Senile plaques and tangles in dialysis dementia

Area of Science:

• Neurology
• Nephrology
• Toxicology

Background:

• Dialysis encephalopathy syndrome (DES) is a neurological disorder associated with hemodialysis.
• Alzheimer's disease is characterized by senile plaques and neurofibrillary tangles containing paired helical filaments.
• Aluminum has been implicated in the pathogenesis of both Alzheimer's disease and DES.

Purpose of the Study:

• To investigate the presence of neuropathological changes, specifically senile plaques and neurofibrillary tangles, in the brains of patients treated with hemodialysis.
• To explore the potential role of aluminum in the observed cerebral changes in hemodialysis patients, particularly those with DES.

Main Methods:

• Autopsy examination of brain tissue from 7 patients undergoing hemodialysis.
• Histopathological analysis to identify senile plaques and neurofibrillary tangles.
• Comparison of findings between patients with and without dialysis encephalopathy syndrome (DES).

Main Results:

• Senile plaques and/or neurofibrillary tangles were found in 5 out of 7 hemodialysis patients.
• Three patients with DES and two without DES exhibited these neuropathological changes.
• One case in each group showed plaque density comparable to Alzheimer's disease, but with different distribution.
• Neurofibrillary tangles were generally sparse.

Conclusions:

• The presence of senile plaques and neurofibrillary tangles in hemodialysis patients, including those with DES, supports the hypothesis that aluminum may be an etiological factor in cerebral changes.
• These findings suggest a potential link between aluminum accumulation during hemodialysis and the development of Alzheimer's-like neuropathology.