Hypoadrenocorticism Flashcards
Do cats have Addison’s disease?
Uncommon but possible
Main signalment for Addison’s disease in dogs?
Middle aged; Female dogs
Can be seen in as young as 4 m and as old as 14 yr
Most common breeds which can have Addison’s disease?
- Large:
- Small:
- Large: Great dane, poodle, Retrievers, Rottweilers, Bearded collies
- Small: West highland terrier
CS can wax and wane and mimic any other disease. T/F
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In any patient who presents with CIRCULATORY SHOCK and ↓ HR, think Addison’s disease. T/F
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Signs of circulatory shock are = Pale MM, Prolonged CRT, ↓ Temp, week pulses, mental depression/collapse
Most common signs in Addison’s disease? - - - -
- weakness and lethargy
- V , D (Can see blood in both V and D)
- PU/PD
- Signs of circulatory shock
Main CBC abnormalities expected in Addison’s disease?
- Absence of stress leukogram/ instead might see reverse leukogram
- Anemia
What type of anemia due to expect in Addison’s disease?
- N,N, NR anemia
Can be due to anemia of chronic disease or GI ulceration
Elaborate about leukogram findings in patients with Addison’s disease?
- Absence of stress leukogram (i.e. normal neutrophils and lymphocytes)
- Might show reverse leukogram (i.e. ↓neutropenia, ↑ lymphocytes)
Any MODERATELY ILL animal that presents with NORMAL or REVERSE LEUKOGRAM should raise suspicion of Addison’s disease
Chemistry findings in Addison’s disease:
- Na:K Ratio
- P
- Creatinine, BUN
- Glucose
- albumin
- cholesterol
- Na:K Ratio <27:1
- ↑ P
- ↑ BUN and creatinine due to pre-renal azotemia
- ↓ Glucose
- ↓ albumin
- ↓ cholesterol
A decreased Na:K ratio is not pathognomic for Addison’s disease and not all Addisonian patients will have low Na:K Ratio . T/F
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Other causes of low Na:K Ratio?
- Heart failure
- GI disease(Trichuris, Salmonellosis)
- Late term pregnancy
- Pancreatitis
- Neoplasia
- Body cavity effusion, uroabdomen, renal failure
Urinalysis might reveal ISOSTHENURIA in face of pre-renal azotemia. T/F
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Sodium loss → renal medullary washout → isosthenuria
With hyperkalemia, you might see marked ↓ HR i.e. < 70 . T/F
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Unlike dogs, cats usually donot show ECG abnormalities with ↑ K. T/F
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3 main ECG abnormalities with ↑ K ?
- absence of P waves
- Wide QRS
- Tented T waves
Might see VF or asystole too
3 main findings which you will expect in XRAY in case of HOC?
- microcardia
- small caudal vena cava
- microhepatica
Why is fecal analysis recommended in a suspected case of HOC?
To r/o pseudo-addison’s disease such as GI parasites (eg: whipworms)
What is the cut-off value of resting cortisol which tells you that HOC is highly unlikely.
If >2 ug/dl
If <2 ug/dl, then further testing such as ACTH stim test is needed
_______ is gold standard test for making definitive Dx of HOC
ACTH
Not LDDST
-
- correct hypoperfusion/hypovolemia
- correct ACID BASE & Electrolyte abnormalities
Which fluid type to use?
Normosol R, LRS, Plasmalyte 1-48 or A
NaCl is not the fluid of choice in cases of HOC. T/F
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Goal is to avoid increased of SODIUM by no more than _____ mEq/L per hour.
0.5-1
How much shock bolus in dog and what is limit?
20-40 mg/kg
Upto 90 ml/kg/hr
Easy way to calculate 1/4th bolus is Bw in LBS X 10
How much shock bolus in cats and what is the limit?
10-15 ml/kg
Upto 60 ml/kg/hr
1/4th shock bolus is ~ BW in Kgs X 10
Lower fluid rate be used for resuscitation in which 2 category of patients?
- pet with HEART DISEASE
- HYPOTHERMIC CAT (go with bw in kg X 10 )
Mnemonic for EOR ?
HCM PUB
H - HR C - CRT M - MM color & mentation P - Pulse quality U - UOP B - BP
So overall, first step in case of Rx for HOC is ________
Fluid resuscitation
Then constitute a fluid plan for dehydration + maintenance
Usually, when do we worry about adding colloids based on albumin levels.
