Endocrine Abstracts

BACKGROUND: Acromegaly is a chronic debilitating disease, which can also affect calcium metabolism. Hypercalciuria is a common finding but hypercalcaemia is rare and has been reported in 0-10% of cases in various studies involving small number of patients.

AIM: To investigate the prevalence and aetiology of hypercalcaemia among patients with acromegaly.

PATIENTS AND METHODS: The medical records of 145 patients who presented to our Department with acromegaly between 1985-2004 were reviewed. The diagnosis of hypercalcaemia was established using the corrected value of total calcium according to this formula: corrected calcium (mmol/l) = measured calcium + 0.02X(40-albumin [g/L]).

RESULTS: Five patients (3 females) with hypercalcaemia were identified (3.4%). The median age at diagnosis of acromegaly was 53 years (range: 29-64). In 3 patients hypercalcaemia was found during the initial evaluation for acromegaly. In the rest the diagnosis was established during the follow-up period: in one subject 12 months and in the other 32 months after the diagnosis of acromegaly. All patients were hypertensive and those on treatment were receiving medications not interfering with calcium metabolism. The cause of hypercalcaemia was primary hyperparathyroidism (PHPT) in 3 patients, sarcoidosis in one and not clarified in the last one, in whom serum calcium was normalized after achieving biochemical remission of acromegaly. Calcium levels in the patient with sarcoidosis returned to normal range after treatment with steroids. One of the subjects with PHPT underwent genetical screening for MEN-1 but no mutations were found.

CONCLUSIONS: Hypercalcaemia was detected in 3.4% of patients with acromegaly in our series. However, a raised calcium level in these patients needs further investigation to elucidate the aetiology, as it may not always be attributed to MEN-1.