Progressive myoclonic encephalopathy in dialysis patients. Clinical, electroencephalographic and neuropathological study. Pathogenetic discussion

Clinical and Neuropathological data on sixteen cases of progressive myoclonic encephalopathy are reported. This neurological syndrome appears after an average duration of thirty two months of haemodialysis and leads to death in four and a half months, and is characterized by myoclonus, speech disorder, epileptic seizures, and mental-status changes. At first, clinical signs and symptoms are related to haemodialysis, later they become permanent. An early diagnosis is based on EEG which is the only useful laboratory test, demonstrating bisynchronous slow-wave bursts. The caracteristic histopathologic findings are neuronal depopulation, lipofuscin accumulation, and appearance of Neurofibrillary degeneration, especially in Motor cortex, red nucleus and dentato-olivary systems. It seems to be justified to attribute P.M.D.E. to aluminium chronic poisonning; the source of the aluminium intoxication is not aluminium containing phosphate-binding gels but intravenously administreted tape-water. The intracellular binding of aluminium is shown from a histochemical study employing fluorescent stain Morin.