Primary hyperparathyroidism in Austria: results of an 8-year prospective study.

Serum calcium determinations in 45,217 hospitalized patients during an 8 year period revealed sustained hypercalcemia in 124 (0.3%) patients. Further clinical and biochemical investigations established primary hyperparathyroidism (PHP) in at least 40 (32%) patients, an incidence of PHP of 89.6 +/- 41.5 per 100,000 patients per year. The incidence of PHP in males and females was 31.5 and 124.2 per 100,000, respectively. The highest incidence was found in females greater than 66 years of age (268.8 per 100,000). Nineteen (48%) patients showed classical symptoms of PHP, 14 (35%) patients were minimally symptomatic, and 7 (17%) patients were asymptomatic. The incidence and symptomatology of PHP in Austria is nearly the same as in other countries. Because of the multiple actions of parathyroid hormone in the body, PHP can cause debilitating symptoms but too often it remains undiagnosed clinically. Routine calcium determinations are very important and PHP must always be considered in the differential diagnosis, especially in minimally symptomatic patients.