Endocrine Abstracts

Introduction: Primary hyperparathyroidism (PHP) results from an excessive secretion of parathyroid hormone (PTH), typically leading to hypercalcaemia. This disorder is more common than previously expected, since it is frequently diagnosed in asymptomatic patients.

Objectives: To characterize a group of patients with PHP, in what concerns to: age, clinical presentation, biochemical and imaging evaluation, treatment and evolution.

Patients and methods: Retrospective analysis of the clinical files of patients with PHP followed in our Department.

Results: We studied forty-two patients (21.4% male, 78.6% female), mean age 52.4±17.3 years (21–80). Hypercalcemia was incidentally diagnosed during routine analysis (54.8%), thyroid evaluation (16.7%), investigation of asthenia (9.5%), multiple endocrine neoplasia (7.1%), bone tumours (7.1%) and renal colic (4.8%). In what concerns to clinical presentation, 61.9% were asymptomatic. The symptomatic patients referred mostly asthenia, bone and joint pain. At the diagnosis, biochemical evaluation: total calcium 11.7±1.6 mg/dl (N: 8.8-10.6), ionized calcium 1.5±0.2 mmol/l (0.9–1.1), PTH 310.3±355.4 pg/ml (9–72), phosphorus 2.5±0.9 mg/dl (2.5–4.5) and 24 h-urinary calcium excretion 294.2±152.8 mg (100–300). Ultrasound localized the enlarged parathyroid gland in 90.5% of the patients, (sensitivity 92.8%; mean size 1.7±0.8 cm). Imaging with technetium-99m sestamibi presented fixation in 76.4% (sensitivity 76.2%). Reduced bone mineral density was already present in 78.5% and renal lithiasis in 45.2%. In what concerns to the treatment, 90.5% were submitted to parathyroidectomy (7.9% maintained PHP and 7.9% relapsed). There were some surgical complications: transitory (2.4%) or definitive hypocalcaemia (9.5%) and dysphonia (7.1%). Histology: adenoma (69.2%) or hyperplasia (25.6%). In the first endocrine evaluation after surgery: PTH 63.9±35.8 pg/ml and total calcium 8.9±0.9 mg/dl. At the present moment, 84.2% are cured (PTH 46.25±18.3 pg/ml).

Conclusions: The authors emphasize that 88% of the cases were sporadic and 12% included in a familiar syndrome. Although patients were mostly asymptomatic, there were important bone and kidney consequences. Ultrasound was more sensitive than cintigraphy in the localization of the hyperfunctioning parathyroid gland.