Uremic tumoral calcinosis in patients receiving longterm hemodialysis therapy

Objective. To analyze a series of uremic tumoral calcinosis (UTC) in patien ts receiving longterm dialysis therapy. Methods, Twelve patients receiving longterm hemodialysis affected by tumora l calcinosis were analyzed, Clinical, radiological, and pathological featur es were evaluated and pathogenic factors were reviewed. Results, The most common sites for UTC were the elbow, hip, hand, and wrist . The lesions were multiple (67%, n = 8), of large size, and symptomatic wi th joint mobility impairment (75%, n = 9) as well as nerve compression (33% , n = 4). High serum calcium and phosphate concentrations were detected in 50% (n = 6) and 100% of the patients, respectively. An increased calcium-ph osphorus product (Ca x P) was observed in all patients, either due to overt secondary hyperparathyroidism (42%, n = 5), or secondary to iatrogenic hyp ercalcemia and/or severe hyperphosphoremia of multifactorial etiology (i.e. , prolonged and excessive administration of calcitriol and calcium carbonat e, insufficient dialysis and inadequate phosphorus chelating therapy, etc.) (58%, n = 7). Several treatment strategies were followed (surgical excisio n, parathyroidectomy, renal transplant) in combination with aggressive medi cal therapy to decrease Ca x P product, achieving complete remission in 83% of the patients. Conclusion. UTC lesions show clinical and pathogenic features that differ f rom those of idiopathic tumoral calcinosis. The most important pathogenic f actor involved in UTC is an increase in Ca x P, not necessarily related to hyperparathyroidism. Combined treatment strategies allow complete remission in a high proportion of patients. A low Ca x P is necessary to prevent dev elopment of UTC.