374 TYPHOID FEVER 



extent, the whole mesentery being filled with glandular masses. 

 In such glands there may be acute inflammation, and occasion- 

 ally necrosis in patches occurs. Sometimes on section the 

 glands are of a pale-yellowish colour, the contents being diffluent 

 and consisting largely of leucocytes. Typhoid bacilli may be 

 isolated both from the glands and the lymphatics connected with 

 them, but the b. coli is in addition often present. 



The spleen is enlarged, on section usually of a fairly firm 

 consistence, of a reddish-pink colour, and in a state of conges- 

 tion. Of all the solid organs it usually contains the bacilli in 

 greatest numbers. They can be seen in sections, occurring in 

 clumps between the cells, there being no evidence of local 

 reaction round them (Fig. 110). Similar clumps may occur in 

 the liver in any situation, and without any local reaction. In 

 this organ, however, there are often small foci of leucocytic 

 infiltration, in which, so far as our experience goes, bacilli 

 cannot be demonstrated. The bacillus is found, often in large 

 numbers, in the gall-bladder, in which situation in cases which 

 recover it may persist for years (vide infra). Clumps of bacilli 

 may also occur in the kidney. 



In addition to these local changes in the solid organs, there are also 

 widespread cellular degenerations in the solid organs which suggest the 

 action of toxic products. 



In the lungs there may be bronchitis, patches of congestion and of 

 acute broncho-pneumonia. In these, typhoid bacilli may sometimes he 

 observed, but evidence of a toxic action depressing the powers of resist- 

 ance of the lung tissue is found in the fact that the pneumococcus 

 frequently occurs in such complications of typhoid fever. 



The nervous system shows little change, though meningitis associated 

 either with the typhoid bacillus, with the b. coli, or with the strepto- 

 coccus pyogenes has been observed. 



In typhoid fever the bacilli can in 90 per cent, of cases be isolated from 

 the blood during the course of the illness. The local lesions are thus associ- 

 ated with a general septicsemic process. The bacilli have been found in 

 the roseolar spots which occur in typhoid fever, but it cannot be yet 

 stated that such spots are always due to the presence of the bacilli. The 

 fact that the typhoid bacilli are usually confined to certain organs and 

 tissues shows that they probably have a selective action. 



To sum up the pathology of typhoid fever, we have in it a 

 disease the centre of which lies in the lymphoid tissue in and 

 connected with the intestine. In this situation we must have 

 an irritant, against which the inflammatory reaction is set up, 

 and which in the intestine is sufficiently powerful to cause 

 necrosis. The affections of the other organs of the body suggest 

 the circulation in the blood of poisonous substances capable of 

 depressing cellular vitality, and producing histological changes. 



