Chromatolysis in alcoholic encephalopathies. Pellagra-like changes in 22 cases.

In 22 patients with alcoholic encephalopathies, chromatolysis similar to that reported in endemic pellagra was found on postmortem examination. No gross macroscopic changes were seen in affected areas and only neurons were involved. The changes consisted of central chromatolysis, seen predominantly in the brainstem, especially in the pontine nuclei, where they were constant, and in the cerebellar dentate nuclei. Nuclei of cranial nerves (mainly the third, sixth, seventh and eighty), the reticular nuclei, arcuate nuclei and posterior horn cells, were also markedly affected. Changes were sometimes seen in the cerebral cortex, the interpeduncular nuclei, the central mesencephalic grey matter, the colliculi, the tenth and twelfth cranial nerve and perihypoglossal nuclei, the gracile and cuneate nuclei and anterior horn cells. This distribution was different from that reported in endemic and 'endogenous' pellagra or in isoniazid-induced pellagra encephalopathy. Central chromatolysis was the only pertinent finding of the CNS examination in 9 cases. In 8 cases, chromatolysis was associated with Marchiafava-Bignami encephalopathy, in 4 cases with Wernicke-Korsakoff encephalopathy, and in 1 other case with both. Mild degeneration of spinal cord tracts was seen in 3 cases. The chromatolysis of alcoholic pellagra did not appear to be a retrograde change related to axonal degeneration. Systemic examination showed liver changes in 15/16 cases. Treatment of these cases had not included niacin. No differences were found between cases given thiamine and pyridoxine and those which had not. Microscopic examination of the pons is essential in alcoholic encephalopathies.