Primary hyperparathyroidism is a common disorder of mineral metabolism characterized by incompletely regulated, excessive secretion of parathyroid hormone from one or more of the parathyroid glands. In adults with the disease, a single, benign adenoma is seen approximately 80 percent of the time, with multiple gland involvement comprising most of the remaining patients. Very rarely, a parathyroid cancer is responsible but it is seen in less than 0.5 percent of patients with primary hyperparathyroidism. In this article, we will review important clinical and diagnostic features of asymptomatic primary hyperparathyroidism as well as considerations for surgical or medical management of the disease. O hiperparatiroidismo primário é uma distúrbio comum do metabolismo mineral, caracterizado por um excesso de secreção do hormônio das paratiróides, de uma ou mais glândulas paratiroidianas. Nos pacientes adultos portadores da doença, um adenoma único é responsável por aproximadamente 80% dos casos, e o envolvimento de múltiplas glân-dulas pelo restante dos casos. Muito raramente um câncer de paratiróide é a causa, sendo visto em menos de 0,5% dos pacientes com hiperparatiroidismo. Neste artigo, revisaremos as características clínicas e diagnósticas do hiperparatiroidismo primário assintomático, bem como o tratamento clínico e cirúrgico.
DIAGNOSIS
SINCE IN PRIMARY HYPERPARATHYROIDISM, parathyroid hormone (PTH) is oversecreted, a reliable immunoassay for PTH is essential. The currently available immunoradiometric assay (IRMA) has the requisite sensitivity and specificity, revealing PTH levels that are either frankly elevated or in the upper range of normal. Even though the PTH is sometimes technically in the upper normal range, it is abnormal considering the presence of hypercalcemia. Moreover, in malignancy, the other most common cause of hypercalcemia, the PTH level is classically suppressed even when the cause of the malignancy-related hypercalcemia is parathyroid hormone related protein (PTHrP). Despite the reliability of the IRMA for PTH in general