202 THE INFECTIOUS DISEASES. 



form deeply staining, irregular clumps or masses, or may disintegrate 

 (Fig. 93). 



Associated with or following these changes there may be a gathering 

 of leucocytes about and within these necrotic areas, so that the foci may 

 present the appearance of little abscesses or masses of lymphoid tissue. 

 Finally, these necrotic areas may undergo repair and be replaced by 

 small, spheroidal, young connective-tissue cells, granulation tissue, or 

 finally by small masses of cicatricial tissue. 1 



Septicaemia and Pyaemia. Bacteria as well as their toxins may be 

 distributed from a local portal of entry or an infected region throughout 

 the body, not only inciting general functional and structural changes, 



I. . 



-....- - ... ~ 



FIG. 93. FOCAL NECROSIS IN THE LIVER INDUCED BY Toxic MATERIAL OF BACTERIAL ORIGIN. 



but when the bacteria lodge in various situations giving rise by new local 

 proliferation to fresh foci of inflammation. 



It is customary to designate the condition in which bacteria as well 

 as their toxins are distributed through the body by the blood and lymph 

 channels as xrptjcamia. Wtie.n fregh supp_uratiye foci develop as the re- 

 sult f this distribution, the condition is called gy&wia. 



The terms septicaemia and pyaemia are survivals of a nomenclature 

 adapted to the period before the nature of the excitants of infectious 

 disease was definitely known. The manifestations of septicaemia were 

 then attributed to the presence of putrid material in the blood. Pyaemia 

 expressed the belief that the lesions characterizing this condition were 

 due to the presence of pus in the blood. The term bactericemia is some- 

 times and more correctly used to indicate the presence of bacteria in the 

 blood, but the old words with their new implications and limitations are 

 still commonly employed. 2 



1 For a comprehensive study of focal necrosis and other associated lesions in certain 

 forms of toxremia, consult the excellent study of Flexner, "The Pathology of Toxalbu- 

 min Intoxication," Johns Hopkins Hospital Reports, vol. vi., p. 259, 1897, Bibl. 



2 It has long been known that persons who have received injuries or wounds may 

 suffer from constitutional symptoms, among the most marked of which may be fever, 

 and develop local or disseminated lesions. To designate the condition of these patients 



