Calciphylaxis : Population, Risk Factors, Diagnostic Practice, Therapeutic and Outcome

Calciphylaxis, also called Calcific Uremic Arteriolopathy (CUA) is a lethal affection mostly affecting patient in end stage renal disease. The survival rate is described around 20 to 46% at one year. Clinical presentation is very painful skin lesions with ulceration mostly located on the trunk or thigh. Current knowledge about physiopathology, diagnostic practice and therapeutic is very limited. Actually there is no European study about calciphylaxis and risk factors, diagnostic practice and outcome factors.

Inclusion Criteria: * patients ≥ 18 years with chronic renal failure with Glomerular Filtration Rate \< 30ml/min/1,73m² * diagnosis of calciphylaxis between 2006 and 2016 * living in the Regions of Bretagne, Pays de la Loire, Poitou-Charentes or Centre Val de Loire. Exclusion Criteria: * realized biopsy in favor of differential diagnosis * significant arterial lesion of lesion area or differential diagnosis more valid * if the diagnosis is not based on the following criteria: 3 clinical criteria or 2 clinical criteria and biopsy in favor, criteria which are : * Patient in chronic hemodialysis or stade 4 chronic kidney disease * At least 2 painful sores and hardly curable with concomitant painful purpura * Sore and purpura localisation in trunk, extremities and penis.