Hypomagnesemia due to two novel TRPM6 mutations

Area of Science:

• Genetics
• Pediatrics
• Biochemistry

Background:

• Transient neonatal hypoparathyroidism is a common cause of hypocalcemia and hypomagnesemia.
• Magnesium channel defects are an underrecognized cause of these electrolyte imbalances in neonates.

Observation:

• A case of an 8-day-old Hispanic male presenting with seizures due to persistent hypomagnesemia and hypocalcemia.
• Initial treatment with calcitriol and calcium carbonate normalized calcium, while oral magnesium sulfate improved magnesium levels.
• Discontinuation of magnesium led to recurrence of hypomagnesemia and seizures, necessitating continuous, high-dose oral magnesium supplementation.

Findings:

• The patient was found to have primary renal magnesium wasting.
• Genetic testing revealed compound heterozygous mutations in the TRPM6 gene, indicating a genetic basis for the magnesium imbalance.

Implications:

• This case highlights two novel TRPM6 mutations in a new ethnic group.
• Recognizing and diagnosing disorders of magnesium imbalance, including genetic causes like TRPM6 mutations, is critical for effective management and preventing severe neurological complications in neonates.