Phaeochromocytoma and hypercalcaemia

An example of possible pseudohyperparathyroidism associated with a non-endocrine benign tumour is reported. Some of the pertinent factors contributing to hypercalcaemia under these circumstances are reviewed, with particular reference to ectopic hyperparathyroidism and catecholamine-induced endogenous hyperparathyroidism.     

Bedside assessment of hypercalcaemia

Hypercalcaemia results from either primary hyperparathyroidism (PHPT) or malignancy in approximately 90% of cases. PHPT mostly pursues an indolent course, often with evidence of chronicity such as renal stone disease. Malignancy hypercalcaemia is more often recent and aggressive in onset, with the tumour source obvious. The clinical history, physical examination and routine radiology emerge as useful bedside discriminants, compared with subsequent biochemical and hormonal tests. Careful bedside evaluation can yield diagnostic information which compares well with laboratory tests in sensitivity and specificity.     

Malignant phaeochromocytoma and hypercalcaemia.

We describe a case of hypercalcaemia secondary to recurrent malignant phaeochromocytoma. Parathyroid-related protein (PTHrp 1-86) immunoreactivity was identified in plasma and PTHrp was identified by immunocytochemistry in tumour tissue.     

Danazol-induced hypercalcaemia in alphacalcidol-treated hypoparathyroidism

We report a case of idiopathic hypoparathyroidism, maintained on alphacalcidol who developed hypercalcaemia during treatment with danazol for endometriosis.     

Control of hypercalcaemia in thyrotoxicosis

Two thyrotoxic patients with significant hypercalcaemia are described. The hypercalcaemia failed to suppress with hydrocortisone, propranolol and calcitonin but serum calcium fell rapidly to normal with carbimazole treatment. Both patients were subsequently treated surgically and at operation no evidence of parathyroid disease was found. Thyroid disease must be controlled before co-existing parathyroid disease is diagnosed in hypercalcaemic thyrotoxic patients.     

Paraneoplastic hypercalcaemia in ovarian carcinoma

Five patients were seen in whom a raised serum calcium concentration was associated with ovarian carcinoma (clear cell in two cases, cystadenocarcinoma in three). None showed evidence of metastases in bone. The hypercalcaemia occurred as a paraneoplastic phenomenon, but biochemical studies suggested the production of a parathyroid-hormone-like substance. One patient remained free of symptoms of her hypercalcaemia throughout. Paraneoplastic hypercalcaemia due to ovarian carcinoma may be more common than generally recognised and present as a life threatening condition requiring urgent treatment.     

Drugs for the treatment of hypercalcaemia

Hypercalcaemia is ordinarily treated by treatment of the underlying disorder. In some cases, as in malignant disease, in vitamin D poisoning and after a failed parathyroidectomy, the hypercalcaemia itself needs to be treated. A large number of methods have been advocated for this, but phosphate is the drug of choice in most patients. This paper outlines its use, mode of action and side effects and reviews the other methods proposed for the management of hypercalcaemia.     

Cerebral neoplastic angioendotheleosis complicated by hypercalcaemia

This is a case report of a 67 year old man who presented with a fluctuating level of consciousness and myoclonic jerks caused in part by hypercalcaemia. The diagnosis of cerebral neoplastic angioendotheleosis was only made later on brain biopsy and is the first report of the occurrence of hypercalcaemia in neoplastic angioendotheleosis.     

The incidence and causes of hypercalcaemia

A prospective screen for hypercalcaemia in 58,053 hospital in-patients was conducted over 12 months. The incidence of hypercalcaemia was 0.6%, being transient in 19.2% of patients and sustained in the remainder. The most common causes in the sustained group were malignancy (45%) and primary hyperparathyroidism (16.5%). The incidence of primary hyperparathyroidism was 78/100,000 hospital in-patients, and its discovery was directly attributable to the survey in over half the cases.