Term
| origin of sup vs inf parathyroids? |
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Definition
Sup = 4th pouch (a/w thyroid complex)
Inf = 3rd pouch (a/w thymus) |
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Term
| Normal location of sup vs inf parathyroids? |
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Definition
Sup = post surface, superior part of thyroid, LAT to RLN
-above inf thyroid art
-migrate to posterior mediastinum
Inf = Medial to RLN, more anterior location. MORE VARIABLE
-migrate to anterior mediastinum |
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Term
| MC ectopic site for inf parathy? |
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Definition
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Term
|
Definition
| inferior thyroid artery for both sup and inf parathyroids |
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Term
| % of pop that has 4 parathyroids? |
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Definition
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Term
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Definition
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Term
| how does PTH increase Calcium? |
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Definition
1. Renal Ca reabsorption in distal tubules (cAMP mediated)
2. Osteoclast release of Ca
3. Renal Vit D production (inc 1-alpha OHylation of Vit D) |
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Term
| Vit D synthesis pathway = |
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Definition
1. 7-dehydrocholesterol + UV light = Vit D3
2. 25-hydroxylation @ liver = Vit D3-25OH
3. 1-hydroxylation @ kidney = Vit D |
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Term
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Definition
| Inc intestinal Ca and Phos absoprtion by increasing Ca-binding protein |
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Term
|
Definition
1. Bone Ca resorption (osteoClast inhibition)
2. Renal Ca and PO4 excretion |
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Term
Normal PTH level?
normal parathyroid weight? |
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Definition
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Term
| MC cause of hypercalcemia related to malig? |
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Definition
PTH-rp (Small cell lung = greatest risk)
only 25% of cases are from osteolysis (MMyeloma) |
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Term
| Gene associated wtih parathyroid adenoma? |
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Definition
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Term
| MC pres of primary hyperpara? |
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Definition
asymptomatic (inc Ca on routine labs)
-can have HTN from renal impairment |
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Term
| lab findings in primary hyperpara? |
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Definition
inc PTH, inc Ca + inc urine cAMP and Ca
dec phos
inc Chloride::Phos ratio > 33 (hyperchlor metabolic acidosis) |
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Term
Familial hypercalcemic hypocalciuria
cause |
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Definition
inc binding of PTH to renal PTH receptor (defect in PTH receptor)
-normal/slightly elevated PTH
-inc serum Ca, asymptomatic,
-low urine Ca->NO PARATHYROIDECTOMY IN THESE PTS |
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Term
| Primary hyperpara causes and %ages? |
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Definition
single adenoma = 80%
diffuse hyperplasia = 15% (MEN 1 or 2a)
multiple adenomas (5%)
primary adenoCA (<1%) |
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Term
| indications for surgery with asymptomatic primary hyperpara? |
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Definition
Ca > 13, or 24 hr Urine Ca > 400
Dec Cr clearance
Dec bone mass (t score -2.5)
age < 50 (dec lifetime risk of problems with Calcium etc)
pt preference |
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Term
|
Definition
resection
inspect other glands
INTRA-OP FROZEN SECTION confirm its parathryoid tissu |
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Term
| parathyroid hyperplasia tx? |
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Definition
Resect 3.5 glands (1/2 gland first)
..OR total parathyroid w/auto-implant
-dont bx all 4 glands (hemorrhage/hypopara risk) |
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Term
|
Definition
| radial parathyroidectomy -->take ipsilateral thyroid |
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Term
| timing of pregnant pt with parathryoid surgery> |
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Definition
| 2nd trimester (inc still birth if later) |
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Term
| How to confirm parathyroid tissue resection? |
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Definition
Intra-op frozen section
Intra-op PTH (level should go to 50% of pre-op value in 10 min, if abn gland was removed) |
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Term
| MC location of previously missing parathyroid gland at re-operation? |
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Definition
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Term
| Common missing gland locations? |
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Definition
