Exam 5 Review Flashcards
(40 cards)
what is the most common cause of pathologic hypercalcemia?
hypercalcemia of malignancy
- humoral because it’s a hormone! apocrine gland adenocarcinoma of anal sac, lymphoma
- often related to PTH-related protein (PTH-rP)- secreted by neoplastic cells!
a dog presents with a history of PU/PD. CBC is normal, lymph nodes are normal, and a rectal exam revealed a small mass near her anal opening. what is your suspicion of her hypercalcemia on serum chemistry?
hypercalcemia of malignancy
what are clinical manifestations of hypercalcemia?
- PU/PD
- lethargy, weakness, constipation
- mineralization of soft tissue
- calcium containing uroliths
what effect does vitamin D have on Ca and P?
increases BOTH
what effect does PTH have on Ca and P?
increases calcium
decreases phosphorus
what is the major cause of hypocalcemia?
HYPOALBUMINEMIA!
40% of calcium is bound to albumin. when albumin decreases, TOTAL calcium decreases! ionized is unchanged.
most common cause of decrease in total calcium!
what abnormalities are seen with primary hyperparathyroidism?
- increased total calcium
- increased ionized calcium
- increased PTH
- decreased to normal phosphorus
- increased to normal calcitrol: PTH stimulates
- undetectable PTHrP
what causes primary hyperparathyroidism in dogs?
- solitary adenoma
- autonomously secreting PTH
- older dogs >10
what causes hyperphosphatemia?
- decreased GFR!! either from prerenal azotemia (decreased renal blood flow) or renal disease: most common cause!
what are non-GFR related causes of hyperphosphatemia?
- vitamin D intoxication
- excessive P intake
- primary hypoparathyroidism
what is a titrational acidosis?
increased organic acids: bicarb titrates acid and is used up. anion gap will be increased
what is a secretional acidosis? what disease is it associated with?
loss of bicarbonate! anion gap will be normal
addison’s disease!
how do you calculate an anion gap?
(Na + K) - (HCO3 + Cl)
what contributes to an increased anion gap? what is this called?
excess ketones, lactic acid, sulfates, phosphates, uremic acids, ethylene glycol metabolites
called a titrational acidosis
