Centenary of Tretiakoff's thesis on the morphology of Parkinson's disease, evolved on the grounds of encephalitis lethargica pathology.

In his Thèse de Paris (1919) Konstantin Tretiakoff (1892-1956) described the two main morphological lesions in Parkinson's disease: the loss of pigmented nerve cells in the Substantia nigra and the intracellular inclusion bodies in idiopathic paralysis agitans, calling them "Corps de Lewy," which already had been described by F. H. Lewy in 1912. Tretiakoff's findings on idiopathic Parkinson's disease were confirmed years later by Rolf Hassler in his dissertation on anatomy and pathology of Substantia nigra in Berlin (1938, 1939). German authors in the 1920s underestimated the significance of both findings (Bielschowsky, 1922; Lewy 1923/1924; Spatz 1927), especially Lewy himself. Lewy (1923) and other German neurologists and neuropathologists like Felix Stern (1922, 1928), Goldstein (1922), and Spatz (1927; Luksch & Spatz, 1923) acknowledged the typical Nigra-lesions only for postencephalitic Parkinsonism. It is argued that Tretiakoff's selective attention for the Substantia nigra was guided by the frequency of epidemic encephalitis lethargica and its preponderance of nigral pathology. This impression can be derived from Tretiakoff's early paper on that disease (Marie & Tretiakoff, 1918) and from Paul Foley's opus magnum (2018). Two outstanding neurologists dedicated to this issue are called into memory: Gabrielle Lévy, the successor of Tretiakoff in the Salpêtrière laboratory, and Felix Stern, who died in 1942 as a victim of Nazi terror. The eponym Lewy-bodies went back to Lafora and Tretiakoff ("Corps de Lewy"). Newly expressed doubts about Lewy's primacy or Lafora's credit for the eponym (Lafora-bodies since 1911) can be refuted with the studies of Greenfield and Bosanquet (1953) and Greenfield (1963) by illustrating their different staining properties.