Calcium and bone

Who to refer: 

Patients with biochemical abnormalities of calcium, PTH and vitamin D

Hypercalcaemic Conditions

• Patients with suspected primary hyperparathyroidism-raised or inappropriately normal PTH in the context of hypercalcaemia
  • The endocrine team may organise pre-clinic investigations – please indicate if the patient is not mobile enough to undertake a DEXA scan
  • Do not arrange parathyroid imaging – this will be organised by the endocrine team if necessary
  • If patient is frail/elderly and unlikely to be suitable for parathyroidectomy, particularly if modest hypercalcaemia <2.9 mmol/l can be referred via the Diabetes & Endocrine inbox for email advice only. Where appropriate we can provide advice without bringing the patient to clinic.
• Patients with osteoporosis, renal stones or other suspicion of primary hyperparathyroidism with high normal calcium (e.g. >2.5) on two occasions and high PTH may have normocalcaemic hyperparathyroidism and can be referred.
• Hypercalcaemia provided the cause is not obviously malignant, myeloma, sarcoidosis or renal.  A suppressed PTH would suggest a non-endocrine cause of hypercalcaemia and obvious malignancy or myeloma should be excluded prior to referral to the endocrine clinic.
• Refer urgently to endocrinology as outpatient if calcium > 2.9 mmol/l in the context of primary hyperparathyroidism. Consider inpatient referral via the medical admissions bleep for calcium > 3.1 mmol/l.

Hypocalcaemic/Vitamin D Deficient Conditions

• Patients with primary hypoparathyroidism should be referred to endocrinology (Low PTH, low Ca) – particularly in patients with history of neck surgery).
• Persistent hypocalcaemia with high PTH, normal vitamin D and normal magnesium. This pattern in rare cases can be in keeping with pseudohypoparathyroidism.
• Most patients with vitamin D deficiency can be managed in the community (see ‘Who not to refer’ below).    Patients with low vitamin D, raised PTH and RAISED calcium should be referred as they may have concomitant primary hyperparathyroidism, in which case vitamin D treatment will probably cause Ca2+ levels to rise further.
• Patients with calcium < 1.9 mmol/l, or acute symptomatic hypocalcaemia of any level, should be referred via the medical admissions bleep for inpatient investigation and management

 Osteoporosis secondary to endocrine disease e.g.

• Hypogonadism
• Hyperparathyroidism
• Cushing’s syndrome
• Uncontrolled thyrotoxicosis

Who not to refer:

Uncomplicated Vitamin D deficiency without other biochemical abnormalities.

25(OH) vitamin D level <25 nmol/l, which is indicative of Vitamin D deficiency. If vitamin D deficiency is uncomplicated (eg no other associated biochemical abnormalities or only modest elevations of ALP and PTH), it is usually appropriate to manage the patient in primary care. Please see advice on Vitamin D in adults (see resources below).

Vitamin D in Renal and GI Disease

Patients with renal failure who may need ‘activated’ vitamin D, or lower doses of vitamin D, should be discussed with the renal team. Patients with GI disorders who may require high doses or parenteral administration of vitamin D should be discussed with GI.  In general, if you are unsure whether patients meet referral criteria, please email the Diabetes & Endocrine inbox: diabetes.endocrinology@borders.scot.nhs.uk    

Hypercalcaemia with suppressed PTH secondary to known/suspected malignancy

Refer to oncology

Hypercalcaemia with suppressed PTH secondary to known sarcoidosis

Refer to respiratory

Low/normal (e.g. calcium >1.9) hypocalcaemia which is asymptomatic with elevated PTH and low vitamin D

This is suggestive of secondary hyperparathyroidism in response to low calcium and vitamin D deficiency which should be corrected.

Severe/Symptomatic Hypocalcaemia

Those with severe hypocalcaemia (Ca2+ <1.9mmol/l - sometimes associated with muscle twitches, convulsions, Chvostek’s sign, Trousseau’s sign, carpal spasm, papilloedema, prolonged QT interval on ECG) or hypomagnesaemia, who may need iv replacement should be directly referred same day to medical registrar on call

Osteoporosis with no known underlying endocrine condition

Refer to rheumatology

How to refer

Please send referrals to Endocrinology through SciGateway:

Borders General Hospital -> Endocrinology & Diabetes -> Borders General Referral

If any queries please contact the endocrinology email advice on: diabetes.endocrinology@borders.scot.nhs.uk

For investigation of hypercalcaemia, NICE guidance is to measure PTH after 2 calcium readings above normal, or two readings >2.5 with clinical suspicion of primary hyperparathyroidism (e.g. osteoporosis/renal calculi). For patients with particularly severe hypercalcaemia an earlier PTH may be appropriate.

It is usually appropriate to manage uncomplicated vitamin D deficiency in adults in primary care.  Please see advice on Vitamin D in adults (see reousources below). 

Vitamin D Deficiency Guideline | Right Decisions

diabetes.endocrinology@borders.scot.nhs.uk