Lecture 10 2/20/25 Flashcards
Which parasite can cause a condition known as pseudo-Addison’s?
T. vulpis
What are the characteristics of the ACTH stim test for Addison’s?
-definitive; can rule disease in or out
-pre- and post-ACTH cortisol that are both < 2 ug/dL are diagnostic
-measures adrenocortical reserve
Which screening tests can be used for Addison’s?
-baseline cortisol; > 2 ug/dL rules out Addison’s
-abdominal ultrasound to assess adrenal size
What are the steps of the ACTH stim test in dogs?
-collect baseline cortisol sample
-give ACTH
-collect post-sample 1 hour later
-do not feed or stress during sampling
What are the steps of the ACTH stim test in cats?
-collect baseline cortisol sample
-give ACTH
-collect post-samples 30 minutes and 60 minutes later
-do not feed during sampling
What are the characteristics of primary/typical addison’s dz?
-adrenocortical atrophy or destruction
-typically autoimmune destruction
-immunosuppression is not helpful; tissue is already destroyed, suppression just weakens body’s immune system
-low Na, high K
What are the characteristics of secondary/pituitary addison’s?
-can be due to pituitary dz or be iatrogenic
-lack of ACTH from pituitary
-aldosterone secretion not affected
-Na and K are normal
What are the characteristics of atypical addison’s?
-zona fasciculata atrophy only
-zona glomerulosa spared; mineralocorticoids are available
-Na and K are normal
What is critical illness-related corticosteroid insufficiency?
-relative adrenal insufficiency described in critical patients
-temporary; corrects with resolution of illness
-typically does not require specific treatment; can do short course of glucocorticoids
What is the long-term medical therapy for typical addison’s?
-prednisone pills daily
-DOCP injections monthly or florinef pills daily (mineralocorticoids)
Which aspect of typical addison’s tx is not needed in atypical tx?
DOCP/florinef
What is the supportive care for addisonian crisis?
-IV fluids
-dextrose
-calcium gluconate
How does DOCP/percorten/zycortal differ from fludrocortisone/florinef?
-DOCP is mineralocorticoid only and is a monthly injection
-florinef is glucocorticoid and mineralocorticoid and is a daily pill
What are the steps to treatment for addisonian crisis?
-IV cath
-check CBC/chem/lytes, UA, and BP
-aggressive fluid resuscitation; hypertonic followed by isotonic
-ACTH stim test
-slow correction of low sodium
-IV dextrose for hypoglycemia
-IV dextrose, calcium gluconate, +/- regular insulin for severe/refractory hyperkalemia
-IV dexamethasone
-DOCP or florinef
What are the characteristics of addison’s maintenance?
-life long glucocorticoid replacement
-life long mineralocorticoid replacement
-increase dose 2-3x during stress
-avoid withdrawal
-titrate to avoid signs of addison’s or cushing’s
What are the characteristics of Addison’s in cats?
-primary addison’s is rare; most often idiopathic when it occurs
-diagnosis anywhere between 18 months and 14 years
-naturally occurring secondary addison’s has not been reported in cats
-secondary addison’s is typically iatrogenic
What are the treatment steps for addison’s in cats?
-long-term glucocorticoid replacement as in dogs
-mineralocorticoid replacement with fludrocortisone acetate
What is the prognosis for addison’s?
-long-term prognosis is good to excellent
-can take several days to start responding to treatment
What should be monitored in the case of acute addisonian crisis?
-ECG
-serial BP
-serial electrolytes +/- blood gas
-azotemia
-serial blood glucose
-hydration status
-physical exam/clinical signs
What maintenance monitoring should be done about 2 weeks after beginning DOCP?
DOCP dose assessment
-check electrolytes; want return to normal
-clinical signs resolved
-chemistry mostly normal
-adjust dose if needed
What maintenance monitoring should be done about 1 month after beginning DOCP?
DOCP duration assessment; determine if time between treatment is adequate
