INFLAMMATION OF THE PERITONAEUM, PERITONITIS. 639 



pneumonia and pleurisy which so frequently occur under the same ci> 

 cumstances. Finally, hi not 'a few cases, peritonitis is the immediate 

 result of an infection, and comes under the same category as the inflam- 

 mations of the skin in exanthematous diseases. This form will be de- 

 scribed when speaking of puerperal fever, and other infectious diseases 

 which are " localized in the peritonaeum." Among the exciting causes 

 of peritonitis are : 



1. Severe contusions and penetrating wounds of the abdomen. 

 Among the surgical operations, paracentesis rarely leads to diffuse 

 peritonitis, operations for hernia do so more frequently, while gastrot- 

 omy always causes it. 



2. In the same way it may be caused by ruptures or perforations 

 of organs covered by the peritonaeum, and the consequent entrance of 

 foreign bodies into the peritoneal sac. Thus perforating ulcer or can- 

 cer of the stomach, ulceration of the vermiform process, or of the 

 ccecum, typhoid or scrofulous ulcers of the intestine, perforation of the 

 gall or urinary bladder, opening of abscesses of the liver or spleen, 

 etc., may cause peritonitis. In all these cases the inflammation usu- 

 ally spreads rapidly over the entire peritonaeum. It is only rarely 

 circumscribed by old attachments, or recent adhesions of the intestines, 

 protecting other parts of the peritonaeum from contact with the escaped 

 substances. 



3. Peritonitis may result from propagation of inflammation from 

 other organs ; the peritonaeum participates in the inflammation of or- 

 gans covered by it, just as often as the pleura does in inflammation of 

 the lungs. Of this nature is the peritonitis in typhlitis stercoracea, 

 strangulated hernia, internal strangulations, rotations, and intussuscep- 

 tions of the intestines. Inflammation often extends from the female 

 sexual organs to the peritonaeum. In the same way hepatitis or sple- 

 nitis may cause peritonitis. In these cases the inflammation is usually 

 circumscribed at first ; and in many cases it remains so during its sub- 

 sequent course ; in others, particularly in those caused by incarcera- 

 tion and similar processes, it becomes diffuse. 



4. As we have already said, peritonitis very rarely occurs in per- 

 sons previously healthy, from catching cold, or from unknown atmos- 

 pheric influences. When it does occur, it is called rheumatic perito- 

 nitis. 



ANATOMICAL APPEARANCES. We shall first speak of the appear- 

 ances in acute diffuse peritonitis. 



At the commencement of this disease the peritonaeum is reddened 

 partly by hyperaemia, partly by the escape of blood into the tissue. 

 But, to discover this redness, it is usually necessary, first, to remove 

 from the peritonaeum the deposits which will be described hereafter. 



