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EndocrinE ` endocrine—PAthology EndocrinE ` endocrine—PAthology SEcTion iii 345
Hyperparathyroidism
Primary Usually due to parathyroid adenoma or Osteitis fibrosa cystica—cystic bone spaces
hyperparathyroidism hyperplasia. Hypercalcemia, hypercalciuria filled with brown fibrous tissue A (“brown
(renal stones), polyuria (thrones), tumor” consisting of osteoclasts and deposited
A
hypophosphatemia, PTH, ALP, urinary hemosiderin from hemorrhages; causes
cAMP. Most often asymptomatic. May present bone pain). Due to PTH, classically
with bone pain, weakness, constipation associated with 1° (but also seen with 2°)
(“groans”), abdominal/flank pain (kidney hyperparathyroidism.
stones, acute pancreatitis), neuropsychiatric “Stones, thrones, bones, groans, and
disturbances (“psychiatric overtones”). psychiatric overtones.”
2+
Secondary 2° hyperplasia due to Ca absorption Renal osteodystrophy—renal disease 2° and
3−
hyperparathyroidism and/or PO 4 , most often in chronic 3° hyperparathyroidism bone lesions.
kidney disease (causes hypovitaminosis D
2+
and hyperphosphatemia Ca ).
Hypocalcemia, hyperphosphatemia in
chronic kidney disease (vs hypophosphatemia
with most other causes), ALP, PTH.
Tertiary Refractory (autonomous) hyperparathyroidism
hyperparathyroidism resulting from chronic kidney disease.
2+
PTH, Ca .
2+
Familial hypocalciuric Defective G-coupled Ca -sensing receptors in multiple tissues (eg, parathyroids, kidneys). Higher
hypercalcemia than normal Ca levels required to suppress PTH. Excessive renal Ca reabsorption mild
2+
2+
hypercalcemia and hypocalciuria with normal to PTH levels.
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