THE DIGESTIVE SYSTEM. 561 



THE CAECUM. 



Catarrhal Inflammation of the caecum is not uucommon. It is usually 

 produced by an habitual accumulation of faeces in this part of the intes- 

 tine. The course of the inflammation is usually chronic, but marked by 

 acute exacerbations. At first the mucous membrane undergoes the ordi- 

 nary changes of chronic catarrhal inflammation. To this may succeed a 

 slow suppurative inflammation which extends through the wall of the 

 intestine and gives rise to ulcers and perforations. 



Through these perforations the faeces may pass into the peritoneal 

 cavity, or the perforations are partly closed by adhesions, and abscesses 

 are formed, or sinuses into the surrounding soft parts. 



Chronic Hyperplastic Tuberculosis of the Heo-caecal Region and Other Parts 

 of the Intestine. Attention has recently been called to a peculiar form of 

 tuberculous inflammation of the intestine which is characterized by the 

 extensive formation of small spheroidal -celled and fibrous tissue, espe- 

 cially in the submucosa and often involving the muscular wall and the 

 subserous layer. Miliary tubercles, cheesy degeneration, and ulcera- 

 tion are not usually conspicuous features of the lesion. The ileo-caecal 

 region is most often involved, the rectum less frequently, while the lesion 

 is rarely limited to the ileum. Both the large and small intestine may 

 be involved together. The new tissue may form a circumscribed annular 

 thickening of the wall of the gut, or it may occur as a distinct tumor or 

 as polypoid projections of the mucous membrane. The intestine in the 

 vicinity of the involved portion may be enclosed in a mass of fibrous fat 

 tissue. Owing to the thickening of the wall of the intestine the lumen 

 may be much narrowed or nearly completely stenosed. On section of the 

 thickened areas, caseous foci may be revealed ; ulcerations, in rare cases, 

 may be absent ; more often they are moderate or extensive. 



The microscopical examination shows that while iniliary tubercles and 

 cheesy degeneration are commonly to be detected, the new tissue consists 

 in the main of collections of small spheroidal cells with more or less 

 fibrous stroma and occasionally giant cells and of moderately cellular or 

 dense fibrous tissue. The polyhedral cells common in tuberculous in- 

 flammation are not as a rule conspicuous. The new tissue is usually 

 most abundant in the submucosa. The mucosa may be similarly thick- 

 ened, usually in polypoid form, or unchanged ; it may show simple ca- 

 tarrhal alterations or may contain miliary tubercles or be ulcerated. The 

 muscular coat may be also infiltrated and much thickened' by the new- 

 formed cellular and fibrous tissue and there may be muscular hyper- 

 trophy. The associated lyniph -nodes maybe involved. Tubercle bacilli 

 are present in the lesions, sometimes in enormous numbers. The process 

 appears to be sometimes primary in the intestine ; sometimes it occurs 

 with or follows tuberculous lesions of the lungs. Hyperplastic tubercu- 

 lous lesions limited to the caecum have frequently been operated upon 

 36 



