Ratzmann GW¹, Schmidt F¹

¹ MagiP-Project Greifswald

A positive VON BONSDORFF test (VBT) is generally accepted for clinical evidence of latent tetany (LT). In the VBT the sensibility against classically ischemic induction of TROUSSEAU’s phenomenon is enhanced by following hyperventilation (HV); in positive case leading to manifestation of tetany in subjects suffering from LT. If LT is the main and basal clinical state in human magnesium deficiency syndrome (MD), a positive VBT becomes a high diagnostic position for clinical evaluation of a MD. However, up to date there are no investi-gations on the importance of actual environmental blood milieu for manifestation of provoked tetany during VBT.

We present here results of paraclinical data of patients with functional disturbances during VBT. The basal mean values of groups with positive (pR; n=20) and negative response (nR; n=19) do not show significant differences both for magnesium, calcium, other biochemical parameters, and basal state of acid-base status (SBS). The HV induced SBS changes during VBT of both groups were in a comparable range significantly, in part even more in nR. - In contrast to this it is of interest that after HV the QoTc- and QeTc intervals of the ECG’s were significantly prolonged only in pR alone. – The last, perhaps, reflect a possible greater importance of transmembranal and intracellular conditions for interpreting the provoked tetany response by VBT than blood milieu deviations alone. A positive VBT response is clinically evident for LT, but should not be over- or misinterpreted for a MD, however.