Calcifying and Ossifying Disorders of the Skin
Cutaneous deposition of calcium has a range of manifestations, from mild to fatal, and a number of etiologies. It is categorized as dystrophic if calcium deposits within pre-existing damaged skin, metastatic if it results from a calcium and/or phosphate imbalance, mixed if both dystrophic and metastatic factors converge, iatrogenic if due to medical intervention, and idiopathic if no cause can be determined. Osteoma cutis develops when calcium combines with phosphorus and deposits as hydroxyapatite crystals in a proteinaceous matrix. Osteoma cutis can arise in association with chronic acne and as a manifestation of several genetic disorders. Because the treatment of these conditions can be challenging, early identification and intervention are critical.
