General Considerations

•calcinosis circumscripta is reported in cats and dogs

•deposition of calcium in areas other than bone or teeth is pathologic and termed either dystrophic, metastatic, idiopathic, or iatrogenic

•dystrophic calcification: deposition of calcium salts within dead or degenerative tissue and is unrelated to calcium content of blood

•metastatic calcification: precipitation of calcium salts within tissue because of derangements in metabolism of calcium, phosphorus, or both (i.e., primary, secondary, and pseudohyperparathyroidism, chronic renal failure, and hypervitaminosis D)

•calcium deposited as calcium phosphate, calcium carbonate, or as hydroxyapatite

•calcium circumscripta definition: local ectopic deposition of calcium salts usually in subcutaneous tissue

•cause unknown although associated with trauma, injections, and previous surgery

•calcinosis cutis has been secondary to intramuscular injection of calcium gluconate for the management of primary hypoparathyroidism

•gross appearance: ≥ 1 small, well-circumscribed subcutaneous mass

•other sites: tongue, salivary gland, spine, and aorta