Effect of glutathione on the cadmium chelation of EDTA in a patient with cadmium intoxication
In order to evaluate the efficiency and renal protective effects of glutathione during Ca++-EDTA chelation therapy for chronic cadmium intoxication, we measured the renal excretion of cadmium, β2-microglobulin, proteinuria, and hematuria during intravenous administration of glutathione with Ca++-EDTA in a 54-year-old patient with chronic cadmium intoxication. We administered 500 mg of Ca++-EDTA and 50 mg/kg of glutathione alone or in 1 L of normal saline over the next 24 hours and repeated this over 12 consecutive days. During the first 3 days, the basal levels (only saline administration) were determined; during the second 3 days, Ca++-EDTA only was administered, for the third sequence of 3 days, Ca++-EDTA with glutathione was provided, and for the last 3 days, glutathione alone was given. One month later, the same protocol was repeated. There were six blood and urine samples to analyze in each group. The blood cadmium level was higher when the EDTA was infused together with glutathione (7.44 ± 0.73 µg/L, p < 0.01) compared to the basal level of 4.6 ± 0.44 µg/L. Also, the renal cadmium excretion was significantly higher in the EDTA with glutathione group than in the basal group (23.4 ± 15.81 µg/g creatinine vs 89.23 ± 58.52 µg/g creatinine, p < 0.01). There was no difference in the protein/creatinine and β2-microglobulin/creatinine ratio in the urine (p > 0.05) among the groups. Furthermore, microhematuria and proteinuria did not develop over the observation period of 6 months. These results suggest that glutathione administration with EDTA might be an effective treatment modality for patients with cadmium intoxication.