Dialysis Disequilibrium syndrome: a neurological manifestation of haemodialysis

Renal insufficiency has many protean effects on the central nervous system. Early symptoms such as fatigue, clumsiness, and impaired concentration may progress to hallucinations, agitation, disorientation and coma if the renal insufficiency is untreated. The pathophysiology of these changes, due to uraemic encephalopathy are thought to be mediated by impaired neurotransmission (Burn & Bates, 1998). Dialysis of patients with end-stage renal disease (ESRD) helps to minimize the effects of uraemic encephalopathy. However, dialysis of uraemic patients may in itself, also have deleterious effects on the nervous system. One of the potential neurologic sequelae of this treatment modality is dialysis disequilibrium syndrome. First described in 1962, the dialysis disequilibrium syndrome (DDS) is a central nervous system disorder that remains an important clinical problem in dialysis patients. It is characterized by neurologic symptoms of varying severity that are thought to be due primarily to cerebral oedema. Classically, DDS arises in individuals starting haemodialysis due to chronic renal failure and is associated, in particular, with “aggressive” (high solute removal) dialysis (Port et al., 1973).