Private raised calcium clinic in London, same-day endocrinology.

Symptoms, if any

Mildly raised calcium often causes nothing at all. When it does, the symptoms are famously vague and are routinely attributed to age, stress or the menopause. The old mnemonic is bones, stones, abdominal groans and psychic moans:

• Bones — aches, osteoporosis, fractures
• Stones — kidney stones, and passing large volumes of urine
• Abdominal groans — constipation, nausea, indigestion, occasionally pancreatitis
• Psychic moans — fatigue, low mood, poor concentration, irritability, brain fog
• excessive thirst, muscle weakness, and joint pain

What causes it

• Primary hyperparathyroidism — usually a single benign adenoma on one of the four parathyroid glands. By far the commonest cause in people who are otherwise well.
• Cancer — the commonest cause in people who are unwell, particularly with breast, lung, myeloma or kidney cancer.
• Medicines — thiazide diuretics, lithium, and excessive vitamin D or calcium supplements.
• Sarcoidosis and tuberculosis, and prolonged immobility.
• Familial hypocalciuric hypercalcaemia — a harmless inherited condition that mimics hyperparathyroidism and must be distinguished from it, because surgery does not help and is not indicated.

Assessment

• Repeat calcium with albumin, PTH, vitamin D, kidney function, phosphate and magnesium
• A 24-hour urine calcium, which helps distinguish hyperparathyroidism from the familial condition
• DEXA bone density scan, since bone loss influences whether surgery is recommended
• Kidney ultrasound to look for stones
• Imaging of the parathyroid glands only once the diagnosis is biochemically established, to guide surgery

Treatment

• Parathyroidectomy — removing the overactive gland — cures the condition. It is recommended for symptoms, calcium above a threshold, kidney stones, reduced kidney function, osteoporosis, or age under 50.
• Monitoring is reasonable for mild disease without symptoms or complications: calcium and kidney function annually, bone density every one to two years.
• Keep drinking normally — do not restrict fluids — and stay active.
• Do not stop dietary calcium. Restricting it can worsen the condition by driving PTH higher. Vitamin D deficiency should be corrected, carefully and under supervision.
• Review any thiazide diuretic or lithium.