Endocr Dev 2009 3;16:93-114. Epub 2009 Jun 3.
Department of Child Health, Southampton University Hospital Trust, Tremona Road, Southampton, UK.
Hypercalcaemia is a rarer problem in children than that of hypocalcaemia. However, when it does occur, it is a condition that requires proper diagnosis before correct treatment can be instituted. Problems may arise either because of excess PTH secretion, e.g. because of parathyroid tumour, or because of inactivating mutations of the calcium-sensing receptor or because some other factor, such as vitamin D or PTHrP, causes hypercalcaemia independently of PTH. In the latter instance, PTH secretion is suppressed. It is often useful to get a clue to the aetiology by examining the urine calcium concentration as this may guide one towards the correct diagnosis. Treatment is aimed at either removing the source of the excess PTH or whichever other factor is involved. In some cases treatment is not necessary as the hypercalcaemia remains asymptomatic and does not cause any problems. If the underlying problem cannot be treated directly, measures can often be taken to reduce the plasma calcium by medical means which can sometimes be used as an interim measure before definitive treatment is undertaken.