Abstract

Objective: Familial hypomagnesemia with hypercalciuria and nephrocalcinosis (FHHNC) is a rare autosomal-recessive renal tubular disorder. It is characterized by renal wasting of magnesium and calcium, which subsequently leads to bilateral nephrocalcinosis, renal stones, and kidney failure. Early diagnosis of FHHNC is important to prevent morbidity and mortality but due to non-specific symptoms it is difficult to diagnose. In this report, pediatric FHHNC patients are presented to raise awareness about the disease.

Material and Methods: We retrospectively analyzed pediatric FHHNC patients in our hospital between 2010 and 2020.

Results: A total of seven patients, five girls (71.4 %) and two boys (28.5 %) with a median age of four years (min: four months, max:13 years) and a mean follow-up time of 4.4±3.5 years were included. Three patients had been diagnosed incidentally. All patients had nephrocalcinosis, hypercalciuria and high parathormone (PTH) level. One patient had normal serum magnesium level. All patients had high urine fractional excretion of magnesium (FEMg). Five patients had CLDN 16 mutation, and two patients had CLDN19 mutation. None of them had ocular findings. Three patients had kidney failure at the end of the follow-up.

Conclusion: Normal serum magnesium levels do not rule out FHHNC. FEMg value is much more significant in patients with FHHNC. FEMg is recommended in all pediatric patients with nephrocalcinosis even if serum magnesium levels are normal.

Keywords: CLDN16, CLDN19, Hypomagnesemia, Hypercalciuria, Nephrocalcinosis

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Copyright © 2025 The Author(s). This is an open access article distributed under the Creative Commons Attribution License (CC BY), which permits unrestricted use, distribution, and reproduction in any medium or format, provided the original work is properly cited.

How to cite

1.
Aydın Z, Çaycı FŞ, İnözü M, Şahin İ, Kondrad M, Bayrakçı US. Evaluation of children with familial hypomagnesemia with hypercalciuria and nephrocalcinosis. Turk J Pediatr Dis [Internet]. 2025 Jul. 28 [cited 2025 Aug. 23];19(4):149-53. Available from: https://turkjpediatrdis.org/article/view/1103