Latent tetany and anxiety, marginal magnesium deficit, and normocalcemia.

The identification of marginal magnesium deficit, such as we have detected in a patient with anxiety, depression, and psychomatic complaints, is a difficult diagnostic problem. Electromyography of a limb, rendered acutely ischemic either just before or after hyperventilation, can elicit latent tetany in this condition, as well as in calcium deficiency. We have demonstrated iterative electrical activity in our patient, whose magnesium deficit is attributable to renal wasting of magnesium. We have elicited similar patterns in several other patients, who had marginally low serum magnesium and who also exhibited weakness, anxiety, and psychosomatic disorders. This preliminary report suggests the need for further consideration of the possibility that chronic magnesium-deficit may contribute to the syndrome of latent tetany, psychosomatic complaints, and weakness.