Lewy Body Dementia: Discovery by Friedrich Lewy and Historical Context

Friedrich Lewy (1885–1950)

German-born neurologist/psychiatrist. Worked with Alois Alzheimer in Munich. In 1912, while examining brains of Parkinson’s disease patients, he described intraneuronal eosinophilic inclusions in the dorsal vagal nucleus, basal nucleus of Meynert, and other brainstem nuclei.

Key Discoveries

• Inclusions: spherical, eosinophilic, displacing nucleus – named Lewy bodies (by Köster, 1920s).
• Composed of aggregated α-synuclein (identified 1997, Spillantini et al.).
• Also found in dementia with Lewy bodies (DLB), multiple system atrophy (MSA), and incidental Lewy body disease.

From Pathology to Clinical Syndrome

• 1961: Okazaki – cortical Lewy bodies in dementia cases.
• 1984: Kosaka – “diffuse Lewy body disease” clinical criteria.
• 1995: First consensus criteria for DLB (McKeith).
• 2005/2017: Updated DLB criteria (core features: fluctuating cognition, visual hallucinations, REM sleep behavior disorder, parkinsonism).
• Now recognized as 2nd most common neurodegenerative dementia after Alzheimer’s (~15–20% of cases).

Lewy’s Legacy

Fled Nazi Germany (1934) → USA. Worked at U. Penn, Haverford College. Continued research on paralysis agitans, inclusion bodies. His meticulous neuropathology laid groundwork for α-synucleinopathy field.

Clinical Pearl

Lewy bodies in brainstem = Parkinson’s; Lewy bodies in cortex + brainstem = DLB. Same protein, different topography → different phenotypes. Both are synucleinopathies.