Peritoneal tuberculosis is a relatively uncommon disease caused by a tuberculosis infection in the lining of the abdomen. It is a type of abdominal tuberculosis that infects the peritoneum, a membrane lining the inside of the abdominal cavity that surrounds the abdominal organs. Tuberculosis is primarily a respiratory illness, but it can infect any area of the body. Like all tuberculosis, peritoneal tuberculosis it is caused primarily by the bacteria Mycobacterium tuberculosis and sometimes by other species of the Mycobacterium genus.
Tuberculous enters the peritoneum by spreading from an infection established elsewhere in the body to the abdominal cavity. The infection most frequently originates in the lungs, where it is called pulmonary tuberculosis, before spreading into the abdominal cavity when the sufferer swallows infected sputum. Tuberculosis infections in nearby organs can also spread to the peritoneum. It can also be the result of bacteria entering the peritoneum through the blood stream or lymph nodes. Mycobacterium tuberculosis can lie latent in the body for long periods of time, so symptoms of peritoneal tuberculosis may not occur until years after the bacteria enters the peritoneum. Most people with Mycobacterium tuberculosis bacteria at any given time are only carriers and do not suffer from the disease, but can start to develop symptoms if their immune response is weakened.
As with other tuberculosis infections, peritoneal tuberculosis causes symptoms such as fever, weakness, and night sweats. Infection of the peritoneum also causes symptoms such as abdominal pain, diarrhea, and feelings of pressure or heaviness in the abdomen. Hematochezia, or blood in stool, is also common. A minority of cases of this type of tuberculosis occur simultaneously with pulmonary tuberculosis, which has symptoms such as chest pain, cough, and the production of bloody phlegm, but most cases do not.
The most common form of peritoneal tuberculosis causes an accumulation of fluid, called ascites, in the cavity between the peritoneum’s two layers, the parietal peritoneum and the visceral peritoneum. These are called wet type infections, in contrast with dry type infections, where this fluid buildup does not occur. Ascites can cause additional symptoms, such as swelling, distension, and shortness of breath. It also creates a risk of further complications, such as inflammation and renal problems.
Peritoneal tuberculosis is rare in the industrialized world, but more common in developing countries. It is treatable with antibiotics, but can be deadly without medical attention. People with immune systems weakened by poor health, the side effects of some drugs, and illnesses such as AIDS that damage the immune system are especially vulnerable to the danger of a latent infection becoming active.