hypocalcemia /hī′pōkalsē″mē·ə/ [Gk, hypo + L, calx, lime; Gk, haima, blood] , a deficiency of calcium in the serum that may be caused by hypoparathyroidism, vitamin D deficiency, kidney failure, acute pancreatitis, or inadequate amounts of plasma magnesium and protein. Normal serum calcium levels range from 8.5 to 10.5 mg/dL. Mild hypocalcemia is asymptomatic. Severe hypocalcemia is characterized by cardiac arrhythmias and tetany with hyperparesthesia of the hands, feet, lips, and tongue. The underlying disorder is diagnosed and treated, and calcium is given by mouth or IV infusion. Hypocalcemia is also seen in dysmature newborns, in infants born of mothers with diabetes, or in normal babies of normal mothers delivered after a long or stressful labor and delivery. The condition is signaled by vomiting, twitching of extremities, poor muscle tone, high-pitched crying, and difficulty in breathing. Also spelled hypocalcaemia. See also Chvostek’s sign, Chvostek-Weiss sign, tetany. −hypocalcemic, adj.
