Neobook — clinical reference

ICD-10 Code: E83.5 + (E21.0/D71)

When serum calcium (corrected for albumin) concentrations exceed the upper limit of normal.

Aetiology

Ambulatory patients: most common cause is hyperparathyroidism (>90% of cases).
Hospitalised patients: malignancies are the most common cause (65% of cases). Hyperparathyroidism accounts for another 25%.
Granulomatous disease (e.g. sarcoid).
Immobilisation in those with high bone turnover.

Investigations

Draw blood for parathyroid hormone (PTH) and simultaneous calcium, phosphate, magnesium, albumin, creatinine and sodium and potassium and 25 hydroxy-vitamin D concentrations.
A detectable PTH in the presence of hypercalcaemia indicates PTH-dependent hyperparathyroidism.

Hypercalcaemia

Patients with moderate/severe hypercalcaemia should be kept well hydrated and may need several litres of fluid.
Avoid thiazide diuretics in the acute setting as they increase serum calcium concentration.
The addition of furosemide has not been shown to be of benefit.

For symptomatic hypercalcaemia:

Sodium chloride solution 0.9%, IV infusion, 4–6 L in 24 hours.
- Monitor urine output.

If still symptomatic after 24 hours and adequate hydration, or if initial serum calcium is > 3 mmol/L:

ADD

Bisphosphonates, e.g.:
- Zoledronic acid, IV infusion, 4 mg over 15 minutes (specialist initiated).
  - eGFR 35 to 60 mL/minute, adjust dose in consultation with specialist

Note
Do not use if eGFR <35 mL/minute

In patients with granulomatous disease and haematological malignancies:

Corticosteroids (intermediate-acting) e.g.:
- Prednisone, oral, 40 mg depending on response, daily.

When a diagnosis of hyperparathyroidism is confirmed or other cause is not obvious.

Standard Treatment Guidelines and Essential Medicines List for South Africa, Hospital Level, Adults 2024 Edition

Hypercalcaemia, including Primary Hyperparathyroidism