86 beats per minute– temp 97.1Ftemp 97.1F– Abdominal pain on palpationAbdominal pain on palpation


ChevyChevy• CBCCBC – PCV 35% – PCV 35%• PanelPanel

– BUN 68 mg/dl, creat 2.4 mg/dlBUN 68 mg/dl, creat 2.4 mg/dl– albumin 2.1 g/dlalbumin 2.1 g/dl– SAP 1100 U/LSAP 1100 U/L

• ElectrolytesElectrolytes – K 6.8 mEq/L, Na 142 mEq/L – K 6.8 mEq/L, Na 142 mEq/L• UAUA – SG 1.022 – SG 1.022• PT/PTTPT/PTT - normal - normal• Abdominal radiographs & ECGAbdominal radiographs & ECG


ChevyChevy

ChevyChevy

• No distinct P wavesNo distinct P waves• Tall spiked T wavesTall spiked T waves• QRS relatively normalQRS relatively normal


Bradycardia likelyBradycardia likely

due to hyperkalemiadue to hyperkalemia

ChevyChevy

• A more severe hyperkalemia ECG from a A more severe hyperkalemia ECG from a blocked tomcat with potassium 9.2 mEq/Lblocked tomcat with potassium 9.2 mEq/L



ChevyChevy• DDx – ileus, GI hemorrhage,DDx – ileus, GI hemorrhage, abdominal pain and shockabdominal pain and shock

– GI foreign bodyGI foreign body– GI ulceration GI ulceration ++ perforation perforation

• NSAID + DepoMedrol toxicityNSAID + DepoMedrol toxicity

– Hemorrhagic gastroenteritis (HGE)Hemorrhagic gastroenteritis (HGE)– AnaphylaxisAnaphylaxis– SepsisSepsis– Addison’s DiseaseAddison’s Disease


ChevyChevy• PlanPlan

– Diagnostic Diagnostic • abdominal USabdominal US• ++ barium study barium study• No endoscope immediately availableNo endoscope immediately available

– TherapeuticTherapeutic• IV fluidsIV fluids• ampicillin/enrofloxacin IVampicillin/enrofloxacin IV• Possible diagnostic surgery if perforation or foreign Possible diagnostic surgery if perforation or foreign

body is suspectedbody is suspected


ChevyChevy• DDx Azotemia with whimpyDDx Azotemia with whimpy

urine concentrationurine concentration– Dehydration/hypovolemia**Dehydration/hypovolemia**– GI hemorrhage**GI hemorrhage**– Sepsis**Sepsis**– Pyelonephritis Pyelonephritis – Addison’s DiseaseAddison’s Disease– (Early acute renal failure)(Early acute renal failure)


ChevyChevy• DDx hyperkalemiaDDx hyperkalemia

– Severe GI diseaseSevere GI disease– sepsissepsis– Addison’s DiseaseAddison’s Disease– acidosisacidosis– (Early acute renal failure)(Early acute renal failure)

• Mild to moderate hypoalbuminemia and Mild to moderate hypoalbuminemia and increased SAP could be explained by the GI increased SAP could be explained by the GI hemorrhagehemorrhage


ChevyChevy• Abdominal USAbdominal US

– No free fluid in the abdomen suggesting No free fluid in the abdomen suggesting perforationperforation

– No apparent foreign bodyNo apparent foreign body– No severe ulcerNo severe ulcer– No abnormalities, but careful interrogation No abnormalities, but careful interrogation

was difficult due to excess gas in the gutwas difficult due to excess gas in the gut• Barium study – Barium study – motility slow, but no obstruction motility slow, but no obstruction

and no filling defectsand no filling defects


ChevyChevy• Chevy remarkable better the Chevy remarkable better the

next day and eating in 48 hoursnext day and eating in 48 hours• Diarrhea improved and resolved Diarrhea improved and resolved

over 3-4 daysover 3-4 days• Tx Tx

– Amoxicillin BID x 10 daysAmoxicillin BID x 10 days– Carafate TID x 5 daysCarafate TID x 5 days– Discuss Addison’s Disease with the ownerDiscuss Addison’s Disease with the owner


