Hypocalcaemic Tetany Developing within 36 Hours of Birth
Published reports of neonatal tetany contain very few cases showing signs of hypocalcaemic tetany within a few hours of birth. This article presents the findings in 26 infants who developed hypocalcemic tetany from 40 minutes to 36 hours after birth. The clinical material includes a high proportion of infants born prematurely, a number born to diabetic mothers, several twins, and four who had received exchange transfusions. Hypocalcemic tetany is defined as abnormal neuromuscular hyperexcitability associated with a concentration of calcium in the serum of 8 mg/100 ml or less. Complete recovery occurred quickly in all cases. It was found necessary to administer calcium therapy to only a few and in these the response appeared to be erratic. It is pointed out that a clear distinction cannot be made between exaggeration of the physiologic hypocalcemia of the newborn and a definite pathologic hypocalcemia. In other words, the hypocalcemic tetany occurring within the first 36 hours of life may be regarded as an exaggeration of a normal physiologic state rather than as a distinct abnormal biochemical entity. It is also pointed out that the level of calcium in the serum may not be the only factor determining the development of clinical manifestations of tetany, but that disturbance of other electrolytes which may affect the excitability of muscle should receive further investigation.
