Term
What are the major hormone players in calcium metabolism? |
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Definition
-parathyroid hormone -vitamin D (calcitriol) |
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Term
What are the major organ players in calcium metabolism? |
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Definition
-parathyroid glands -kidneys -bone -intestine |
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Term
Which organ secretes parathyroid hormone? What stimulates its secretion? What inhibits its secretion? |
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Definition
-parathyroid glands -Stim by dec iCa or inc P -inh by calcitriol |
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Term
What does parathyroid hormone go? |
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Definition
-inc Ca resorption from bone and kidney -inc activation of calcitriol: inc Ca and P absorption by intestine, kidney, and bone -dec P resorption from kidney |
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Term
What is the primary source of Vitamin D? What happens to it in the liver? In the kidney? |
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Definition
-diet -hydroxylation in liver: 25-hydroxyvitamin D -hydroxylation in kidney: 1,25- dihydroxyvitamin D (aka calcitriol) |
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Term
What activates Vitamin D? What does it do? |
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Definition
-activation stim by PTH -inc Ca and P resorption from bone, kidney, and absorption in intestine |
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Term
What is the purpose of calcium in the body? |
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Definition
-cofactor for enzymes -cell membrane stability -secondary intracellular messenger -nerve conduction -NM transmission -muscle contraction -smooth muscle tone -bone formation -glycogen metabolism |
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Term
What are the three types of Ca in the body? Which form(s) is/are bio active? |
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Definition
- ionized calcium (aka free ca), protein-bound ca, complexed ca -ionized ca is only bio active form |
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Term
What are the clinical signs of hypercalcemia? |
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Definition
-PU/PD -lethargy & weakness -GI signs: vomiting, diarrhea, inappetence -shivering -constipation -signs of acute kidney injury: due to calcification of renal tubules |
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Term
The causes of hypercalcemia is summarized by the acronym HARD IONS G? |
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Definition
-H: hyperparathyroidism -A: Addison's -R: Renal disease -D: Vit D toxicity (especially cats) -I: idiopathic -O: osteolytic lesions -N: neoplasia -S: spurious or lab error -G: granulomatous dz |
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Term
What are the common causes of hypercalcemia? |
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Definition
-lymphoma -hypoadrenocorticism -primary hyperparathyroidism -chronic kidney dz -idiopathic in cats |
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Term
What is the mechanism behind autonomous PTH secretion? |
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Definition
-primary hyperparathyroidism |
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Term
What is the physiology behind humoral hyprcalcemia of malignancy? |
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Definition
-PTHrP -other factors: IL-1, TGF, TNF, etc |
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Term
What is the physiology behind Addison's causing hypercalcemia? |
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Definition
-dec calciuresis -hemoconcentration -inc complexed Ca |
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Term
What is the physiology behind hypercalcemia due to kidney dz? |
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Definition
-dec calciuresis -parathyroid hyperplasia (due to inc P) -dec inactivation of PTH -inc complexed Ca |
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Term
What is the physiology behind hypercalcemia due to granulomatous dz? |
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Definition
-macrophages activating Vitamin D: take over the kidney's usual job |
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Term
What is the physiology behind hypercalcemia due to osteolytic dz? |
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Definition
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Term
How do we treat hypercalcemia? |
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Definition
-treat underlying cause -0.9% NaCl diuresis to promote calciuresis -Furosemide: promote calciuresis -Bisphosphonates (Pamidronate, alendronate): inh osteoclasts -Glucocorticoids: dec inflammation and promote calciuresis |
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Term
Are dogs or cats more likey to have primary hyperparathyroidism? What is usually the cause? Typical age? |
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Definition
-dogs >>>>> cats -parathyroid adenoma >>>>>> carcinoma -over 7y |
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Term
Which dog breed is most likely toget primary hyperparathyroidism? |
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Definition
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Term
What are the clinical signs hyperparathyroidism in dogs? |
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Definition
-PU/PD -listlessness 0incontinence -weakness -inappetence -lower UTI -muscle wasting -vomiting -shivering -constipation -stiff gait |