ChevyChevy• Chevy did well for one month, Chevy did well for one month,

then GI signs returnedthen GI signs returned– Anorexia, vomiting, diarrheaAnorexia, vomiting, diarrhea

• ACTH stimACTH stim – Pre ACTH cortisol 1.4 ug/dlPre ACTH cortisol 1.4 ug/dl– Post ACTH cortisol 1.9 ug/dlPost ACTH cortisol 1.9 ug/dl

• 4 years later, Chevy is doing very well on 4 years later, Chevy is doing very well on Percorten therapyPercorten therapy


KelseyKelsey• 8 month old SF Rottweiler8 month old SF Rottweiler

– Owned by a vet studentOwned by a vet student

• CCCC - muscle tremors in the right - muscle tremors in the right

front legfront leg• CBCCBC – lymphocytes 6,000/ul – lymphocytes 6,000/ul• Panel/UAPanel/UA – normal – normal• ElectrolytesElectrolytes – Na 140 mEq/L, K 5.7 mEq/L – Na 140 mEq/L, K 5.7 mEq/L• ACTH stimACTH stim – baseline 1.7, post ACTH 2.0 – baseline 1.7, post ACTH 2.0


• Addison’s Disease can have many, many Addison’s Disease can have many, many different presentationsdifferent presentations

• Suspicion of Addison’s can be confirmed Suspicion of Addison’s can be confirmed only when Addison’s is on the differential only when Addison’s is on the differential diagnosis listdiagnosis list

• ACTH stim for Addison’s is a simple test that ACTH stim for Addison’s is a simple test that is easy to perform and interpretis easy to perform and interpret

• The difficulty in diagnosing Addison’s is not The difficulty in diagnosing Addison’s is not in performing complicated diagnostics, but in in performing complicated diagnostics, but in actually considering it as a possibilityactually considering it as a possibility


Blood Pressure and Addison’sBlood Pressure and Addison’s

• 90% of people with untreated Addisons 90% of people with untreated Addisons Disease are hypotensiveDisease are hypotensive

• Hypotension can remind you to put Hypotension can remind you to put Addison’s on the differential diagnosis listAddison’s on the differential diagnosis list

• Many dogs with chronic renal failure are Many dogs with chronic renal failure are hypertensivehypertensive

ACTH Stimulation TestACTH Stimulation Test

Gold standard for diagnosing Addison’s Gold standard for diagnosing Addison’s diseasedisease

ACTH gel method - DogACTH gel method - Dog

• Baseline sampleBaseline sample

• Give IU/lb ACTH gel IM, max 50 IUGive IU/lb ACTH gel IM, max 50 IU

• 2 hour post ACTH sample2 hour post ACTH sample

ACTH gel method – CatACTH gel method – Cat

• Post samples at 30 and 60 minutesPost samples at 30 and 60 minutes


Cosyntropin method - DogCosyntropin method - Dog• Baseline sampleBaseline sample• Give cosyntropin 5 ug/kg or 250ug IV/IMGive cosyntropin 5 ug/kg or 250ug IV/IM• 1 hour post ACTH1 hour post ACTH• I prefer IV because “intrafat” will not I prefer IV because “intrafat” will not

produce a stimproduce a stimConsyntropin method – CatConsyntropin method – Cat• 5 ug/kg or 125 ug/cat IM or IV5 ug/kg or 125 ug/cat IM or IV• Post samples at 30 and 60 minutesPost samples at 30 and 60 minutes


Post value <2 ug/dl confirms primary Post value <2 ug/dl confirms primary Addison’s DiseaseAddison’s Disease

• Primary Addison’s = adrenals fail to make Primary Addison’s = adrenals fail to make cortisol and/or aldosteronecortisol and/or aldosterone

