384 TETANUS. 



" idiopathic " tetanus. There is, however, practically no 

 doubt that all such cases are true cases of tetanus, and that 

 in all of them the cause is the B. tetani. The latter has 

 also been found in the bronchial mucous membrane in some 

 cases of the so-called rheumatic tetanus, the cause of which 

 is usually said to be cold. 



The pathological changes found post mortem are not 

 striking. There may be haemorrhages in the muscles which 

 have been the subject of the spasms. These are probably 

 due to mechanical causes. Naturally it is in the nervous 

 system that we look for the most important lesions. Here 

 there is ordinarily a general redness of the grey matter, and 

 the most striking feature is the occurrence of irregular 

 patches of congestion which are not limited particularly 

 to grey or white matter, or to any tract of the latter. 

 These patches are usually best marked in the grey matter 

 of the medulla and pons. Microscopically there is little of 

 a definite nature to be found. There is congestion, and 

 there may be minute haemorrhages in the areas noted by 

 the naked eye. The ganglion cells may show appearances 

 which have been regarded as degenerative in nature, and 

 similar changes have been described in the white matter. 

 The only marked feature is thus a vascular disturbance in 

 the central nervous system, with a possible tendency to . 

 degeneration in its specialised cells. Both of these 

 conditions are probably due to the action of the toxines of 

 the bacillus. In the case of the cellular degenerations the 

 cells have been observed to return to the normal under the 

 curative influence of the antitoxines (v. infra}. In the 

 other organs of the body there are no constant changes. 



We have said that the general distribution of pathogenic 

 bacteria throughout the body is probably a relative pheno- 

 menon, and that bacteria usually found locally may occur 

 generally and vice versa. With regard to the tetanus 

 bacillus it is, however, probably the case that very rarely, if 

 ever, are the organisms found anywhere except in the local 

 lesion. 



(/>) The Artificially-produced Disease. The disease can 



