Unsuspected hypercalcemia among adults in hospital.

Physicians usually fail to recognize an abnormal serum calcium level and often do not arrive at a definite conclusion about its cause. Yet hypercalcemia, even when minimal, indicates potentially serious underlying disease. This review of the records of about 12 000 adults in hospital showed a prevalence of unsuspected hypercalcemia of 1.4%, a 24% rate of recognition of the abnormal serum level and a 71% rate of correct diagnosis (though often presumptive) of the underlying cause by the attending physician, and a possible prevalence of unsuspected hyperparathyroidism of 0.3%. Because of other considerations, however, the prevalence estimates are probably for too low.