Cholecalciferol Flashcards
What is the source of toxicosis?
Ingestion of bait, secondary toxicosis, large doses of vitamin D, poisonous plants
What is another name for cholecalciferol?
Vitamin D3
Which animals are more frequently poisoned?
Dogs and cats
Cats are more sensitive
What are three predisposing factors?
Renal disease, hyperparathyroidism and ingestion of high Ca/P in diet
T/F: Cholecalciferol has a narrow safety margin?
TRUE-Small amount is DEADLY
How does cholecalciferol get to the liver?
Binds to serum vitamin D binding protein
Once in the liver, what happens to cholecalciferol?
Metabolized by hydroxylation to 25-hydroxycholecalciferol
What is the main circulating form of cholecalciferol?
25-hydroxycholecalciferol
What does 25-hydroxycholecalciferol get metabolized to in the kidney?
1,25-dihydroxycholecalciferol (calcitriol)
What is the most potent form of cholecalciferol?
Calcitriol
What does calcitriol do to Ca/P levels?
Increases Ca & P by stimulating renal reabsorption and Ca release from bone
T/F: Vitamin D can be excreted in milk in toxic levles
TRUE
What is a side effect of the increased Ca/P levels?
Tissue mineralization
What ions are lost due to increased Ca/P levels?
Na and K
What is the major cause of death in these patients?
Cardiac/renal failure
How long does it take for CS to appear?
24-36 hrs
What are some major systems affected due to this poisoning?
GI, Renal, CV possibly neuro signs
What is a major lesion seen in the GI/heart?
White chalky deposits
What are postmortem specimens that should be obtained for laboratory diagnoses?
Bile/Kidney
T/F: Increased levels of PTH will be a result
FALSE
Decreased levels- the Ca/P is increased, your body will try and compensate by decreasing the amount of Ca/P redistributed through the body
What treatment can be used to decrease Calcium to normal levels?
Pamidronate disodium (inhibitor of bone resorption)
