[Calciphylaxis: ischemic tissue necrosis in chronic renal failure. Case report and review of the literature]

Leg Ulcers of Unusual Causes

In this review, unusual causes of leg ulcers are examined with an emphasis on pathophysiology, clinical presentation, and epidemiology. Cutaneous ulcers due to malignancy of unusual leg ulcers with hematologic disorders, vasculitis, sarcoidosis, calciphylaxis, Buerger’s disease, and pyoderma gangrenosumare discussed.

[Vascular emergencies in dermatology]

Life-threatening vascular complications of the skin are rare and usually reflect underlying systemic diseases. Lesions are sudden in onset, become necrotic and may be severe or life-threatening. Effective management requires an understanding of the underlying medical condition, such as arterial thrombosis, temporal arteritis, calciphylaxis and purpura fulminans. In contrast, the acute painful symptoms of erythromelalgia often lead to an urgent dermatologic consultation but pose no acute risk.

Spotting the signs: a case of late diagnosed painful calciphylaxis

Although the number of cases of calciphylaxis is increasing, it is often not diagnosed until a late stage, increasing the risk of mortality. A characteristic is purple, mottled and painful lesions, which have a tendency to become necrotic.

Tumoral calcinosis revisited: pathophysiology and treatment

In two renal failure patients, tumoral calcinoses were observed as a result of secondary hyperparathyroidism. The primary conservative therapy conducted with dietetic measures and phosphate-binding medication could not prevent the progression of the massive polytopic foci. Therefore, a subtotal parathyroidectomy was performed in one case, after which a rapid complete regression of the tumours was observed, with the exception of one location where the finding remained progressive. The second patient declined surgical intervention on the parathyroid gland. Therefore, the foci were only resected, whereby local recurrences were observed. Renal failure patients with tumoral calcinosis should undergo subtotal parathyroidectomy after initial conservative therapy. In view of the high risk of recurrence, local excision is a treatment procedure to be considered in exceptional cases only.

[Dialysis associated skin changes]

Patients with end-stage renal disease often suffer from different dermatologic conditions. Reports indicate that 50-100% of patients with end-stage renal disease have at least one cutaneous disorder. The persisting chronic uremia is responsible for a variety of structural and functional skin changes. Dialysis or even renal transplantation leads to an improvement of some uremia associated skin disorders, others however can persist.

Cellular component of vascular calcification. Fibroblasts are essential for calcium deposition in cultured cells

It has been reported that calcium deposition and calcium content in cultured human aortic smooth muscle cells (SMC) increased when the cells are incubated in a medium with a high phosphate concentration (2 mM). To determine the cellular components or soluble factors contributing to the deposition, we cultured commercially available SMC, fibroblasts (Fb) and endothelial cells (Ed). These cells and their mixtures were incubated for 10 days in normal or high-phosphate media. Calcium crystals were stained by the von-Kossa staining and counted in the defined area. Calcium content was measured by a colorimetric assay. SMC were incubated in high-phosphate media (up to 2 mM) or beta-glycerophosphate (beta-GP) media, resulting in no obvious deposition of calcium crystals, irrespective of the coating of type I collagen on the dish. Next, various combinations of cells were cultured, and a significant number of depositions were observed only when Fb were included in the combination. The calcium content was significantly higher in cultures of SMC and Fb. The calcium deposition on single or mixture of the cells did not increase compared with control when cells were incubated in a high concentration of phosphate, cultured in the existence of beta-GP or uremic serum. We therefore conclude that Fb, rather than SMC or Ed, are essential for calcium deposition and calcium accumulation in culture. Phosphate concentration in the medium and uremic serum did not influence the deposition of calcium.