Foreword: extraskeletal calcifications in patients with chronic renal failure.

Abstract

In recent years, increasing interest has been devoted to soft-tissue calcification in patients with chronic renal failure. Although it has been known for many years as a frequent complication of this condition, its high prevalence and prominent role in cardiovascular morbidity and mortality of uraemic patients have only been recognized recently. There are several explanations for the greater prevalence of extraosseous calcifications in the last decade w1x. They include the steadily increasing age of the chronic dialysis population, the progressive improvement of survival for each age group with a prolonged exposition to factors predisposing to soft-tissue calcification, an uncontrolled serum calcium 3 phosphate (Ca 3 P) product in a large portion of end-stage renal disease patients and, last but not least, an improvement in the objective, quantified assessment of calcium deposits. The type, distribution, speed of progression and severity of extraskeletal calcifications vary widely from patient to patient, and also from centre to centre, depending on numerous factors in addition to the uraemic milieu w1x. Periarticular and vascular calcifications, also called non-visceral calcifications, are morphologically and pathogenetically distinct from visceral calcifications. Similarly, dystrophic calcium deposits differ from metastatic deposits. Such distinctions need to be made for the understanding of underlying mechanisms and the identification of appropriate therapeutic and prophylactic measures. Another important consideration is that soft-tissue