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Term
What are the clinical signs of hyperparathyrdoism in cats? |
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Definition
-anorexia -GI signs: vomiting, diarrhea, constipation -PU/PD -lower urinary tract signs -neuro signs |
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Term
What diagnostic tests do we run on hyperparathyroidism? |
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Definition
-physical exam: rule out other causes of hypercalcemia -CBC: normal -UA |
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Term
What does a UA show for hypercalcemia due to hyperparathyroidism? |
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Definition
-hematuria -pyuria -bacteriuria |
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Term
What results do we see on biochem analysis for hypercalcemia due to hyperparathyroidism? |
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Definition
-hypercalcemia -hypophosphatemia -azotemia is uncommon |
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Term
What definitively diagnoses hyperparathyroidism? |
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Definition
-paired PTH and ionized Ca: inc ionized Ca, inc/normal PTH, PTHrP negative |
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Term
What is the significance of PTHrP being positive? |
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Definition
-highly suggestive of cancer |
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Term
What do we see on US that diagnoses hyperparathrydoism? |
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Definition
-abnormal parathyroid gland(s) |
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Term
What are our three forms of hyperparathyroidism treatment? |
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Definition
-Parathyroidectomy: most only have one abnormal parathyroid gland -percutaneous US guided RF ablation: heat destroys parathyroid gland -percutaneous US guided ethanol ablation: ethanol destroys parathyroid gland |
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Term
What are the major components of post-treatment management for hyperparathyroidism? |
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Definition
-normal parathyroid gland atrophied -oral calcitriol -oral calcium supplementation |
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Term
What is hungry bone syndrome? How do we treat it? |
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Definition
-rebound syndrome that occurs due to chronic severe hypercalcemia where the bone starts resorbing all the calcium in the body -treat with prolonged calcitriol and Ca supplementation |
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Term
What are the clinical sings of hypocalcemia? |
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Definition
-facial pruritus -panting -seuzures 0muscle fascicualtions -hypertherma (due to m fasciculations) -myalgia -stiff gait -nervousness -GI signs: anorexia, vomiting, diarrhea |
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Term
Out of the clinical signs that occur due to hypocalcemia, which do not occur with hypercalcemia? |
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Definition
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Term
What are the common causes of hypocalcemia? |
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Definition
-primary hypoparathyroidism -eclampsie: small mom + big litter + poor nutrition -kidney disease -acute pancreatitis: common in cats -intestial dz -hypomagnesemia: causes hypoparathyroidism -hypoproteinemia: only affects protein-bound Ca -prolonged urethral obstruction: cat -phosphate enemas -ethylene glycol toxicity -massive blood transfusions: anticoagulant binds Ca |
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Term
How do we treat emergency hypocalcemia? |
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Definition
-10% calcium gluconate IV over 20 mins -monitor ECG during infusion: watch for bradycardia, VPCs, shortened Q-t interval -recheck blood Ca and redose if necessary |
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Term
Describe the physiology behind prmar hypoparathyroidism. |
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Definition
-immune mediated destruction of glands -also occurs with neck trauma or surgery |
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Term
Is primary hypoparathryoidism more common in dogs or cats? |
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Definition
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Term
What is the typical signalment of a dog with primary hypoparathyroidism? |
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Definition
-around 5y -60% female -breed: tory poodle, lab, mini Schnauzer, GSD, terriers |
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Term
What are the clinical signs in a dog with hypoparathyroidism? |
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Definition
-seizure -hyperthermia -tense abdomen -stiff gait -muscle fasciculations |
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Term
What do we see in lab data of dog with hypoparathyroidism? |
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Definition
-dec Ca and inc P -CBC and UA are normal |
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Term
How can we definitively diagnose hypoparathyroidism in a dog? |
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Definition
-dec ionized Ca and dec PTH |
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Term
How do we medically maintain hypoparathyroidism? |
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Definition
-oral calcitriol: BID -oral calcium (tums): don't need long-term if they are on a good diet |
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