Background. Are double parathyroid adenomas a discrete clinical entity
or are all hyperplastic parathyroid glands of varying size? This inve
stigation was done to determine whether patients with persistent or re
current hyperparathyroidism and double adenomas (DA) differ in clinica
l profile or in response to treatment from patients with hyperplasia.
Methods. From 1982 to 1993, 37 unselected patients with persistent (11
) or recurrent hyperparathyroidism (26) were treated. Twenty-one had D
A and 16 had hyperplasia. DAs were defined as two abnormal and two nor
mal parathyroid glands. Results. Patients with persistent or recurrent
hyperparathyroidism caused by DA were older and had more muscle weakn
ess, neuropsychiatric disorders, constipation and weight loss (p < 0.0
01) than patients with persistent or recurrent hyperparathyroidism cau
sed by hyperplasia. Nephrolithiasis was more common in, patients with
recurrent hyperparathyroidism caused by hyperplasia than in patients w
ith recurrent hyperparathyroidism caused by DA (p < 0.001). Serum Ca2 levels before operation were similar in these groups with variable pa
rathyroid hormone levels. No recurrences occurred in either group (DA
[mean, 6 yr]; hyperplasia [mean, 5 yr]). Postoperative levels of serum
Ca2+ and parathyroid hormone were normal in both groups. Conclusions.
Patients with persistent or recurrent hyperparathyroidism caused by D
A are older, have different clinical manifestations, and are cured by
resection of the second adenoma, These findings support the concept th
at DA and hyperplasia are distinct entities.