Can hypocalcemia (low calcium levels) cause extrapyramidal symptoms (EPS)?

Hypocalcemia Can Cause Extrapyramidal Symptoms (EPS)

Yes, hypocalcemia can cause extrapyramidal symptoms (EPS) and various other movement disorders. 1, 2

Neurological Manifestations of Hypocalcemia

• Hypocalcemia can induce or worsen movement disorders, including abnormal involuntary movements of any sort, which encompasses extrapyramidal symptoms 1
• Neuromuscular irritability is one of the most common manifestations of hypocalcemia, presenting as tetany, muscle cramps, and spasms 2
• Hypocalcemia can present with extrapyramidal symptoms alongside other neurological manifestations such as seizures and altered mental status 3
• Movement disorders associated with hypocalcemia may include:
  • Dystonia 1
  • Myoclonus 1
  • Tremors 1
  • Motor tics 1
  • Parkinsonism-like symptoms 1

Pathophysiology and Clinical Context

• Calcium plays a crucial role in neuromuscular function, and its deficiency leads to increased neuronal excitability 2
• The severity of extrapyramidal symptoms typically correlates with both the absolute level of hypocalcemia and the rapidity of its development 3
• Hypocalcemia affects neurotransmission in the basal ganglia, which can manifest as extrapyramidal symptoms 2
• In patients with chronic hypocalcemia, symptoms may be more subtle compared to acute presentations 4

Risk Factors and Special Populations

• Patients with 22q11.2 deletion syndrome have a particularly high risk of hypocalcemia (80% lifetime prevalence) and associated movement disorders 1
• Hypoparathyroidism (either primary or post-surgical) is a common cause of hypocalcemia that can lead to EPS 4
• Biological stress (surgery, fracture, injury, childbirth, infection) increases the risk of hypocalcemia and potential neurological symptoms 1
• Consumption of alcohol or carbonated beverages, especially colas, may worsen hypocalcemia 1

Diagnosis and Assessment

• Measure pH-corrected ionized calcium levels, which is the most accurate method to diagnose hypocalcemia 2
• Additional important laboratory tests include:
  • Parathyroid hormone (PTH) levels 2
  • Magnesium levels (hypomagnesemia can contribute to hypocalcemia) 2
  • Thyroid function tests 2
  • Renal function parameters 2
• Neurological assessment should evaluate for other manifestations of hypocalcemia beyond EPS, including tetany, seizures, and cognitive changes 2

Management Approach

• Acute symptomatic hypocalcemia with EPS requires immediate intravenous calcium administration, typically calcium gluconate 5, 6
• For chronic hypocalcemia management:
  • Daily calcium and vitamin D supplementation 2
  • Magnesium supplementation if hypomagnesemia is present 2
  • For severe cases, hormonally active vitamin D metabolites (calcitriol) may be needed 2
• Targeted monitoring of calcium concentrations is essential, especially during vulnerable periods 2

Important Clinical Considerations

• Extrapyramidal symptoms due to hypocalcemia are reversible with appropriate calcium correction 7
• Hypocalcemia-induced neuropsychiatric symptoms, including EPS, may be misdiagnosed as primary psychiatric disorders 7
• Overcorrection of calcium can lead to hypercalcemia, renal calculi, and renal failure 2
• Regular monitoring of calcium levels is essential for patients with chronic hypocalcemia, with special attention during periods of increased risk 2