Original StudyCutaneous Calciphylaxis A Retrospective Histopathologic EvaluationMochel, Mark C. MD*; Arakaki, Ryan Y. BA†; Wang, Guilin MS*; Kroshinsky, Daniela MD, MPH†; Hoang, Mai P. MD*Author Information Departments of *Pathology †Dermatology, Harvard Medical School and Massachusetts General Hospital, Boston, MA Reprints: Mai P. Hoang, MD, Department of Pathology, Massachusetts General Hospital, 55 Fruit Street, Warren 820, Boston, MA 02114 (e-mail: [email protected]). The authors have no funding or conflicts of interest to declare. The American Journal of Dermatopathology: July 2013 - Volume 35 - Issue 5 - p 582-586 doi: 10.1097/DAD.0b013e31827c7f5d Buy Metrics Abstract Calciphylaxis is a rare and life-threatening disease characterized by cutaneous necrosis and vascular calcification. Often, skin biopsy specimens are not diagnostic because of the limited depth of the specimen, biopsy site, and clinical stage. To better understand the utility of various histologic features in rendering the diagnosis of calciphylaxis and to compare von Kossa versus Alizarin red stains in the detection of calcium deposits, we retrospectively analyzed the histologic features and histochemical stain findings of 56 skin biopsies from 27 consecutive patients seen at Massachusetts General Hospital from October 2002 to April 2012, with confirmed diagnosis of calciphylaxis and compared with that of 19 skin biopsies from 17 patients with other disease processes. All forms of vascular calcification and vascular thrombosis were significantly associated with cutaneous calciphylaxis. Perieccrine calcium deposition, highly specific to calciphylaxis, was the only form of calcium deposition noted in 4 (7%) skin biopsies from patients with calciphylaxis. Although the staining appears to be comparable, the deposits seen on Alizarin red appeared larger and were birefringent. Although subtle, perieccrine calcification may aid in the diagnosis of calciphylaxis in settings where typical vascular and extravascular calcification are not identified. Performing both von Kossa and Alizarin red stains might increase the detection of calcium deposit. © 2013 by Lippincott Williams & Wilkins.