CME ArticleCalciphylaxis-Associated Cutaneous Vascular Calcification in Noncalciphylaxis PatientsChaudet, Kristine M. MD*; Dutta, Puja BS†; Nigwekar, Sagar U. MD‡; Nazarian, Rosalynn M. MD§Author Information *Pathology Resident, Pathology Service, Massachusetts General Hospital, Harvard Medical School, Boston, MA; †Undergraduate Student, Carnegie Mellon University, Pittsburgh, PA; ‡Attending Nephrologist, Division of Nephrology, Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA; and §Attending Pathologist, Dermatopathology Unit, Pathology Service, Massachusetts General Hospital, Harvard Medical School, Boston, MA Correspondence: Rosalynn M. Nazarian, MD, Dermatopathology Unit, Pathology Service, Massachusetts General Hospital, 55 Fruit Street, WRN-834, Boston, MA 02114 (e-mail: email@example.com). S. U. Nigwekar is supported by National Center for Research Program Winter 2015 Fellow-to-Faculty Transition Award 15FTF25980003 from the American Heart Association and by KL2/Catalyst Medical Research Investigator Training award TR001100 (an appointed KL2 award) (S.U.N.) from Harvard Catalyst, The Harvard Clinical and Translational Science Center (National Center for Research Resources and the National Center for Advancing Translational Sciences, National Institutes of Health). The funding sources had no role in the design of this manuscript. S. U. Nigwekar and R. M. Nazarian contributed equally to this work. All authors, faculty, and staff in a position to control the content of this CME activity and their spouses/life partners (if any) have disclosed that they have no financial relationships with, or financial interests in, any commercial organizations relevant to this educational activity. The American Journal of Dermatopathology: August 2020 - Volume 42 - Issue 8 - p 557-563 doi: 10.1097/DAD.0000000000001519 Buy Take the CME Test Metrics Abstract Calciphylaxis is a highly morbid disease that is strongly associated with chronic kidney disease (CKD); however, the histologic criteria for diagnosis have not been well established nor have their specificity for calciphylaxis been determined. This retrospective study aimed to examine the prevalence of histologic features commonly associated with calciphylaxis in noncalciphylaxis patients. We also sought to evaluate whether these features may be more prevalent in patients with CKD. To assess this, healthy marginal skin tissue from above-the-knee amputation specimens was compared between patients with CKD (n = 23) and without CKD (n = 47). Intravascular calcification of capillaries or small-to-medium arterioles was detected on von Kossa stain in 40.0% of the entire cohort. Capillary calcification and intravascular thrombosis were more prevalent in patients with CKD. Finely stippled capillary calcification was present in 26.1% of patients with CKD versus 8.5% of patients without CKD (P = 0.0484), and intravascular thrombosis was present in 8.7% of patients with CKD and 0.0% of patients without CKD (P = 0.0403). None of the patients in this study had clinical evidence of calciphylaxis at presentation and in at least a 1-year follow-up period. This study confirms that the histologic features previously associated with calciphylaxis are nonspecific and are more prevalent in patients with CKD. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.