Definition: Serum Calcium (Ca) ≥ 10.5 mg/dL

Causes

• Most Common Causes (90%):
  • Hyperparathyroidism – Most Common Benign/Outpatient Cause
  • Malignancy
    • Breast Cancer – Most Common Malignant Cause
    • Squamous Cell Carcinoma of the Lung
    • Lytic Bone Lesions
• Less Common Causes:
  • Vitamin D Intoxication
  • Thiazide Diuretics
  • Lithium
  • Familial Hypercalcemic Hypocalciuria (FHH) – CaSR (Calcium-Sensing Receptor) Inactivating Mutations Causing Parathyroid Gland to be Less Sensitive to Calcium
  • Milk-Alkali Syndrome – Excessive Ingestion of Calcium with Absorbable Alkali (Vitamins/Milk)

Severity

• Mild: ≥ 10.5 mg/dL
• Moderate: ≥ 12.0 mg/dL
• Severe/Crisis: ≥ 14.0 mg/dL

Presentation

• “Stones, Bones, Groans, Thrones, and Psychiatric Overtones”
• Stones:
  • Kidney Stones
  • Gallstones
• Bones:
  • Osteoporosis
  • Bone Pain
• Groans:
  • Abdominal Pain
  • Peptic Ulcer Disease (PUD)
  • Pancreatitis
  • Constipation
  • Anorexia
  • Nausea and Vomiting
• Thrones:
  • Polyuria (Urinary Frequency)
  • Polydipsia
• Psychiatric Overtones:
  • Fatigue
  • Delirium
  • Coma

EKG Changes

• Shortened QT Interval
• Bradycardia

Treatment

• Mild: Nothing
• Moderate-Severe: IV Normal Saline (NS) and Furosemide (Lasix)
  • Also Consider:
    • Bisphosphonates (Zoledronic Acid)
    • Calcitonin
    • Dialysis