Post value on secondary Addison’s can be Post value on secondary Addison’s can be as high as 3-4 ug/dl, but always less as high as 3-4 ug/dl, but always less than 5 ug/dlthan 5 ug/dl

• Secondary Addison’s = pituitary fails to Secondary Addison’s = pituitary fails to make ACTHmake ACTH

• These are harder to diagnoseThese are harder to diagnose

Resting CortisolResting Cortisol

JAVMA 231 (3) 413-416. Lennon et al (2011).JAVMA 231 (3) 413-416. Lennon et al (2011).Use of basal serum or plasma cortisol concentrations Use of basal serum or plasma cortisol concentrations

to rule out a diagnosis of hypoadrenocorticism in to rule out a diagnosis of hypoadrenocorticism in dogs: 123 cases (2000-2005)dogs: 123 cases (2000-2005)

• basal cortisol > 2 ug/dL that are not receiving corticosteroids, mitotane, or ketoconazole are highly unlikely to have hypoadrenocorticism.

• basal cortisol <= 2 ug/dL, little to no information regarding adrenal gland function can be obtained and an ACTH stimulation test should be performed.

Na:K RatioNa:K Ratio

• Aldosterone deficiency (mineralocorticoid) Aldosterone deficiency (mineralocorticoid) makes it impossible for the kidneys to makes it impossible for the kidneys to conserve sodium or excrete potassium conserve sodium or excrete potassium properlyproperly

• Cortisol deficiency precludes NaK-ATPase Cortisol deficiency precludes NaK-ATPase pump from maintaining proper Na-K balancepump from maintaining proper Na-K balance– Intracellular potassium decreasesIntracellular potassium decreases– Intracellular sodium increasesIntracellular sodium increases

• Acidosis due to hypovolemia further Acidosis due to hypovolemia further exacerbates Na-K imbalanceexacerbates Na-K imbalance– As HAs H++ moves into cells, K moves into cells, K++ moves out moves out


However….However….

• Dehydration can mask hyponatremia Dehydration can mask hyponatremia and hypochloremiaand hypochloremia

• Adrenal Addison's disease can be Adrenal Addison's disease can be purely glucocorticoid deficiency which purely glucocorticoid deficiency which has a less marked effect on electrolyteshas a less marked effect on electrolytes– Abnormalities can be subtleAbnormalities can be subtle


Thumb RulesThumb Rules• Adrenal (primary) Addison’sAdrenal (primary) Addison’s

– 86% have hyponatremia (<142 mEq/L)86% have hyponatremia (<142 mEq/L)– 95% of have hyperkalemia (>5.5 mEq/L)95% of have hyperkalemia (>5.5 mEq/L)– 4% have normal K, Na and Cl4% have normal K, Na and Cl

• ACTH deficiency (secondary HypoAC)ACTH deficiency (secondary HypoAC)– 35% have hyponatremia35% have hyponatremia– Unlikely to cause hyperkalemiaUnlikely to cause hyperkalemia– Clinical glucocorticoid deficiencyClinical glucocorticoid deficiency

• Addisonians almost never have low Addisonians almost never have low potassium or high sodiumpotassium or high sodium

• Decreased Na:K is highly sensitive but not Decreased Na:K is highly sensitive but not specific at all for Addison’s diseasespecific at all for Addison’s disease


• Mike Willard was amongst the earliest Mike Willard was amongst the earliest veterinary authors to embrace Na:K veterinary authors to embrace Na:K <27-28 as a diagnostic method for <27-28 as a diagnostic method for AddisonsAddisons

• Mike Willard, 2005 – personal Mike Willard, 2005 – personal conversationconversation““I wish I had never written that paper”I wish I had never written that paper”


ConclusionsConclusions• There are many causes of Na:K < 27-28There are many causes of Na:K < 27-28

– Only 15-17% of these are AddisonianOnly 15-17% of these are Addisonian

• Other causes include:Other causes include:– Abdominal or thoracic effusionAbdominal or thoracic effusion– Cardiorespiratory diseaseCardiorespiratory disease– AcidosisAcidosis

