Author: Dr Ben Tallon, Dermatologist/Dermatopathologist, Tauranga, New Zealand, December 2016.
The deposition of calcium in the skin, subcutaneous tissue, muscles and visceral organs is known as calcinosis. This condition commonly occurs in the skin, where it is known as calcinosis cutis or cutaneous calcification.
Histology of calcinosis cutis
There are irregular deposits of intensely basophilic acellular material in the dermis and subcutaneous tissue (figure 1). The basophilia is so strong that the appearance is of a deep purple (figures 2, 3). The deposits are typically well circumscribed, with a thin rim of eosinophilichyalinisation and frequently a host giant cell reaction.
Artefactual lines form in the calcification and surrounding tissue due to shatter with cutting (figure 1).