Clinical characteristics of 10 patients with uremic tumoral calcinosis

Objective: To analyze the clinical characteristics of patients with uremic tumoral calcinosis (UTC). Methods: A total of 10 patients with UTC were enrolled in this study, who were admitted in the Department of Nephrology, China-Japan Friendship Hospital and Beijing Chuiyangliu Hospital from March 2013 to February 2019. Results: The average age of 4 male and 6 female patients on regular hemodialysis was (39.90±8.57) years. The average dialysis duration was(5.90±2.57) years. Three patients presented as single lesion of one joint, the other 7 patients as involvement of multiple large joints. Serum calcium was elevated in 2 patients,both over 2.75 mmol/L. Serum hyperphosphatemia was seen in all patients with average level 2.22 (1.94,2.44) mmol/L. Serum intact parathyroid hormone (iPTH) was remarkably increased in 9 patients with average level 1 348.0(854.8,1 800.0) ng/L, while only 1 patient reported slight elevation (92.4 ng/L).High-sensitivity C-reactive protein increased in all 10 patients with average 35.81 (17.60,74.20) mg/L. The imaging findings before treatment suggested that a large number of irregular masses of calcification shadows deposited in the soft tissue adjacent to the joints. The outlines of calcification were clear without significant bone absorption. Nine patients with severe secondary hyperparathyroidism (SHPT) were treated with parathyroidectomy, resulting in lesions diminishing or even disappearing. A total of 32 parathyroid glands were resected, and pathological results showed that 7 parathyroids were diffuse hyperplasia, 11 as diffuse/nodular hyperplasia, the rest 14 as nodular hyperplasia. At least one hyperplastic parathyroid gland was seen in each patient. Only 1 patient received medical therapy yet no obvious improvement was observed. Conclusion: UTC is a rare complication in patients on regular hemodialysis, which is usually associated with severe SHPT. Parathyroid surgery may improve the clinical outcome.