Phenotype of Idiopathic Infantile Hypercalcemia Associated with the Heterozygous Pathogenic Variant of SLC34A1 and CYP24A1

Teofana Otilia Bizerea-Moga; Flavia Chisavu; Cristina Ilies; Orsolya Olah; Otilia Marginean; Mihai Gafencu; Gabriela Doros; Ramona Stroescu

doi:10.3390/children10101701

Phenotype of Idiopathic Infantile Hypercalcemia Associated with the Heterozygous Pathogenic Variant of SLC34A1 and CYP24A1

Children (Basel). 2023 Oct 17;10(10):1701. doi: 10.3390/children10101701.

Authors

Teofana Otilia Bizerea-Moga^{1

2}, Flavia Chisavu^{3

4}, Cristina Ilies^{2

5}, Orsolya Olah^{2

6}, Otilia Marginean^{1

2}, Mihai Gafencu^{3

7}, Gabriela Doros^{3

7}, Ramona Stroescu^{1

3}

Affiliations

¹ Department XI of Pediatrics-1st Pediatric Discipline, Center for Research on Growth and Developmental Disorders in Children, 'Victor Babeș' University of Medicine and Pharmacy Timișoara, Eftimie Murgu Sq. No. 2, 300041 Timișoara, Romania.
² 1st Pediatric Clinic, 'Louis Țurcanu' Children's Clinical and Emergency Hospital, Iosif Nemoianu 2, 300011 Timișoara, Romania.
³ 4th Pediatric Clinic, 'Louis Țurcanu' Children's Clinical sand Emergency Hospital, Iosif Nemoianu 2, 300011 Timișoara, Romania.
⁴ Centre for Molecular Research in Nephrology and Vascular Disease, Faculty of Medicine 'Victor Babes', 300041 Timișoara, Romania.
⁵ Department III of Functional Sciences-Pathophysiology Discipline, 'Victor Babeș' University of Medicine and Pharmacy Timișoara, Eftimie Murgu Sq. No. 2, 300041 Timișoara, Romania.
⁶ Department VIII of Neuroscience-Psychology Discipline, 'Victor Babeș' University of Medicine and Pharmacy Timișoara, Eftimie Murgu Sq. No. 2, 300041 Timișoara, Romania.
⁷ Department XI of Pediatrics-3rd Pediatric Discipline, 'Victor Babeș' University of Medicine and Pharmacy Timișoara, Eftimie Murgu Sq. No. 2, 300041 Timișoara, Romania.

Abstract

Idiopathic infantile hypercalcemia (IIH) is a rare genetic disease, also called hypersensitivity to vitamin D3. The molecular heterogeneity allows for the differentiation between the two forms; IIH type 1 caused by CYP24A1 genetic variants and IIH type 2 associated with SLC34A1 mutations. The affected individuals express a variety of symptoms: hypercalcemia, hypercalciuria, suppressed intact parathormone levels (PTH), nephrocalcinosis, elevated levels of serum 1,25 (OH)2-vitamin D3 or inappropriately normal levels, and kidney phosphate wasting. The present paper describes three cases of IIH with heterozygous mutations in SLC34A1 and CYP24A1 genes, respectively. The genetic diagnosis is of paramount importance for proper treatment and the prediction of long-term outcomes.

Keywords: CYP24A1; SLC34A1; idiopathic infantile hypercalcemia; nephrocalcinosis.

Publication types

Case Reports

Grants and funding

This research received no external funding.