[Primary hyperparathyroidism: current role of bone densitometry].

Objective: To describe the usefulness of bone densitometry in the diagnosis and follow-up of patients with primary hyperthyroidism (PHPT).
Material and Methods: 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.
Results: 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.
Conclusions: 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.