• Trauma or reperfusion injuryTrauma or reperfusion injury• SepsisSepsis• Diabetic KetoacidosisDiabetic Ketoacidosis• Uremia (oliguric renal failure, obstruction/rupture)Uremia (oliguric renal failure, obstruction/rupture)


ConclusionsConclusions

• Other causes include:Other causes include:– Liver failureLiver failure– ToxicityToxicity

• Mushrooms, IV fluid therapy or TPN, K sparing Mushrooms, IV fluid therapy or TPN, K sparing diuretics (spironolactone), ACE inhibitors, NSAIDsdiuretics (spironolactone), ACE inhibitors, NSAIDs

– ArtifactsArtifacts• Extreme leukocytosisExtreme leukocytosis• Hemolysis in Akitas and Shiba inusHemolysis in Akitas and Shiba inus• Running serology on EDTA plasmaRunning serology on EDTA plasma


ConclusionsConclusions• Other causes include:Other causes include:

– GI diseaseGI disease• Whipworms, hookwormsWhipworms, hookworms• PancreatitisPancreatitis• GDVGDV• ulcers, especially if perforationulcers, especially if perforation• Canine parvovirusCanine parvovirus• Canine distemper virusCanine distemper virus• severe malabsorption**severe malabsorption**

– Severe deep pyodermaSevere deep pyoderma


Conclusions – The Bottom LineConclusions – The Bottom Line

• Most Addisonians that lack both gluco- Most Addisonians that lack both gluco- and mineralocorticoid deficiencies have and mineralocorticoid deficiencies have Na:K <27Na:K <27

• Na:K <24 is a stronger indicator of Na:K <24 is a stronger indicator of hypoAChypoAC

• Na:K <15 is even stronger for AddisonsNa:K <15 is even stronger for Addisons

• Na:K >28 makes Addisons unlikelyNa:K >28 makes Addisons unlikely

Treatment of the CrisisTreatment of the Crisis

• Correct hypotensionCorrect hypotension– Death due to hypoadrenocorticism is Death due to hypoadrenocorticism is

usually due to vascular collapse (not usually due to vascular collapse (not hyperkalemia)hyperkalemia)

– 0.9% NaCl at 40-80 ml/kg/hr for 1-2 hours 0.9% NaCl at 40-80 ml/kg/hr for 1-2 hours then 1-2 ml/lb/hr for 36-48 hoursthen 1-2 ml/lb/hr for 36-48 hours

– Add 5% dextrose if hypoglycemicAdd 5% dextrose if hypoglycemic– Change to LRS when electrolytes normal Change to LRS when electrolytes normal

and BP returns to normaland BP returns to normal


• Dexamethasone 0.5-2 mg/kg initialDexamethasone 0.5-2 mg/kg initial– Then 0.01-0.05 mg/kg daily until prednisone can Then 0.01-0.05 mg/kg daily until prednisone can

be given PObe given PO

• If K > 8 mEq/L, consider treating If K > 8 mEq/L, consider treating hyperkalemiahyperkalemia– Rarely necessary after 1 hr fluidsRarely necessary after 1 hr fluids– then treat acidosis with bicarbonate if HCOthen treat acidosis with bicarbonate if HCO33/TCO/TCO22

still <12still <12– Then 0.3-0.5 U/10 lbs insulin + 5% dextrose IV Then 0.3-0.5 U/10 lbs insulin + 5% dextrose IV

fluidsfluids– Or Calcium gluconate 10% - 0.5-1 ml/kg IV to Or Calcium gluconate 10% - 0.5-1 ml/kg IV to

effect over 10-20 minutes (monitor with ECG)effect over 10-20 minutes (monitor with ECG)


• Start mineralocorticoidStart mineralocorticoid– DOCP 1 mg/lb IM q25-30 daysDOCP 1 mg/lb IM q25-30 days

