Lecture 5 - Parathyroid/calcium disorders Flashcards
PTH is released in response to low serum ____ or high serum ____
calcium, phosphate
PTH:
increases reabs of calcium in the _____;
increases secretion of phosphate in the _____;
increases production of Vit D by stimulating ____ in the _____;
increases bone resorption of ….
DCT;
PCT;
1 alpha hydroxylase, PCT;
Ca and PO4
calcitriol causes increased release of ____ which decreases bone formation.
calcitriol also increases calcium and phosphate reabsorption from the ____ and _____
FGF23;
GI, kidney
calcium:
increase in concentration causes a _____ in refractoriness of stimulation of neurons and muscle cells
increase
causing coma, muscular weakness
decrease in calcium leads to _____ in neuromuscular excitability–>translates into _____ and ____
increase;
tetany, convulsions
what is the name of the calcium salt that is the major structural cation?
hydroxyapatite
calcium:
alkalosis causes a _____ in binding affinity to albumin, ____ calcium levels and causing _____
increase;
lowering;
tetany, parasthesia
calcium levels also decrease with decreased levels of serum ____ or increased levels of ____
albumin, phosphate
hypocalcemia: \_\_\_\_; chvostek sign = trousseau sign = in the heart: \_\_\_\_\_\_
tetany;
tap facial nerve–>contract muscle;
occlude brachial artery–>carpal spasm;
prolonged QT (risk of torsades)
hypoparathyroidism: during ____ surgery, autoimmune destruction, ____ syndrome
thyroid;
digeorge
digeorge syndrome:
CATCH 22
C = cleft palate A = abnormal facies T = thymic aplasia --> T cell deficiency C = cardiac defects H = hypo calcemia
22q11 deletion
according to FA, normal serum calcium is between ____ and ____
8.4-10.2 mg/dL
hypercalcemia symtpoms:
_____, ____, _____, _____, and ____ overtones
stones (nephrolithiaisis) bones (bone pain) groans (abdominal pain, constipation) thrones (increased urinary frequency) psychiatric (anxiety, impaired concentration)
primary hyperparathyroidism:
usually due to ___ or ____;
in addition to the hypercalcemia symptoms mentioned, can have acute ____, ______ ulcers, nephrocalcinosis
adenoma, hyperplasia;
pancreatitis;
peptic
familial hypocalciuric hypercalcemia:
due to defective ______ in multiple tissues. ____ than normal Calcium is required to suppress PTH =
mild ____ and hypo _____ with ____ PTH levels
Ca sensing receptors;
greater;
hypercalcemia, hypocalcuria;
normal to increased
diuretics:
_____ diuretics decrease reabsorption –> hypocalcemia;
_____ diuretics increase reabsorption
loop;
thiazide
hypercalcemia of malignancy can be due to ____ or _____
bony metastases;
PTHrp
after confirming clinical hypercalcemia, what should you check next?
intact PTH ( if increased, primary HPTH or familial)
with chronic renal failure:
___calcemia, ____phosphatemia, failure of _____ –> __ PTH levels
hypo, hyper;
vitamin D hydroxylation;
increased
criteria for surgery of primary hyperPTH: clinical manifestations of \_\_. age \_\_\_ than 50 years; creastinine clearance less than \_\_\_\_ current or past kidney \_\_\_
hypercalcemia;
less than;
60;
stones
Vitamin D deficiency causes a ____ in urinary phosphate excretion
increase
symptoms of hypophosphatemia:
bone ____, ____ levels fall causing an increase in Hb affinity = tissue ____;
encepalopathy, rhabdomyolysis
loss;
2,3 DPG;
hypoxia
hyperphosphatemia:
renal ____, metastatic _____, ___calcemia
asociated with tumor lysis, rhabdomyolysis
hypo PTH
stones, calcification, hypo
osteomalacia:
decreased VIT D –> ____ serum Ca –> ___ PTH –> ____ serum PO4
____ ALP
decreased, increased, decreased;
increased
rickets symptoms: genu \_\_\_\_ (bow legs), bead-like \_\_\_\_\_\_\_ (rachitic rosary), \_\_\_\_\_ (Soft skull), frontal bossing
varum;
costochondral junction;
craniotabes
_____ are characteristic radiological findings in osteomalacia. they are ____ of femoral neck/nearby areas
looser’s zones;
pseudofractures
chronic kidney disease:
see ____ Ca absorption and/or ____ phosphate absorption . renal failure causes decreased ____ levels –> excessive levels of _____
decreased, increased;
vitamin D;
PTH (secondary HPTH)
______ is due to high bone turnover caused by hypert PTH. causes ____ bone spaces
osteitis fibrosa cystica;
cystic
what is tertiary hyper PTH?
autonomous/refractory hyper PTH resulting from CKD.
3 stages of paget disease:
osteoclastic overactivation (lytic) mixed osteoblasts and osteoclasts osteoblast overactivation (sclerotic)
paget's: localized or widespread bone disorder? associated with increased \_\_\_\_\_ size. \_\_\_\_ loss from foramen narrowing. \_\_\_\_ ALP
localized;
hat;
hearing;
increased
serum Vit D levels should be greater than ___ ng/mL
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