Hypervitaminosis D-Induced Hypercalcemia and Nephrocalcinosis: Strategies for Prompt Resolution

Dr Jahnavi M*, Dr Shruti Sastry*, Dr Kavitha N Bhat*.

1. Senior Specialist, Pediatric Endocrinology, Aster Whitefield.

2. Consultant, Pediatric Endocrinology, Aster CMI Hospital and Aster RV Hospital.

3. Lead Consultant, Pediatric Endocrinology, Aster Hospitals, Bengaluru Cluster.

*Correspondence to: Dr Jahnavi M, Dr Shruti Sastry & Dr Kavitha N Bhat.

Copyright

© 2025: Dr Jahnavi M. et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Received: 23 Aug 2025

Published: 01 Sep 2025

Introduction

Hypercalcemia secondary to vitamin D intoxication has been rising with the availability of several formulations over the counter. We report on the management of one such case.

Case Details

A 6-month-old baby presented with failure to thrive. Initial lab investigations revealed hypercalcemia (serum calcium: 18.2 mg/dL), low intact parathyroid hormone (6.2 pg/mL), and elevated 25(OH) vitamin D levels (>100 ng/mL). Additional labs showed normal levels of phosphorus (6.5 mg/dL), alkaline phosphatase (146.5 U/L), blood urea nitrogen (16.2 mg/dL) and creatinine (0.3 mg/dL). The urine calcium/creatinine ratio was elevated to 1.89 (>0.4). Ultrasonography showed bilateral echogenic renal pyramids suggestive of nephrocalcinosis. On further questioning, the mother reported giving regular vitamin D supplementation obtained through an online store (Arachitol Nano 60,000 IU/5 mL) since birth—administering half a dropper (approximately 0.5 mL) daily for at least 3 months and on and off over the next 3 months. This resulted in a daily intake of at least 6,000 IU of vitamin D for around 3- 6 months. Child was treated with hyperhydration, IV pamidronate, calcitonin, and a single dose of furosemide. Calcium levels normalized over the next 3 days.

Discussion

Vitamin D toxicity has been well reported in literature. The management of hypercalcemia includes intravenous hydration, loop diuretics, calcitonin, and intravenous bisphosphonates. IV bisphosphonates cause prompt normalization of serum calcium levels. Adverse effects of bisphosphonates include allergic reactions, fever, hypocalcemia, or hypophosphatemia. Our child developed hypophosphatemia requiring phosphorus supplementation. While we preferred pamidronate over zoledronic acid due to prior experience, literature suggests zoledronic acid may be easier to administer with lesser side effects.

Conclusion

This report highlights:

1. The need for public and professional awareness regarding the risks of unsupervised vitamin D supplementation.

2. Combined use of calcitonin and bisphosphonates is effective for prompt reduction in calcium levels.

References

1.Gupta P, Dabas A, Seth A, Bhatia VL, Khadgawat R, Kumar P, Balasubramanian S, Khadilkar V, Mallikarjuna HB, Godbole T, Krishnamurthy S, Goyal JP, Bhakhri BK, Ahmad A, Angadi K, Basavaraj GV, Parekh BJ, Kurpad A, Marwaha RK, Shah D, Munns C, Sachdev HPS. Indian Academy of Pediatrics Revised (2021) Guidelines on Prevention and Treatment of Vitamin D Deficiency and Rickets. Indian Pediatr. 2022 Feb 15;59(2):142-158.

2. Vogiatzi MG, Jacobson-Dickman E, DeBoer MD; Drugs, and Therapeutics Committee of The Pediatric Endocrine Society. Vitamin D supplementation and risk of toxicity in pediatrics: a review of current literature. J Clin Endocrinol Metab. 2014 Apr;99(4):1132-41.

3.   Virú-Loza MA, Alvarado-Gamarra G, Zapata-Sequeiros RI, Flores-Nakandakare HF. Life-threatening hypercalcemia in a child with vitamin D intoxication due to parental self-medication: A case report. SAGE Open Medical Case Reports. 2024;12.

4. Diaz A, Velasquez S. SAT-510 Hypercalcemia Secondary to Vitamin D Intoxication and Nephrocalcinosis in 2 Children. J Endocr Soc. 2019 Apr 30;3(Suppl 1): SAT-510.