DIPHTHERITIC DYSENTERY. — An in flammatory disease of variable and un certain etiology, which affects especially the large intestine, sometimes involving the small gut, which may or may not be attended with fever; is characterized by mucous, serous, or bloody stools, and is accompanied with tormina and tenesmus. The anatomical lesions consist of necrosis of the mucous membrane, the deposit within its substance and upon its surface of a fibrinous psendomembrane, and the formation of ulcers. This occurs (a) as a primary disease, in which form it prob ably gives rise to the great majority of the cases of epidemic dysentery; (b) a secondary and terminal affection in many acute and chronic diseases, the chief ones being acute general infections and chronic renal, cardiac, and hepatic disease. Certain cases of sporadic dysen tery, the result of the action of chemicals and metastatic bacteria upon the intes tinal mucous membrane and indirectly of mechanical irritants (coprostasis, in testinal worms), belong to this class.
Morbid Anatomy and Eliology.—The pathological process begins with hyper iemia and swelling of the submucosa and mucosa. The unique character of the dis ease begins with the appearance of small grayish-white membranous patches upon the surface of the mucous meinbrane. These increase in size and become con fluent. At first they are readily removed with the finger; at a later stage they are more adherent. They tend to appear, by preference, upon the more prominent and projecting parts of the mucosa; thus, in the small intestine along the tips of the valvuhe conniventes; in the large, corresponding with the insertion of the longitudinal muscular bands. At a later time and in severe cases the intervening mucous membrane may become covered. Upon microscopical examination, in the earliest stages of the disease the blood vessels of the submucous and mucous coats are congested and contain an in creased number of polymorphonuclear leucocytes; the superficial epithelial layer is necrotic, and fibrin and leuco cytes are present on the injured surface. Somewhat later the necrosis has ex tended and involved the deeper parts— glands and interglandular tissue—and the fibrinous membrane is thicker and intimately bound up with the necrotic tissue. Many kinds of bacteria are pres
ent in the necrotic and exudative ma terial. The swelling of the submucosa may reach a high degree, due to cedema, cellular infiltration, and a deposit of fibrin. The blood-vessels of the mucous membrane become plugged by hyaline thrombi. The separation of the dead tissne leaves an ulcer behind. The young ulcers do not extend deeper than the submucosa coat; later, and by continued destruction, the muscular coat may be exposed. Perforation of the intestines is, in this form of dysentery, unusual. Ecchymoses occur in the neighboring mucosa. Even the deepest ulcer may, throngh the formation of granulation tissue, heal. In these cases the wall of the intestine becomes thickened; the muscle hypertrophic; the scars have a pigmented appearance, and, through re traction of the cicatricial tissue, de formity and often stenosis of the bowel arise.
The points of predilection of the path ological process are the flexures (sigmoid, splenic, hepatic), the ascending colon, and cfecum. In the Crimean War the rectum, sigmoid flexure, and descending • colon were the principal points of attack. The small intestine is only rarely affected in its lowest parts, and this in severe cases; in certain secondary forms of dys entery it may be attacked alone.
Klebs was the first to describe short bacilli in the crypts of Lieberkuhn in diphtheritic dysentery. Since this time a large number of bacteria have been described in association with the disease. None of these appear to be specific, and the circumstances of the disease make it easy to isolate different bacterial forms. From what has already been said it is not probable that diphtheritic dysentery is caused by a single micro-organism. As regards the question of etiology of epidemics, whether in a given epidemic a single species of micro-organism is to be regarded as the cause, and in different and widely-removed ones tbe same spe cies will be found, cannot be answered at present. Thus far a very small num ber of epidemics have been studied with modern bacteriological methods.