Pseudo-pseudohypercalcaemia, apparent primary hyperparathyroidism and Waldenström's macroglobulinaemia.

An apparent primary hyperparathyroidism was reported due to pseudo‐pseudohypercalcaemia in a 74–year‐old man with Waldenstrom's macroglobulinaemia. It is important to recognise artificially elevated serum calcium levels so as to avoid erroneous diagnosis, unnecessary investigations and potentially inappropriate treatment.