Parathyroid venous sampling and ultrasonography in primary hyperparathyroidism due to multigland disease

The results of pre-operative venous sampling and ultrasonography in 20 patients with primary hyperparathyroidism, who were shown histologically to have multigland disease, were reviewed. Ultrasonography (15 patients) demonstrated abnormal parathyroid tissue in 46% (seven patients), but correctly predicted only 33% of the involvement or non-involvement of individual glands. The main deficiency was the high number of false negatives. Parathyroid venous sampling (19 patients) showed elevated levels of parathyroid hormone in 18 (94.7%), but overall the sites of normal and abnormal glands were predicted in 56 of 76 sites (73.6%). The investigation was misleading in one patient (5.2%), in that no abnormal glands were predicted. The sampling maps of the above 19 patients were randomly mixed with those of 100 consecutive patients, whose disease was due to a single adenoma. All but one of the multigland disease cases were identified correctly but six of the single adenoma patients were predicted as having two glands involved, and were therefore thought to be multigland. The usefulness of, and difficulties in, diagnosing multigland disease in primary hyperparathyroidism are discussed.