Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
34 Cards in this Set
- Front
- Back
What is the embryonic derivation of the superior parathyroid glands?
|
4th pouch
|
|
What is the embryonic derivation of the inferior parathyroid glands?
|
3rd pouch
|
|
most common ectopic site for parathyroid gland
|
tail of the thymus
|
|
blood supply to both superior and inferior parathyroid glands
|
Inferior thyroid artery
|
|
increases serum calcium
increases kidney Ca reabsorption in the distal convoluted tubule, increases OSTEOCLAST, increase Vit D in the kidney |
PTH
|
|
Increases intestinal Ca and P04 absorption by increasing calcium-binding protein
|
Vitamin D
|
|
decrease serum Ca
|
Calcitonin
by osteoclast inhibition increased urinary excretion of Ca and PO4 |
|
name the disease.
Women, older age • Due to autonomously high PTH • Dx: increased Ca, decreased phosphorus; Cl- to phosphorus ratio > 33, increased renal cAMP, HC03- secreted in urine • Can get hyperchloremic metabolic acidosis • Osteitis fibrosa cystica (brown tumors) - bone lesions from Ca resorption |
PRIMARY HYPERPARATHYROIDISM
|
|
Indications for surgery with PRIMARY HYPERPARATHYROIDISM
|
symptomatic disease or asymptomatic disease with
Ca > 13 decreased Cr clearance, kidney stones, substantial loss of bone mass |
|
Tx for Parathyroid CA
|
radical parathyroidectomy ( need to take ipsilateral
thyroid ) |
|
Tx for Parathyroid Adenoma
|
resection; inspect other glands to rule out hyperplasia or multiple adenomas
|
|
tx of Parathyroid hyperplasia
|
Do not biopsy all glands 2/2 risks hemorrhage and hypoparathyroidism
• Resect 3.5 glands or total parathyroidectomy and auto implantation |
|
What is the 1/2 life of PTH?
|
10 min
|
|
most common ectopic location
of parathyroid gland. |
thymus
|
|
what most commonly causes Persistent hyperparathyroidism (1 %)
|
missed adenoma
remaining in the neck |
|
Will have preferential uptake by the overactive parathyroid gland
• Good for picking up adenomas but not 4-gland hyperplasia • Best for trying to pick up ectopic glands |
Sestamibi-technetium-99
|
|
Seen in patients with renal failure
• increased PTH in response to low Ca Most do not need surgery ( 90%) • Ectopic calcification and osteoporosis can occur |
SECONDARY HYPERPARATHYROIDISM
|
|
Tx of SECONDARY HYPERPARATHYROIDISM
|
control diet P04
sx indicated with bone pain |
|
• Renal disease now corrected with transplant but still overproduces PTH
• Has similar lab values as primary hyperparathyroidism (hyperplasia) • Tx: subtotal ( 3.5 glands) or total parathyroidectomy with autoimplantation |
TERTIARY HYPERPARATHYROIDISM
|
|
Patients have increased serum Ca and decreased urine CA (should be increased if hyperparathyroidism)
• Caused by defect in PTH receptor in distal convoluted tubule of the kidney that causes increased resorption of Ca • Dx: Ca 9-11, normal PTH (30-60), decreased urine Ca • Tx: nothing (Ca generally not that high in these patients); |
FAMILIAL HYPERCALCEMIC HYPOCALCIURIA
|
|
defect in PTH receptor in the kidney, does not respond to PTH
|
PSEUDO HYPOPARATHYROI DISM
|
|
Rare cause of hypercalcemia
• 50% 5-year survival rate • Mortality is due to hypercalcemia increased Ca, PTH, and alkaline phosphatase (can have extremely high Ca levels) • Lung most common location for metastases • Tx: wide enbloc excision (parathyroidectomy and ipsilateral thyroidectomy) • Recurrence in 50% |
PARATHYROID CANCER
|
|
Describe MEN I
|
1. Parathyroid hyperplasia
2. Pancreatic islet cell tumors 3. Pituitary adenoma |
|
Describe MEN IIa
|
1. Parathyroid hyperplasia
2. Pheochromocytoma 3. Medullary CA of thyroid |
|
Describe MEN lIb
|
1. Pheochromocytoma
2. Medullary CA of thyroid 3. Mucosal neuromas 4. Marfan's habitus, musculoskeletal abnormalities |
|
• Parathyroid hyperplasia
-Usually the first part to become symptomatic; urinary symptoms, Tx: 4-gland resection with autotransplantation • Pancreatic islet cell tumors - Gastrinoma #1, 50% multiple, 50% malignant major morbidity of syndrome • Pituitary adenoma - Prolactinoma #1 • Need to correct hyperparathyroidism 1 st |
MEN I
|
|
• Parathyroid hyperplasia
• Pheochromocytoma - Very often bIlateral, nearly always benign • Medullary CA of thyroid - Nearly all patients; diarrhea most common symptom; often· bilateral - #1 cause of death - Usually 1st part to be symptomatic • Need to correct pheochromocytoma 1st |
MEN lla
|
|
• Pheochromocytoma
-Very often bilateral, nearly always benign • Medullary CA of thyroid - #1 cause of death in these patients • Usually 1st part to be symptomatic • Mucosal neuromas • Marfan's habitus, musculoskeletal abnormalities • Need to correct pheochromocytoma 1st |
MEN IIb
|
|
Gene causing MEN I
|
MENIN gene
|
|
Gene causing MEN II
|
RET proto-oncogene
|
|
Drug that inhibits osteoclasts (used with malignancies or failure of conventional
treatment); has hematologic, liver, and renal side effects |
Mithramycin
|
|
Tx of Hypercalcemic crisis
|
usually secondary to another surgery
Tx: fluids, furosemide, dialysis |
|
release PTHrp; can cause hypercalcemia
|
Breast CA metastases to bone
Small cell lung CA this is not due to bone destruction Associated with increased urinary cAMP (from action of PTHrp on kidney) |
|
malignancy that cause bone destruction; can also increase Ca and urinary cAM P will below
|
Hematologic malignancies
|