ENTRANCE AND SPREAD OF BACTERIA. 



195 



:i-r 



children have been described in which the bacillus pyocyaneus 

 has been found throughout the body ; in these cases the chief 

 symptoms have been fever, gastro-intestinal irritation, pustular 

 or petechial eruptions on the skin, and general marasmus. 



Suppurative and inflammatory conditions, associated with 

 the organisms of special diseases, will be described in the respec- 

 tive chapters. 



Mode of Entrance and Spread. — Many of the organisms of 

 suppuration have a wide distribution in nature, and many also 

 are present on 



the skin and mu- _ ■'.,'. -^ f. y- J ■:. '■. 



cous membranes 

 of healthy indi- 

 viduals. Staphy- 

 lococci are com- 

 monly present 

 on the skin, and 

 also occur in the 

 throat and other 

 parts, and strep- 

 tococci can often 

 be cultivated 

 from the secre- 

 tions- of the 

 mouth in normal 

 conditions. The 



a 



Fig. 73. — Minule focus ot coinniencing suppuration in 

 brain — case of acute ulcerative endocarditis. In the centre a 

 small haemorrhage; to right side dark masses of staphylococci; 

 zone of leucocytes at periphery. 



Alum carmine and Gram's method. X 50. 



pneumococcus 

 of Fraenkel and 

 the pneumoba- 

 cillus of Fried- 

 lander have also 



been found in the mouth and in the nasal cavity, whilst the 

 bacillus coli communis is a normal inhabitant of the intestinal 

 tract. The entrance of these organisms into the deeper tissues 

 when a surface lesion occurs can be readily understood. Their 

 action will, of course, be favoured by any depressed condition 

 of vitality. Though in normal conditions the blood is bac- 

 terium-free, we must suppose that from time to time a certain 

 number of such organisms gain entrance to it from trifling 

 lesions of the skin or mucous surfaces, the possibilities of 



