[Primary hyperparathyroidism: current role of bone densitometry]

To describe the usefulness of bone densitometry in the diagnosis and follow-up of patients with primary hyperthyroidism (PHPT).

Retrospective review of 48 patients with PHPT; 27 received surgical treatment and 21 medical treatment. Radiologic and biochemical findings and bone mass were evaluated at the start of the study and after one and two years.

All patients had elevated PTH levels and 87% had normal or moderately increased calcemia. The most common clinical presentations were renal colic (34%) and the absence of symptoms (22.8%). The sensitivity of scintigraphy was 75% and the sensitivity of ultrasonography was 12%. We found osteopenia in 70.3% of patients and osteoporosis in 81.3%, fundamentally in the radius and spine. Bone mass at one year and at two years remained similar in the femur (73.8%) and spine (81.8%) in 58% and 50% of the patients, respectively. Increased bone mass was seen in the femur (30.4%) in 13.6% of the patients and in the spine (33.3%) in 50% of the patients. This increase was greater in the group that received surgical treatment. Calcemia and PTH were decreased by 69.2% and 76.9 %, respectively, in the patients that underwent surgery. In the group that received medical treatment, calcemia remained similar and PTH was decreased by 50%. Fractures developed in 21.8% of the patients.

Densitometry assesses the repercussions of the disease on bone mass at the start of treatment and after treatment. Osteoporosis is a common finding. Gains in bone mass occurred fundamentally in patients that had undergone surgery. Bone mass remained similar in a high percentage of patients in both groups.