Intracellular Mg++ concentration and electromyographical ischemic test in juvenile headache.

One-hundred-and-twenty-eight young headache outpatients underwent an electromyographical (EMG) ischemic test and determination of Mg++ levels in red and mononuclear blood cells. In migraine patients, with and without aura (MwA and MwoA), Mg++ concentration in the erythrocytes and in mononuclear cells was significantly reduced compared to tension-type headache (TTH) patients and healthy controls (p < 0.0001). The EMG ischemic test was positive in 71% of migraineurs, but only in 9.5% of TTH patients. Low intra-erythrocyte and mononuclear cell levels were evident in 84.3% and 81.2% of migraine patients, respectively; those whose ischemic tests were positive had intra-erythrocyte and mononuclear cell levels of Mg++ below the norm, respectively. However, reduced levels of Mg++ in erythrocytes were found in only two patients with TTH, and in mononuclear cells in one patient with TTH. These data provide further confirmation of the role of Mg++ in determining the status of neuromuscular hyperexcitability in about two-thirds of migraine patients, including childhood and adolescence. They also support the validity of carrying out EMG ischemic testing for distinguishing this condition, which can be corrected with adequate oral Mg++ supplementation and with a possible positive impact on headache.