SERUM ALUMINUM TRANSPORT AND ALUMINUM UPTAKE IN CHRONIC-RENAL-FAILURE- ROLE OF IRON AND ALUMINUM METABOLISM

Several factors have been blamed for increasing gastrointestinal absor ption of aluminum. The likely role of iron metabolism was suggested so me years ago. As iron and aluminum share many chemical properties, it is reasonable to think they also share biological pathways. The aim of this study was: (a) to evaluate serum aluminum transport and its rela tionship with iron-binding capacity, and (b) to investigate aluminum h ydroxide absorption as a function of iron and aluminum. We investigate d 127 patients with chronic renal failure undergoing hemodialysis in a study divided into two phases: phase 1, a basal study to investigate serum iron and aluminum status, and phase 2 in which an aluminum absor ption test was performed. In phase 1, we found that the lower basal se rum iron and iron transferrin saturation the greater serum aluminum (p < 0.001). In phase 2, we found a negative relationship between serum aluminum increments after the test and basal levels of serum aluminum and iron (r = -0.70; p < 0.001). These results suggest that the amount of either aluminum or iron carried by transferrin may influence the t ransferrin capacity to bind the other element and also may modulate, t ogether with other factors, the gastrointestinal absorption of iron an d aluminum.