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Hypocalcaemia mimicking long QT syndrome: case report
Jasveer S Mangat1, Jan Till, Nicola Bridges
1Guys and St Thomas NHS Trust, London, UK. jasveer_mangat@yahoo.com
European Journal of Pediatrics
|May 9, 2007
Summary
A teenage girl experienced fainting spells due to low calcium levels caused by hypoparathyroidism. Supplementation resolved her symptoms and corrected her prolonged QT interval, emphasizing the need for comprehensive diagnosis.
Area of Science:
- Cardiology
- Endocrinology
- Genetics
Background:
- Prolonged QT interval on electrocardiogram (ECG) can be associated with serious cardiac events.
- Hypoparathyroidism is a rare endocrine disorder characterized by insufficient parathyroid hormone production, leading to hypocalcemia.
Observation:
- A teenage female presented with exertional syncope and a significantly prolonged QT segment on her ECG.
- Laboratory investigations revealed severe hypocalcemia, subsequently diagnosed as hypoparathyroidism.
Findings:
- Treatment with oral calcium and vitamin D supplementation led to the resolution of hypocalcemia.
- The patient's syncope episodes ceased, and the QT segment on ECG normalized after treatment.
Implications:
- This case underscores the importance of considering endocrine disorders, specifically hypoparathyroidism, in the differential diagnosis of prolonged QT intervals and syncope.
- Early diagnosis and management of hypocalcemia can prevent potentially life-threatening cardiac arrhythmias and neurological complications.
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