Abstract
A total of 166 maintenance dialysis patients were separated among 4 groups according to the duration of their dialysis; Group A: more then 10, B: more then 5 and less than 10, C: more than 1 and less than 5 and D: less than 1 year. Renal osteodystrophy (ROD) in those patients was observed periodically by microdensitometry, and the bone index (BI) was calculated based upon metacarpal index and bone mineral content thus obtained. In addition, the plasma levels of aluminum were measured prior to and after administration of desferrioxamine, intact PTH (i-PTH), active vitamin D3 and other treatment.
As the duration of dialysis increased, the BI worsened. Compared to groups A and B, group C demonstrated a sinilarly rapid progress in ROD in 5 years. The level of active vitamin D3 was low in all 4 groups. The i-PTH, though normal in group C, tended to increase linearly with the duration of dialysis. Aluminum in plasma was high even in the initial phase and the degree of increase in aluminum with the infusion of desferrioxamine was positively correlated with the duration of dialysis.
Based upon these observations, it is concluded that osteomalacia exists even in the initial phase due to deficiency of active vitamin D3 and to the aluminum accumulation and that prolonged dialysis also causes osteitis fibrosa and gradually increased i-PTH.
