[Calcifying panniculitis].
We report a case of calcifying panniculitis which occurred in a 67-year old woman suffering from chronic renal failure and primarily involved anticoagulant injection sites. Calcifying panniculitis is a rare condition belonging to the spectrum of calciphylaxis first described by Selye in 1962. This disease seems to imply necessarily a specific morbid background including renal failure together with calcium-phosphate metabolism impairment. Following the action of a so-called "challenger" (in the present case calcium heparinate [Calciparine], a subcutaneously administered anticoagulant drug), the lesions start as painful subcutaneous nodules soon turning into plaques of necrosis. The area involved mainly includes the abdomen and thighs, due to the preferential distribution of fat and the classical use of such regions for subcutaneous injections. In our patients, histological examination disclosed an initial involvement of subcutaneous fat vessels mimicking mediacalcosis, soon followed by calcium-phosphate deposits within interadipocyte spaces. An electron microscopy study confirmed the presence of calcium crystals within the cytoplasms of some connective tissue cells and the extracellular matrix. From a review of the literature, it seems reasonable to normalize the calcium-phosphate product by reducing hyperparathyroidism as a first therapeutic step. Then, wide surgical excision of the necrotic areas should be performed to rule out any possibility of self worsening of the lesions and provide the best chance of healing without superinfection. The use of diphosphonates on pathophysiological grounds is discussed.