Malformations are occasionally met with. The omentum may be very small or unduly long. The mesentery may be very long, giving rise to enteroptosis. May allow hernias.

Circulatory Disturbances

Active hyperemia, either localized or diffuse, is present during the early stage of inflammation, and is also met with in relation to tubercles and neoplasms. Passive hyperemia follows obstruction to the portal circulation. The veins may become much distended and tortuous and small hemorrhages into the subperitoneal tissue may be present.

Hemorrhage beneath the peritoneum in the form of petechias and irregular streaks is found in chronic passive congestion, in asphyxia, in phosphorous poisoning, and in some infections.

Hemorrhage into the peritoneal cavity results from rupture of a blood-vessel. When as a consequence of traumatism any of the internal viscera, as spleen or liver, rupture, blood will be present. Is also found in cases of rupture of abdominal aneurysms, and of extra-uterine pregnancy and, from typhoid or other perforations.

The blood collects in the dependent portion of the abdomen and may coagulate or remain fluid. If the patient recovers, the blood may be absorbed without any permanent changes, although adhesions sometimes form.

Ascites or a collection of serous fluid within the peritoneal cavity is frequently seen. It may be due to obstruction of the portal circulation, especially in atrophic cirrhosis of the liver or as a part of a general dropsical condition in cardiac and renal disease.

It is also found in some local diseases of the peritoneum, as tuberculosis, etc.

The ascitic fluid is generally clear, straw-colored, specific gravity 1008 to 1015, with a small amount of albumin, which rarely coagulates spontaneously. The amount may vary from a few cubic centimeters to several liters and may become so great as to cause marked inconvenience by distending the abdominal cavity and by pushing the diaphragm upward. This latter may cause extreme dyspnea. If the fluid is removed, it frequently collects again and again. If adhesions have formed, there may be localized collections of fluid.

If there has been obstruction to the thoracic duct, the ascitic fluid is frequently milky in character, due to the presence of chyle (chylous ascites). This fluid contains fat droplets as well as the red and white cells that are ordinarily present, and endothelial cells from the peritoneum.

Sometimes there may be a collection of fluid between the layers of the omentum.

When the ascites has existed for a long time there is nearly always a secondary chronic inflammation of the peritoneum with thickening.

Peritonitis, inflammation of the peritoneum, may be primary or secondary. This serous membrane covers such a large surface and so readily absorbs fluids that infection may take place with comparative ease.

Primary or idiopathic acute peritonitis arises through the infecting agent being carried by the blood from a pyogenic focus in some distant part of the body.

Secondary acute peritonitis is the more common form. It follows local injury to the peritoneum, as a result of injury or disease, the infecting agent being carried generally by the lymphatics.

Peritonitis is brought about by infectious inflammations of neighboring tissues, particularly in septic conditions of the female genital organs, by perforations of the stomach or intestines, by appendicitis, by strangulation of the bowels, etc.

According to the extent of the lesion the peritonitis may be localized or general. The severity of the disease also differs greatly.

The membrane at the point of infection is at first hyperemic, is dull, and a serous or serofibrinous exudation soon appears. This rapidly becomes purulent or may have been so from the beginning. If the process has not been a very rapid one the affected area will be covered by a thick whitisli or creamy layer of fibrin. As the exudate increases in quantity it collects in localized pockets among the coils of intestine. The fibrin may undergo organization, adhesions form between the loops of the intestine, the omentum, the abdominal walls, and other organs, and the purulent matter be surrounded and walled off. It may be absorbed, infiltrated with lime salts, or replaced by fibrous tissue. The pus may burrow and empty either externally or into some hollow organ. If the adhesions have not been sufficiently dense, the abscess may break through and infect the greater part of the peritoneum. In such a severe form the serous membrane becomes infiltrated and partially disorganized.

Localized peritonitis is not usually fatal, but in the general form recovery is rare. When peritonitis subsides and the individual lives, adhesions of varying extent remain. These eventually become transformed into dense fibrous bands that may cause very severe trouble by binding the coils of intestine together or by so compressing them that the bowel becomes more or less obstructed.

As a result of the acute inflammation the peristaltic action of the intestines is at first stopped by spasmodic contractions. In a very short time the muscle fibers become paralyzed and there is then almost complete cessation of motion. General septicemia may follow the peritonitis.

In the newborn, peritonitis generally follows septic infection of the umbilical cord.

Chronic Peritonitis

Chronic Peritonitis may follow in the course of acute peritonitis, particularly if it were localized or it may occur independently. When encapsulated collections of pus have failed to be absorbed the peritoneum adjacent shows marked chronic thickening. The omentum is frequently shortened and rolled up. A serous or other exudate may be present. Local thickenings may also be due to chronic disease of the underlying organ. This is particularly the case at times on the liver and spleen. The membrane becomes very thick, white and smooth, and resembles icing of a cake, the so-called "Zuckerguss" organs. Chronic peritonitis is particularly common in the neighborhood of the female genitalia; all of which, uterus, tubes, and ovaries, may be united by dense bands of connective tissue. Is also always present in tuberculosis of the peritoneum.

Tuberculosis Of The Peritoneum

Tuberculosis Of The Peritoneum is seldom primary, but is commonly found as a secondary lesion in similar disease of the intestine, or mesenteric lymph-nodes. The condition may be local, being limited to the peritoneal surface of the intestine overlying tuberculous ulcers; or it may be widely disseminated as a general miliary involvement. The lesions may coalesce and form large caseous areas or there may be extensive connective-tissue formation with adhesions causing the intestines to be bound together in one dense mass. Occasionally there may be considerable serous exudate present; if the exudate is purulent it generally indicates that there has been a secondary infection by pus-producing organisms. The exudate may at times be completely absorbed or remain as sacculated collections. The tubercles may heal by granulation and cicatrization and the individual get well.

The mesenteric lymph-nodes are generally enlarged and caseous.


Primary tumors are unusual, new growths being generally metastatic or the result of direct extension. Fibroma and lipoma are sometimes seen. Sarcoma is rare.

Endotheliomata are quite frequently found, originating probably from the endothelium of the subperitoneal lymph channels and not from the flat cells lining the peritoneum. As a rule they do not occur as localized growths but are distributed throughout the peritoneum, giving somewhat the appearance of tuberculosis. The omentum is probably the seat of the primary growth.

Carcinoma is nearly always secondary, but it is thought that primary carcinoma might arise from fragments of epithelial tissues, from fetal remnants, or from portions of intestine pinched off in fetal life. There is usually a general distribution of tumor nodes of all sizes over the greater part of the peritoneum. When the nodules are widely distributed the condition is known as "carcinomatosis." There is always some inflammatory reaction, so adhesions are quite common. The carcinoma may extend from various abdominal organs, as the uterus, tubes and ovaries, and intestines. A gelatinous or colloid cancer of the stomach or intestine is usually soon followed by a similar growth involving the peritoneum. Such a tumor contains large and small masses of clear colloid material resulting from degeneration of the cells.

Cysts are sometimes encountered, the usual form being due to a dilatation of lymph-vessels.

Parasites are rare, but echinococcus cysts have been found as well as filaria and actinomyces.