174 PATHOLOGY OF TYPHUS IN MAN 



monias (Jour. Exp. Med., Baltimore, 1919, Vol. XXX, JJo. 5, 

 p. 505) caused by the streptococcus and pneumococcus. 



(r) The central nervous system: The lesions of the brain and 

 spinal cord in typhus have been extensively studied by the 

 authors (Ceelen, 1916, Spielmeyer, 1919) cited above. The 

 occurrence throughout the central nervous system of nodules 

 or of tubercle-like lesions, in some way associated with blood 

 vessels, is regarded by all as constant and characteristic. 

 (Plates XX, XXI, and XXV, figs. 49, 50, 51, 52, and 60.) 

 Other lesions not characteristic but constant are perivascular 

 infiltrations with lymphocytes, plasma cells, and macrophages 

 and infiltration of the leptomeninges with similar cells. Nicol, 

 Ceelen, and Spielmeyer have recently (1919) given detailed 

 descriptions of the histological findings in the brain and all 

 of the essential points are well established by their work. 

 Spielmeyer has entered into the most detailed account and in 

 some minor points has arrived at opinions at variance with ours. 



The typhus nodule in the central nervous system is widely 

 distributed, more abundantly in gray matter than in the white. 

 It appears characteristically as a sharply circumscribed lesion 

 the size of a small miliary tubercle; it is without necrosis and 

 composed almost wholly of cells unanimously regarded as 

 neuroglia cells. (Plates XVIII to XXI inclusive.) 



We examined the brains from all of our typhus autopsies, 

 thirty-seven in number. The stages of the disease are shown 

 in Table XVI. 



Owing to the large volume of work undertaken by us, a 

 complete topographical study of the brain was not undertaken. 

 Material, however, was saved as a routine from the following 

 locations : cerebral cortex including frontal, parietal, temporal, 

 and occipital lobes; basal ganglia including the optic thalamus, 

 caudate nucleus, lenticular nucleus, and usually the internal 

 capsule; cerebellum including cortex from the lateral lobes 

 and dentate nucleus; mid-brain usually through the anterior 

 corpora quadrigemina; thepons; and the medulla at the levels 

 of the decussation, the olivary bodies and through the middle 

 of the fourth ventricle. The Gasserian ganglia and pituitary 



