HYPERadrenocorticism Flashcards

Question

Canine Hyperadreonocorticism Clinical signs Cardiovascular effects

Answer 1

sodium and water retention results in hypertension and hypervolemia

Answer 2

Anorexia, behavioral changes, and disorientation, circling, central blindness, or other neurologic signs 10-15% of dogs with PDH in association with a macroademona

Answer 3

Negative feedback on pituitary gonadotropin secretions Decrease in testicular androgen production in males Anestrus in females

Answer 4

Myotonia facial nerve paralysis Diabetes mellitus Proteinuria / hypoalbuminemia Pulmonary thromboemboli Hypercoagulable state

Answer 5

Can be a diagnostic delimma because no test is highly sensitive or specific Cortisol cna be elevated due to non-adrenal illness Clinical signs compatible but diagnostics don't support clinical suspicion Other steroid production causing clinical signs

Answer 6

* CBC * stess leukogram * Thromobocytosis * Chemistry * Elevated liver enzymes (ALP\>ALT) * ALP: * Primarily due to the GC-induced isoenzyme * Secondary to mild intrahepatic cholestasis from glycogen deposistion * ALT: * variable mild hepatic necrosis, glycogen storage, swollen hepatocytes * Hypercholestrolemia * due to stimulated lipolysis * Hyperglycemia * Urinalysis * always perform with HAC regardless of urine sediment * Blood Pressure * hypertensive * Radiographs * Hepatomegaly, ectopic clacification, Adrenal tumor, Osteoporosis, Cystic Calculi

Answer 7

Two step process * Screening: * Confirms clinical suspicion of HAC * Differentiating Test * Choose appropriate treatment plan * Medical - Pituitary dependent * Surgical - adrenal dependent

Answer 8

THere is NO Perfect test A postive test result should never be the sole basis of your diagnosis Adrenocorticotropic hormone stimulation test Low Dose Dexamethasone Suppression test Urine Cortisol:Creatinine ratio

Answer 9

Sensitivity - PDH Specificity - PDH and ADH Chronic stress or non-adrenal illness may produce test results suggestive of HAC Advantages: Fast - 1 hour to preform good choice if non-adrenal illness is suspected ONLY WAY TO DIAGNOSE IATROGENIC HAC Disadvantages - EXPENSIVE

Answer 10

Procedure: baseline cortisol; injection dexamethasone IV, Collect serum samples 4 hrs and 8 hrs post injection Interpretation: Normal - suppressio of plasma cortisol at 4 and 8 hrs HAC - no suppression at 4 or 8 hrs PDH - may exhibit suppression form baseline cortisol May exibit normal suppression at 4 hrs but escape into anbormal range at 8 hrs

Answer 11

Good choice for non-adrenal illness is not suspected Is a differentiating test if suppression followed by escape Inexpensive

Answer 12

Takes 8 hours to perform

Answer 13

Best used to determine if a dog does NOT have HAC Sensitivity - nearly 100% Consistently high serum cortisol results in proportionately high amount excreted in the urine Negative Results rules out HAC

Answer 14

differentiate pituitary dependent vs. adrenal dependent hyperadrenocorticsm Abdominal ultrasound high dose dexamethasone suppression test endogenous ACTH meausurement

Answer 15

bilateral adrenal hypertrophy overlap in normal adrenal gland size and hypertrophy Threshold of 7.4mm diameter = 77% sensitivity and 80-91% specificity

Answer 16

Unilateral adrenal enlargement, contralateral atrophy Presence does not equal functional adrenal mass

Answer 17

Procedure - same as LDDST except use 0.1mg/kg ADH - do not suppress at 4 or 8 hours PDH - will suppress at 4 or 8 hours Failure to suppress means the odds of having PDH vs. ADH is 50-50 because ADH never suppress but PDH is the most common form

Answer 18

Not used clinically Advantages - can positively differentiate PDH vs. ADH Diasadvantages - difficult to measure

Answer 19

diagnosis of adrenal tumors pituitary tumors when macroadenoma present

Answer 20

more accurate for visualization of small pituitary tumors but only 50% of dogs with PDH will have identifiable microadenoma

Answer 21

TREATMENT OF CHOICE Necrosis of adrenal cortex - fasiculata and reticularis most susceptibel Enzyme inhibitors in steroid synthesis pathways trilostane ketoconazole L-Deprenyl

Answer 22

FDA approved for dogs - therapy of choice in US Competitive inhibitor of 3B hydroxysteroid dehydrogenase → inhibits production of progesterone and 17-hydroxyprogesterono → inhibits adrenal cortisol and aldosterone

Answer 23

sings improve within a few weeks of starting drug. Marked improvement within 2 months. enzyme inhibition rapidly reversible if dugs is discontinued

Answer 24

transient vomiting, diarrhea, lethargy rarely, hypoadrenocorticism may develop Adrenal necrosis causing death is a rarely reported adverse effect

Answer 25

There is no single protocol shown to be superior to another ACTH stimulation test is recommended on the trilostane insert. 10-14 days after starting trilostane 2 weeks after dose increase every 3 months for the long term

Answer 26

TREATMENT OF CHOICE unilateral adrenalectomy if metastatic disease and invasion absent of adjacent structures is absent

Answer 27

Perioperative complications: hemorrhage, pulmonary thromboembolism Post-Operative complications: acute adrenal insufficiency, organ fialure/vascular

Answer 28

MST 36 month if benign and easily removed and the patient survives the first two weeks Malignant tumors have less favorable prognosis

Answer 29

Mitotane: necrosis of adrenal cortex, may also have effects on metastatic lesions, often requires longer induction phase and higher dose for maintenance pase Trilostane: no efficacy reported

Answer 30

most treated dogs experience imporved quality of life and show a reduction in clinical signs, reduced morbidity, and alleviation of long-term complications associated with untreated disease Persistence or development of CNS signs carries a guarded to poor prognosis without intervention to address pituitary enlargement

Answer 31

benign adrenal tumors carry a good/excellent prognosis after successful removal. Malignant tumors have a guarded to grave prognosis