158 DISEASES OF THE STOMACH 



where the stomach tissue is destroyed an oval or round 

 opening or depression with irregular margins appears. The 

 more chronic the process the greater the irregularity in 

 outline. 



Etiology.— Simple ulceration of the stomach, is due to a 

 destruction of the gastric epithelium caused chiefly by a dis- 

 turbance in blood circulation in the stomach and hyperacidity 

 of the gastric juice. It is often brought about by inflammation 

 of the mucosa or hemorrhages, resulting from poisonous sub- 

 stances, caustics, drugs (when administered in too concentrated 

 form); sharp foreign bodies; during the course of infectious 

 diseases (distemper, etc.), or from an invasion by the Bacillus 

 necrophorus (puppies and kittens), or other local- infections. 

 General infection (pyemia) may too be a causative factor. 

 These infections produce an extensive inflammation of the 

 mucosa, often leading to a disturbance in the circulation, 

 interfering with nutrition, and ultimately leading to an ulcera- 

 tive process. Wounds of the mucous membrane from external 

 violence, partial rupture of the stomach walls or parasitic 

 invasion are causes. They are often contributory to the 

 beginning of the ulcerative process. Embolism is also a cause, 

 producing infarcts in the mucosa and submucous tissue. 

 Hemorrhagic erosions and hemorrhages occurring and 

 associated with chronic diseases of the heart, liver or kidneys 

 are probable causes. Hyperacidity may produce gastric 

 ulcer when from any cause the mucous membrane is injured, 

 the acid acting upon the ends of exposed vessels by contract- 

 ing them, thus inducing local anemia and eventually necrosis. 



Pathology.— The typical ulcer is round or oval, extending 

 more or less deeply into the mucous membrane or the wall 

 of the stomach. They have a characteristic funnel shape, 

 and when acute form a rather regular outline, while in ulcers 

 of long standing the margins become very irregular. When 

 chronic ulcers are present, the entire wall is usually thickened. 

 Sometimes a coalescence of the ulcerations or erosions occurs. 

 When ulceration becomes severe and the submucosa is 

 involved, adhesions exist with adjacent organs. 



Symptoms.— In quite a large percentage of cases of mild 

 ulceration or erosions the symptoms are never observed 



