Magnesium Matters: Clinical and Endocrine Lessons from Paediatric Case Studies

Abstract

Hypomagnesemia in children is an uncommon but potentially life-threatening electrolyte disorder associated with significant neurological and endocrine manifestations. Due to its close physiological relationship with calcium metabolism and parathyroid hormone regulation, magnesium deficiency often presents with refractory hypocalcaemia, leading to delayed diagnosis. We report two children who presented with recurrent drug-resistant seizures and persistent hypocalcaemia despite adequate calcium and vitamin D supplementation. Further biochemical evaluation revealed profound hypomagnesemia, prompting investigation for an underlying genetic cause. Genetic analysis confirmed congenital familial hypomagnesemia due to a pathogenic mutation affecting intestinal magnesium absorption, consistent with a TRPM6-related disorder. Correction of magnesium deficiency resulted in cessation of seizures and normalization of calcium homeostasis, emphasizing the critical role of magnesium in neuromuscular stability. Both children were initiated on lifelong oral magnesium supplementation and showed sustained clinical improvement on follow-up. These cases highlight the importance of considering hypomagnesemia in children presenting with refractory seizures and persistent hypocalcaemia. Early recognition of congenital familial hypomagnesemia is essential to avoid misdiagnosis, prevent unnecessary investigations, and ensure timely initiation of targeted therapy, thereby reducing long-term neurological morbidity.