If < 1.5 g/dL
But AKI is a possibility , so be very careful
How to Rx HYPERKALEMIA?
- IV Fluid resuscitation will help
- Need MRx if > 7-8 mEq/L : options are Ca Gluconate +/- R insulin & Dextrose
Elaborate Ca Gluconate dose for Rx of ↑ K?
0.5-1.5 mg/kg slow IV over 15 min
KEEP PET ATTACHED TO ECG
What to look in ECG so that the Ca Gluconate infusion can be slowed or stopped?
↓ in HR or development of new arrhythmia
Dose of R insulin & Dextrose as Rx for Hyperkalemia?
- R insulin is 0.2 U/kg IV (BW in kg/4)
- Dextrose 50% : 1 ml/kg IV
Give R insulin first, then give Dextrose
Pets might also need 2.5% dextrose CRI
CHECK blood GLUCOSE prior to giving R INSULIN . T/F
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Rx for Hypoglycemia i.e. if < 60 mg/dL
Dextrose(50%) 1 ml/kg IV diluted 1:2 to 1:4 with 0.9% Saline
Repeat the bolus PRN or start 2.5% CRI if hypoglycemia persists
PEARL: in cats with continued HYPOTENSION even after fluid resuscitation, consider checking _____ levels in blood
GLUCOSE
So, Step 1 was resuscitation and Step 2 was IV fluids + correcting hyperkalemia and hypoglycemia.
What is step 3 ?
Glucocorticoid therapy
It should be withheld until after fluid resuscitation & Hypoperfusion is withheld
Which corticosteroid does not mess with ACTH Test?
Dexamethasone
**Still to avoid any artifact, the test must be completed within 2-3 hr of giving Dexamethasone
Do you start with IV steroids or PO Steroids in hospital?
IV until pet is eating and then can be transitioned to oral medications
Main three options for IV steroids
Dex SP 0.1-0.4 mg/kg IV
Prednisolone SS 0.5 - 1 mg/kg IV
Hydrocortisone SS 5 mg/kg IV
Outpatient therapy for HOC is lifelong . T/F
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2 options for outpatient therapy for HOC?
- Fludrocortisone , or
- DOCP + Prednisolone
Fludrocortisone has both glucocorticoid & mineralocorticoid activity. T/F
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DOCP only has mineralocorticoid activity. T/F
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So we need to give Prednisone with it
Dosage of Prednisone for outpatient therapy of HOC?
0.4-0.6 mg/kg PO Daily (for ~ 1 week)→ tapered to physiologic dose of 0.2 mg/kg daily
How long can it take for dogs and cats to respond to initial therapy ?
Dogs: few hours to 1-2 days
Cats: may take upto 3-4 days
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- Antibiotics
- GI protectants & anti-emetics
- Blood tranfusions
What percentage of pets with HOC are ATYPICAL cases?
1/4th i.e. 25%
Do pets with HOC have a hx of weight loss?
Yes, ~ 50%
2 main points regarding Hx in ATYPICAL HOC?
- VOMIT more common
- Longer course of disease
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- ANEMIA
- ↓ Albumin
- ↓ Cholesterol
What 2 CBC changes do you see in REVERSE LEUKOGRAM?
↓ Neutrophils
↑ Lymphocytes
Sensitivity and specificity of ACTH Stim test.
Sensitivity is 100%
Specificity is ~ 80% (if positive = 20 false positives among 100 positives )
We should avoid 0.9% NaCl, especially if Na is < ____ mEq/L in blood .
120
Dose of HES is you need to give in case of ↓ albumin.
5-15 ml/kg
Usually, we consider R insulin + Dextrose as an Rx for ↑ K if K levels are > ___
7
Which medications to use if GI bleeding?
Omeprazole + Carafate +/- Antibiotics
Its is best to DRAW BLOOD SAMPLE for ACTH STIM test BEFORE GIVING STEROIDS. T/F
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Florinef/Fludrocortisone dose
0.1-0.3 mg/kg/d
Remember: physiologic dose of predisone is ~ 0.2 mg/kg (so almost similar )
DOCP Dose
2.2 mg/kg IM q21-25 d
check electrolytes within 7-12 days and then at day 25
