200 Section - Calciphylaxis Following Parathyroidectomy: A Novel Case Report

Calciphylaxis is a rare, life-threatening vascular calcification disorder most often associated with hyperparathyroidism and end-stage renal disease (ESRD). Parathyroidectomy is considered a treatment for calciphylaxis; paradoxical development following complete gland removal is exceptionally uncommon.

Case Description:

We describe a 74-year-old woman with chronic kidney disease (CKD) stage 4 by cystatin C–based estimated glomerular filtration rate (eGFR) who developed painful necrotic thigh lesions three months after a complete parathyroidectomy. Prior to surgery, she presented with life-threatening hypercalcemia, markedly elevated parathyroid hormone, phosphorus, and creatinine. She required three sessions of temporary dialysis for stabilization. Her acute kidney injury resolved after calcium control, with renal function returning to baseline CKD stage 4. Surgical pathology revealed an atypical parathyroid tumor. Despite successful tumor removal and aggressive postoperative management, she developed calciphylaxis. She underwent multiple incision and drainage (I&D) procedures and received intravenous sodium thiosulfate without improvement.

Discussions:

Initially, there was some trouble with the identification of the medical condition.Upon further conversation, it was evident that the wounds predated the immobility and wheelchair usage. Additionally, phosphorus and parathyroid hormone (PTH) levels were low, which are typically elevated in patients with calciphylaxis. Paradoxically, in these cases there is not a parathyroid hormone driving the hypercalcemia. However, this patient was on the border of chronic kidney disease stage 4 and ESRD. Treatment modality was similar in all four cases as well. IV sodium thiosulfate and wound debridement were utilized.   

 

Conclusions:

Calciphylaxis should be considered in patients presenting with necrotic skin lesions, even in the absence of elevated PTH or in the post-parathyroidectomy setting. This case highlights the importance of avoiding premature dismissal of patient concerns and maintaining a broad differential diagnosis. Interdisciplinary collaboration between nephrology, vascular surgery, dermatology, and pathology is essential for timely diagnosis and management. Early recognition and consultation can prevent misdiagnosis, reduce complications, and improve outcomes.