EC Paediatrics

DiGeorge syndrome, also known as 22q11.2 deletion syndrome, is a genetic disorder caused by a microdeletion on chromosome 22. This condition is associated with various developmental anomalies, including thymic hypoplasia, parathyroid gland dysfunction, and congenital heart defects. A notable and significant aspect of DiGeorge syndrome is hypocalcaemia, or low blood calcium levels, which primarily results from parathyroid hypoplasia or dysfunction. Inadequate secretion of parathyroid hormone (PTH) disrupts calcium homeostasis and may lead to symptoms such as tetany and seizures, along with more severe complications if not addressed timely. Early recognition and prompt management of hypocalcaemia are crucial to preventing life-threatening outcomes. Diagnosis is typically confirmed through genetic testing for the 22q11.2 deletion, while treatment often includes calcium and vitamin D supplementation to restore normal calcium levels. The severity and progression of this disorder can vary widely; some individuals may experience only mild hypocalcaemia, whereas others may encounter more significant medical challenges. A multidisciplinary approach, involving endocrinologists, cardiologists, immunologists, and genetic counsellors, is essential for optimizing long-term health outcomes for individuals with DiGeorge syndrome. In our case, we observed an unusual presentation characterized by normal total calcium levels and elevated corrected calcium levels.

 Keywords: DiGeorge Syndrome; DGS; Hypercalcemia; Hypocalcaemia

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