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Updated: Aug 25, 2026

A Semi-Automated and Reproducible Biological-Based Method to Quantify Calcium Deposition In Vitro
Published on: June 2, 2022
Intracranial calcification and tumoural calcinosis during vitamin D therapy
Nurhan Seyahi1, Suheyla Apaydin, Muzaffer Sariyar
1Department of Nephrology, Istanbul University, Cerrahpasa Medical Faculty, Istanbul, Turkey. nseyahi@superonline.com
Abstract:
Extraskeletal calcifications are frequently observed in patients with chronic renal failure. However, clinically, they usually remain silent. In this report, we describe two patients with massive extraskeletal calcifications that caused significant morbidity. The first patient had tumoural calcification located on the shoulder and the second patient had severe neurological symptoms caused by intracranial calcifications. High calcium phosphorus product and severe secondary hyperparathyroidism were present in both patients. Furthermore, they both received inappropriately high doses of active vitamin D, even though they failed to respond to this therapy. We suggest to monitor closely the calcium, phosphorus and parathyroid hormone levels during calcitriol therapy and to perform parathyroidectomy, without delay, in patients who were resistant to calcitriol.
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