Overview
Hypocalcaemia describes a low serum calcium ion concentration.
Causes
- Destroyed/removed parathyroid glands
- Hypomagnesaemia
- Vitamin D deficiency
- Chronic kidney disease
- Hyperphosphataemia
- Acute pancreatitis
- Acute rhabdomyolysis
- Tumour lysis
Presentation
Symptoms are generally correlated with the severity and speed of the fall in calcium. They are the result of increased neuromuscular excitability. Neuromuscular excitability occurs due to a reduction in the threshold amount of calcium ions needed for depolarisation. This occurs because calcium ions block sodium ion channels and inhibit the depolarisation of muscles.
Features may be:
- Asymptomatic – in mild cases
- Tetany
- Muscle cramps
- QT prolongation
- Seizures
Management
- Management involves using IV calcium gluconate and treating the underlying cause
Complications
- Arrhythmia
- Seizures
- Tetany
