Calcium may preferentially deposit in areas of elastic tissue damage

Background Cutaneous calcification is an acquired disorder whereby insoluble, amorphous calcium salts deposit in the skin. Classically, cutaneous calcification is categorized as metastatic, dystrophic, idiopathic, or iatrogenic. Objective The purpose of this study was to further elucidate the underlying pathogenic mechanism for cutaneous calcification. Methods Three cases of cutaneous calcification, including clinical characteristics and associated histopathology, were reviewed. Previous reports of cutaneous calcification were searched for in the published literature and included. Results Calcium is distributed within areas of underlying tissue damage (ie, locus minoris resistentiae), and in our cases, occurred specifically at sites of chronic actinic damage and intravenous extravasation tissue injury. Limitations A small number of clinical cases and previously published reports were reviewed. Conclusion We hypothesize that cutaneous calcification may preferentially occur at anatomic sites where tissue integrity has been compromised (ie, locus minoris resistentiae). We suggest one potential mechanism: that cutaneous calcification occurs within dermis that contains damaged elastic fibers. Pseudoxanthoma elasticum may serve as a possible genetic disease model for this process.