Kidney Week

Abstract: TH-PO176

Unexpected Early Hypercalcemia after Parathyroidectomy in a Patient with Tumoral Calcinosis and Severe Calciphylaxis

Session Information

• CKD-MBD: Clinical
  October 24, 2024 | Location: Exhibit Hall, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Bone and Mineral Metabolism

• 502 Bone and Mineral Metabolism: Clinical

Authors

• Gonzalez Medina, Ana Cristina, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Ciudad de Mexico, Ciudad de México, Mexico

Ana Cristina Gonzalez Medina, MD

• Canaviri, Vianca Anabel, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Ciudad de Mexico, Ciudad de México, Mexico

Vianca Anabel Canaviri, APN

• Ruelas Villavicencio, Ana Lilia, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Ciudad de Mexico, Ciudad de México, Mexico

Ana Lilia Ruelas Villavicencio, MD

• Parra, Paul Armando, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Ciudad de Mexico, Ciudad de México, Mexico

Paul Armando Parra

• Perez Diaz, Ivan, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Ciudad de Mexico, Ciudad de México, Mexico

Ivan Perez Diaz, MD, PhD

• Paz Cortes, Jose Armando, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Ciudad de Mexico, Ciudad de México, Mexico

Jose Armando Paz Cortes, MBBS

• Ramirez-Sandoval, Juan Carlos, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Ciudad de Mexico, Ciudad de México, Mexico

Juan Carlos Ramirez-Sandoval, MD, PhD

Introduction

Hypocalcemia due to hungry bone syndrome commonly occurs after total parathyroidectomy (tPTX) in kidney failure patients. This is a paradoxical hypercalcemia case after tPTX in a patient with severe calcific uremic arteriolopathy (CUA) and extensive extraosseous calcium deposits (tumoral calcinosis, TC).

Case Description

A 54-year-old woman with kidney failure on hemodialysis for 4 years (2X/week), admitted to the emergency room with fever and severe neuropathic pain in extremities. Physical examination showed huge ischemic ulcers on lower limbs (see figure). Additionally, asymptomatic palpable masses were found in her shoulders, knees and hips. A skin biopsy confirmed the diagnosis of CUA, while a PET-CT scan revealed extensive vascular calcifications and calcium phosphate deposits (CPD) in soft tissues and periarticular areas (TC). Lab tests revealed severe hyperparathyroidism (HPT) with iPTH 2049pg/mL, alkaline phosphatase (ALP) 245U/L, normocalcemia (free calcium 4.5 mg/dL), hyperphosphatemia (6.5 mg/dL) and low vitamin D.
She received IV antibiotics, surgical debridement, hemodialysis (HD), calcimimetics and opioids. A tPTX was performed (post-surgery iPTH <50pg/mL). However, she experienced sustained elevations in calcium levels (free calcium >7mg/dL), which required frequent HD for lowering. After tPTX, pain intensity decreased as did ALP, iPTH remained low and ALP levels, yet hypercalcemia persisted. Other causes of hypercalcemia were discarded.

Discussion

We present a novel case of early hypercalcemia development post-tPTX in a patient with CUA and extensive CPD. Mobilization of calcium from extraosseus stores and a poor bone resorption (early adynamic bone disease) seem the main cause of early hypercalcemia in this case. While tPTX has proven effective in managing TC and CUA associated with severe HPT, paradoxical hypercalcemia after tPTX may occur early in cases with extensive extraosseouss CPD.

Clinical presentation and evolution