-Thymus tissue = MC ectopic location for parathyroid
-anterior to vertebral bodies
-sup and post to laryn
-TE groove
-intra-thyroid |
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Term
| Surgical option if you can't find parathyroid intra-op? |
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Definition
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Term
| What to do if you fine 3 large hyperplastic parathyroids with missing 4th gland? |
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Definition
take 2.5 or 3 with auto-implant
..if still no appropriate PTH decrease-->close and get sestamibi |
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Term
| What to do if you find 3 normal sized parathyroids and can't find the adenoma? |
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Definition
check common missing spots..+/- thymectomy
still can't find it-->ipsilat thyroidectomy
STILL cant ==>close, sestamibi |
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Term
| Post-op labs patterns after parathyroid surgery? |
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Definition
-bone hunger (early) = normal PTH, dec Bicarb
-Graft/Remnant failure = dec PTH, normal bicarb
-Hypo mag |
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Term
|
Definition
occurs early
normal PTH dec Bicarb |
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Term
| % with persistent post-op hyperpara> |
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Definition
1%
MCC missed adenoma
get sestamibi |
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Term
| Causes of NEW hyper-para after period of normo/hypoCalcemia post-op? |
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Definition
-new adenoma
-tumor implant growth
-recurrent parathy Ca |
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Term
|
Definition
inc rec lary injury
inc risk perm hypoparathyroidism |
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Term
secondary hyperparathyroidism
MCC |
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Definition
|
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Term
secondary hyperparathyroidism
dx/labs |
|
Definition
-Inc PTH, dec serum Ca (or near normal)
-Inc urine Ca
-Inc serum Phos |
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|
Term
secondary hyperparathyroidism
-pathophys |
|
Definition
1. Low Ca:
dec reabsorption due to kidney failure
dec vit D (dec renal 1-OHylation) = dec Ca+ binding protein
2. Inc PTH = response to low Ca
3. Inc Phos (failed kidneys dont excrete it)
--->insoluble CaPhos = ectopic calcifications |
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Term
| MC indications for surgery vs secondary hyperparathyroidism |
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Definition
Refractory bone pain (MC indication) = 85% get relief of sxs
Refractory pruritis = 85% relief
Fractures |
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Term
secondary hyperparathyroidism
tx |
|
Definition
dietary control of Phos
Phos binder (Ca-acetate = phoslo, Ca-carbonate = tums)
Ca and Vit D sup
Cinacalet (activates Ca receptor @ parathy = dec PTH)
Surgery (only 5% need it) |
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Term
|
Definition
@ secondary hyperparathyroidism
@ parathyroid Ca with mets
= Ca mimic that activates parathyroid Ca receptor = dec PTH |
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Term
Renal osteodystrophy
-definition
-tx |
|
Definition
= defective bone mineralization 2/2 chronic 2ndary hyperparathy
-->osteopenia, chondrocalcinosis
Tx = HD, Ca/VitD sup, Phos restriction/binders, Cinacalcet |
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Term
Calciphylaxis
-def
-presentation / dx |
|
Definition
= calcific, uremic arteriopathy
-a/w chronic renal failure -->Ca-fication and thrombosis of small + medium vessels
-first manifestation = skin ischemia/necrosis
-dx = skin bx |
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Term
|
Definition
HD
Wound care
Keep Ca/phos low (goal: Ca x Phos <55)
-non-calcium containing PHos binder
-NaThiosulfate (increases Ca solubility)
poor prog |
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Term
| Tertiary hyperpara definition? |
|
Definition
Renal DZ corrected with kidney TXP
-->but still have PTH overproduction (same lab values as primary hyperpara = inc PTH and Ca) |
|
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Term
Familial hyperacalcemic hypocalciuria (FHH)
-labs
-pphys |
|
Definition
-High serum Ca (9-11) low urine Ca, normal PTH
-defect in DCT PTH receptor = INC resorption of Ca
-Tx = nothing (Ca not very high) |
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Term
|
Definition
| total parathyroid vs 3.5 and auto-implant |
|
|
Term
Pseudo-hypo-parathyroidism
-Labs/pphys
-assoc condition
-tx |
|
Definition
-Low serum Ca w/ high phos, high PTH
-Defective PTH receptor @ DTC = DEC ca reab (GPCR problem)
-a/w Albright Hereditary Osteodystrophy (round face, short 4th and 5th metacarpals)
-Tx w/ Ca |
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Term
| MCC mortality from parathyroid CA? |
|
Definition
hyper Ca (levels often >13-15)
-labs = inc Ca, PTH, alk phos |
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Term
| MC met location for parathy CA |
|
Definition
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Term
| Surgery tx for parathyroid Ca |
|
Definition
wide en block excision (parathyroidectomy and ipsi thyroidectomy
-50% recurrence
-50% 5YSR |
|
|
Term
HyperCa crisis
-lab levels?