• Respond within 6-8 hoursRespond within 6-8 hours

– If you don’t have DOCP in house, you can If you don’t have DOCP in house, you can use hydrocortisone IV:use hydrocortisone IV:• 1.25 mg/kg initial dose, then 0.5-1 mg/kg QID x 1.25 mg/kg initial dose, then 0.5-1 mg/kg QID x

dosesdoses• Then 0.1-0.25 mg/kg QIDThen 0.1-0.25 mg/kg QID• Then 0.1-0.25 mg/kg BID until DOCP is availableThen 0.1-0.25 mg/kg BID until DOCP is available• Not as effective as DOCPNot as effective as DOCP


• Start mineralocorticoidStart mineralocorticoid– Or Florinef Or Florinef

• Oral therapy doesn’t work well if vomitingOral therapy doesn’t work well if vomiting• 1.5-2 tablets per 5 lbs body weight daily1.5-2 tablets per 5 lbs body weight daily

• Close observation for 24-48 hours after Close observation for 24-48 hours after stopping IV fluidsstopping IV fluids

Chronic TherapyChronic Therapy

• DOCP 1 mg/lb IM q25-28 daysDOCP 1 mg/lb IM q25-28 days• Prednisone 0.1 mg/lb/day PO, and wean Prednisone 0.1 mg/lb/day PO, and wean

down to the lowest effective dosedown to the lowest effective dose– Often every other dayOften every other day– Texts say all dogs need pred, but some do Texts say all dogs need pred, but some do

well on DOCP onlywell on DOCP only– Keep pred on hand for stressful situationsKeep pred on hand for stressful situations

• Recheck in 2 weeksRecheck in 2 weeks– BUN, glucose, anything else abnormalBUN, glucose, anything else abnormal– electrolyteselectrolytes

Chronic TherapyChronic Therapy

• Recheck electrolytes in 30 daysRecheck electrolytes in 30 days– Sooner if not well Sooner if not well

• Recheck electrolytes once monthly for Recheck electrolytes once monthly for 3-6 months3-6 months– Sooner if not wellSooner if not well

• Then every 3-6 monthsThen every 3-6 months

• CBC, panel, UA q6 monthsCBC, panel, UA q6 months

Polyendocrine SyndromePolyendocrine Syndrome• Also called “Schmidt’s Syndrome” in peopleAlso called “Schmidt’s Syndrome” in people• Caused by L-P inflammation in more than one Caused by L-P inflammation in more than one

endocrine gland, causing failure of at least 2 glandsendocrine gland, causing failure of at least 2 glands• The 2The 2ndnd endocrinopathy develops 1-2 years after the endocrinopathy develops 1-2 years after the

firstfirst

– ParathyroidParathyroid– AdrenalAdrenal– GonadsGonads– ThyroidThyroid– Pancreas - DMPancreas - DM– PituitaryPituitary

– Myasthenia gravisMyasthenia gravis– VitiligoVitiligo– ITPITP– KCSKCS– SialoadenitisSialoadenitis– Rheumatoid arthritisRheumatoid arthritis– IBDIBD

Polyendocrine SyndromePolyendocrine Syndrome

• Thyroid hormones facilitate cortisol Thyroid hormones facilitate cortisol clearanceclearance

• Dogs with untreated hypothyroidism AND Dogs with untreated hypothyroidism AND untreated Addison’s disease will have untreated Addison’s disease will have conservation of cortisol levels due to lack of conservation of cortisol levels due to lack of thyroid hormonesthyroid hormones

• So they may not show signs of Addison’sSo they may not show signs of Addison’s• Treatment of the hypothyroid state can cause Treatment of the hypothyroid state can cause

precipitation of an Addisonian Crisisprecipitation of an Addisonian Crisis• If a hypothyroid dog crashes when you treat If a hypothyroid dog crashes when you treat

it, do an ACTH stimit, do an ACTH stim

addison’s disease “the great pretender” etvma august 9, 2010 wendy blount, dvm

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