Kidney Week

Abstract: FR-PO0958

Asymptomatic Severe Hypocalcemia Secondary to Vitamin D Deficiency in a Pediatric Patient

Session Information

• Pediatric Nephrology: Genetic Diseases, Development, Neonatal Nephrology, Glomerular Diseases, and More
  October 23, 2026 | Location: Exhibit Hall A, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Pediatric Nephrology

• 1800 Pediatric Nephrology

Authors

• Nguyen, Sophia T., ECU Health, Greenville, North Carolina, United States

Sophia T. Nguyen, DO

• Tugman, Matthew James, ECU Health, Greenville, North Carolina, United States

Matthew James Tugman, MD

• Park, William M., ECU Health, Greenville, North Carolina, United States

William M. Park, MD

• Gomez Mendez, Liliana Michelle, East Carolina University Brody School of Medicine, Greenville, North Carolina, United States

Liliana Michelle Gomez Mendez, MD

Introduction

Severe hypocalcemia in children can incite life-threatening neurologic and cardiac events, including seizures, tetany, and arrhythmias, with heightened risk in those with underlying renal dysfunction. While severe hypocalcemia is often symptomatic, asymptomatic severe hypocalcemia has been documented and carries significant risk of complications if it is unrecognized.

Case Description

A 14-year-old male with history of posterior urethral valves complicated by acute kidney injury with early urethral valve ablation presented to nephrology clinic with bilateral lower extremity edema. The patient was previously diagnosed with chronic kidney disease stage 2 but was lost to follow-up due to social barriers. Workup for his edema showed nephrotic-range proteinuria, hypoalbuminemia, and severe hypocalcemia (5.3 mg/dL, corrected 6.9 mg/dL). He was notably asymptomatic, and initiated on prednisone, both active and inactive forms of vitamin D, and calcium supplementation. At his return visit, due to insurance barriers, he was unable to receive his prescription medications, and he was on the incorrect vitamin D dose. Genetic testing revealed two mutations in the APOL1 gene consistent with nephrotic syndrome. Repeat labs redemonstrated hypocalcemia and undetectable vitamin D levels. Due to the severity of his hypocalcemia, despite remaining asymptomatic, the patient was referred to the emergency department where workup revealed low serum calcium (5.5 mg/dL, corrected 7.2 mg/dL), low ionized calcium (2.9 mg/dL), and a normal electrocardiogram (EKG). He was treated with intravenous calcium, vitamin D replacement, and steroids. His ionized calcium improved, and he was discharged home. At his follow-up appointment, swelling and proteinuria improved but intact parathyroid hormone was significantly elevated (1096 pg/mL) without much change in his calcium and vitamin D levels.

Discussion

Patients with untreated nephrotic syndrome can present with mild to moderate hypocalcemia and low vitamin D serum levels due to urinary losses. However, most cases with such severe hypocalcemia are rarely asymptomatic. The patient’s asymptomatic presentation and normal EKG suggest chronic hypocalcemia likely due to his undiagnosed and untreated nephrotic syndrome. This case therefore highlights the importance of screening for vitamin D deficiency in pediatric patients with renal dysfunction even in the absence of symptoms.