Parathyroid Pathology Flashcards
What are the 3 predominant cell types present in the parathyroid glands?
Chief cells, oxyphil cells and adipocytes
What are the characteristics of chief cells?
Central round and uniform nuclei, light pink/white cytoplasm, secretory granules
What are the characteristics of oxyphil cells?
Smaller, darker nuclei; eosinophilic granular material (mitochondria), less endocrinologically active
What is the principle function of the parathyroid gland?
Ca homeostasis
What are the effects of PTH?
Directly releases Ca from bone; Ca resorption from the kidney, blocks phosphate resorption, converts 25(OH)d to 1,25(OH)2D in the kidney (further mobilizes Ca from bone and intestine)
How does the parathyroid gland know what to do?
The CaSR regulates the amount of PTH secreted from the parathyroid glands
Low serum Ca results in what?
Increased PTH secretion
High serum Ca results in what?
PTH suppression
What are non-parathyroid related causes of hypercalcemia with low PTH?
Malignancy (hypercalcemia of malignancy), vitamin D excess (granulomatous dz, hypervitaminosis), excess Ca ingestion, meds (thiazide diuretics)
What are the minor sx of hypocalcemia?
Numbness or tingling of fingers, muscle cramps, poor appetite, weak or brittle fingernails, difficulty swallowing, fainting or lethargy
What are the severe sx of Hypocalcemia?
Mental confusion, irritability, depression, anxiety, tooth erosion, insufficient blood clotting, bone fractures, osteopenia or osteoporosis, growth and development delays in children, heart problems involving BP and heart rhythms
What is the Chvostek’s sign?
a twitch of the facial muscles that occurs when gently tapping an individual’s cheek in front of the ear; sign of hypocalcemia
What is Trousseau’s sign of hypocalcemia?
Spasm of hand and wrist upon BP cuff inflation
If PTH levels are high and urinary Ca excretion levels are high what does this indicate?’
Primary and tertiary hyperparathyroidism
