330 THE ALCALIGENES DYSENTERY TYPHOID 



site of the ulcer marked by a somewhat depressed cicatrix. Occasion- 

 ally secondary infection of the ulcers results in perforation or hemor- 

 rhage, and sometimes an uninfected ulcer may erode through a 

 blood vessel, causing hemorrhage. It should be remembered that 

 typhoid ulcers tend to run along the long axis of the intestine, whereas 

 tuberculous ulcers, on the contrary, run transversely, following the 

 course of the lymphatics. 



In addition to the intestinal lesions, there is in typhoid fever an 

 acute splenic tumor with a great proliferation of typhoid bacilli in 

 this organ. Foci of typhoid bacilli are commonly found also in the 

 kidneys and the liver, mesenteric lymph nodes, less commonlv in 

 lungs, meninges, bone marrow, certain muscles and the tonsils. Paren- 

 chymatous degeneration of the heart, liver and kidneys is common, 

 as is a catarrhal inflammation of the respiratory tract and a severe 

 inflammation of the entire intestinal mucous membrane. Somewhat 

 uncommonly, typhoid cases have been recorded in which there are no 

 intestinal lesions. In these cases it would appear that the disease is 

 septicemic in character. 1 In typhoid fever there is leucopenia, due 

 apparently to some interference with the activity of the bone marrow. 

 The febrile reaction is usually attributed to the liberation of endotoxin 

 from typhoid bacilli, which are dissolved in the blood stream by 

 specific lysins. This toxin exhibits both a general and local reaction. 

 The general reaction is characterized chiefly by fever and symptoms 

 of generalized toxemia; the local reaction is particularly marked in 

 those areas where typhoid bacilli undergo solution, as in the spleen 

 and Peyer's patches. 



Various complications of typhoid fever are occasionally reported, 

 caused by the localization of typhoid bacilli either alone or in 

 association with other bacteria, as the streptococcus, staphylococcus, 

 or pneumococcus, in various organs. Peritonitis, usually following 

 perforation of an ulcer in the intestinal wall, is one of the most severe 

 of these complications. Abscess formation in various deep-seated 

 organs, as the spleen and psoas muscle, is not uncommon. Broncho- 

 pneumonia, pleurisy, pericarditis, osteitis, and inflammation of the 

 membranes of the cord (meningitis) and brain have also been attributed 

 to the typhoid bacillus. 



Carriers. Typhoid bacilli can not be isolated from the majority 

 of typhoid patients after the fifth week of the disease. In a small 



1 Possett, Atypische Typhusinfektion. Lubarsch and Ostertag, Ergebn. d. allgem. 

 Pathol., 1912, xvi, 184. 



