Hypocalcaemia is common immediately after total thyroidectomy, however permanent Hypoparathyroidism only occurs in 1-2% of cases.
Our experience is that Alfacalcidol and calcium supplement therapy is often continued long-term, particularly in patients with a diagnosis of thyroid cancer; this probably relates to attention being paid to other areas of priority after thyroidectomy (radioiodine ablation, challenge scans, interruption and reinstitution of thyroid hormone therapy).
Long-term therapy with Alfacalcidol and calcium supplements are associated with risks of renal impairment and should only be continued if essential and with continuing monitoring.
We studied 42 patients (31 with thyroid cancer, 11 with benign thyroid disease) recruited over a period of 19 months. Twenty patients were receiving both Alfacalcidol and calcium supplements, 3 patients Alfacalcidol alone and 19 patients calcium supplements alone.
At entry mean (SD) values were serum calcium 2.16 (0.13) mmol/l, serum PTH 19.8 (13.7) ng/l (NR10-60), urine calcium/creatinine ratio 0.39 (0.22) (NR 0-0.7).
The dose of Alfacalcidol and calcium supplements was gradually reduced. After a median of 7 months (range 1-15) of follow-up, 12 patients were able to stop Alfacalcidol and calcium supplements while maintaining a normal serum corrected calcium and nine patients had the dose of Alfacalcidol reduced.
The duration of Alfacalcidol and calcium supplements did not correlate with ability to stop treatment (p>0.05).
Most patients, including those who were able to come off Alfacalcidol and calcium supplements, experienced transient hypocalcaemic symptoms following decrements in the dose of supplements.
In conclusion, Alfacalcidol and calcium supplements can be reduced if not stopped while maintaining eucalcaemia, in many patients with post-thyroidectomy hypocalcaemia, though transient symptoms of hypocalcaemia are experienced by most.
Counselling and support in a specialist nurse clinic setting provides useful support and the necessary monitoring required for a successful outcome.