Rare cause of persistent hypocalcaemia in infancy due to PTH gene mutation

Area of Science:

• Pediatric Endocrinology
• Genetics
• Neonatal Medicine

Background:

• Hypocalcaemia is common in neonates, often transient.
• Persistent hypocalcaemia may suggest endocrine disorders, including hypoparathyroidism.
• Genetic factors, such as DiGeorge syndrome or specific gene mutations (GCM2, CaSR, PTH), are known causes.

Observation:

• A female infant presented with hypocalcaemic convulsions neonatally.
• Laboratory results showed high serum phosphate and low parathyroid hormone (PTH) levels.
• Initial treatment with calcium and vitamin D analogs was effective.

Findings:

• The patient experienced recurrent hypocalcaemic convulsions in infancy after loss to follow-up.
• Clinical exome analysis identified a homozygous mutation in the PTH gene.
• This confirmed a diagnosis of congenital isolated hypoparathyroidism.

Implications:

• This case illustrates a rare genetic cause of isolated hypoparathyroidism.
• It underscores the importance of genetic analysis in persistent neonatal hypocalcaemia.
• Understanding these mutations is crucial for diagnosing and managing rare endocrine disorders.