-MCC
sx |
|
Definition
Ca > 13 (iCal > 6) w/sxs (lethargy, oliguria, hypoTN, arrhyth)
MCC = hx primary hyperpara undergoing another procedure
-MC malig cause = breast CA |
|
|
Term
|
Definition
-Rapid vol infusion (200-300 cc/hr NS==>NO LR!!!
-Lasix (NO THIAZIDES..theyr etain Ca)
-HD if refractory |
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Term
Hyper Ca crisis
-tx if 2/2 malig |
|
Definition
MC malig = breast
-Bisphos (alendronate (fosamax)) = inhib Oclasts
-Calcitonin
-Glucocorticoids
-Mithramycin (Oclast inhib)->SE = liver, renal, hematologic |
|
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Term
| what meds are contraindicated with hyperCa crisis? |
|
Definition
LR (contains Calcium)
Thiazides (retain Ca)
*USE NS AND LASI* |
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Term
|
Definition
perioral tingling
-chvostek = twitch w/face tap
-Trousseau = carpopedal spasm w/BP cuff
hyper-reflexia, Prolonged QT |
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|
Term
MEN syndromes
-cell origin
-Inheritance pattern |
|
Definition
-from APUD cells
-AD w/100% penetrance, variable expressivity |
|
|
Term
|
Definition
= MENIN inactivation (tumor supressor)==>3Ps
-parathy hyperplasia (first part to manifest with sx (stones))
-pancreatic islet cell tumors (MC gastrinoma)
-pituitary adenoma |
|
|
Term
|
Definition
Gastrinoma (50% multiple, 50% malignant)
-MCC death in MEN 1 pts |
|
|
Term
|
Definition
panc islet cell tumors
-MCC = gastrinoma ->50% multiple, 50% malignant
-also MCC morbidity |
|
|
Term
MEN 1 pt with simultaneous tumors
-what to do first? |
|
Definition
correct hyperparathyroid first
-parathy hyperplasia |
|
|
Term
|
Definition
RET proto-oncogene
-Parathyroid hyperplasia
-Medullar thyroid Ca
-Pheochromocytoma |
|
|
Term
|
Definition
RET proto-oncogene
-Medullary thyroid CA
-Pheo
-Mucosal ganglioneuromas
-Marfan habitus, MSK abn |
|
|
Term
Men 2b with simultaneous tumors
-what to do first? |
|
Definition
|
|
Term
|
Definition
BOTH = medullary thyroid Ca, pheochromo
2a = parathyroid hyperplasia
2b = marfans habitus, mucosal ganglioneuroma, MSK abn |
|
|
Term
MEN 2a
first to be sx?
MCC death |
|
Definition
Med thy Ca = first to be sx (MC with diarrhea)-
-->MCC death |
|
|
Term
MEN 2
-which has most aggressive thyroid CA? |
|
Definition
| Men 2a has more aggressive medullary thyroid Ca |
|
|
Term
| Treatment of MEN associated parathyroid hyperplasia? |
|
Definition
MEN 1, MEN 2a
-4 gland parathyroidectomy w/forearm auto-implant
-->don't leave in neck |
|
|
Term
| Pheo presentation pattern in MEN syndrome? |
|
Definition
often bilateral
almost always benign |
|
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Term
| What condition to correct first wtih MEN syndromes? |
|
Definition
MEN 1 = hyperparathyroidism (2/2 hyperplasia)
MEN 2 = pheo first (often bilat, usually benign) |
|
|
Term
| MC pituitary tumor in MEN? |
|
Definition
prolactinoma
MEN 1 (3Ps, pituitary, parathy hyperplasia, panc islet cell (gastrinoma) |
|
|
Term
| % of MEN pts that get medullary thyroid Ca? |
|
Definition
MEN 2a and 2b
-95%
*is MCC death in these pts* |
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