LAUSR

We read with great interest the recent article by Musso et al. about the differential diagnosis of calciphylaxis [1]. We would like to discuss recent developments in diagnosing calciphylaxis. Recently, nephrologists are moving away from invasive ways to diagnose calciphylaxis because of the associated complications. However, the differentials of any chronic wound ulcer in an ESRD patient is so varied, that even “clinical pearls” might not be enough to help us. One excellent “microscopic pearl” which we would like to mention is pseudoxanthoma elasticum-like changes (PXE) which basically are changes in elastic fibers detected with elastic and von Kossa stains [2]. Chen at el studied association between PXE-like changes and calciphylaxis, and found that finding PXE-like changes on suboptimal skin biopsies who lack microvascular calcification could potentially hint towards calciphylaxis [2]. Not to forget about the exceptional cases where dual diseases coexist and that requires multimodality approach and treatment [3, 4]. We agree with Musso et al. mentioning about developing a scoring system just like any other scoring system to give us the probability of having calciphylaxis before we do a skin biopsy (e.g. Well’s criteria for pulmonary thromboembolism). Herein, we would also like to mention about the recently studied non-invasive techniques which might be helpful for diagnosing calciphylaxis [5–7]. Hybird/PET scan has been found as an excellent modality in calciphylaxis, but data are immature to comment about its dependability in addition to being an expensive test. PET scan is gaining interest at a rapid pace, thanks to its capability to detect idolent and hidden disease activity [8, 9]. The two major world authorities working actively on calciphylaxis are European Calciphylaxis Network (EuCalNet) and Partners Calciphylaxis Biobank (PCB). We believe that pooling the data from such organizations would help us in formulating a scoring system which could potentially be helpful in avoiding unnecessary skin biopsies or justifying skin biopsies in relevant cases [6, 7].