Answer 4


A. Tumoral Calcinosis

Extraosseous calcification is more common in the secondary than in the primary form of disease. This includes tumoral calcification and renal calcification.


Secondary Hyperparathyroidism

  • Is most often associated with chronic renal failure.
  • Osseous manifestations include: subperiosteal bone resorption, intracortical bone resorption, endosteal resorption, subchondral resorption.
  • Characterized by pronounced parathyroid gland hyperplasia resulting from end-organ resistance to parathyroid hormone (PTH).
  • Hypersecretion of PTH depresses calcium levels.
  • In chronic renal failure hyperphosphatemia and damaged renal parenchyma leads to a reduction of 1-a-(OH)2 D3, or 1,25-dihydroxycholecalciferol (1,25-DHCC).
  • Intestinal absorption of vitamin D is decreased.
  • Calcium mobilization is impaired due to PTH resistance.


Resnick D, Niwayama G. Parathyroid disorders and renal osteodystrophy. In: Resnick D, eds. Diagnosis of bone and joint disorders. 3rd ed. Philadelphia, Pa: Saunders, 1995; 2014-2015.