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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