Bone disease in patients on maintenance haemodialysis using softened or de-ionized water

A clinical, biochemical and radiological study was carried out in 28 patients on maintenance haemodialysis in order to assess the prevalence of bone disease, particularly with regard to osteomalacia and/or osteopenia. The patients were selected from dialysis units using softened or deionized water, and the aluminium levels measured in the different water supplies. The results showed that symptomatic osteomalacia/osteopenia occurs more frequently in the units using softened water, which has a higher aluminium content, than in the de-ionized water unit. The patients dialysed on softened water also have significantly higher serum calcium and phosphorus levels. It is suggested that in Johannesburg, water softening alone is inadequate, and that the high aluminium levels in our water may be responsible for accelerated osteomalacia/osteopenia.