Tuberculous peritonitis occurs when tuberculosis (TB) spreads to the protective lining of your abdomen. This can cause abdominal pain and swelling, but early antibiotic treatment can help.

Tuberculous peritonitis, or peritoneal TB, is a serious infection of the peritoneum inside your abdomen. TB causes the infection. The term “peritonitis” itself refers to inflammation of the peritoneum, often due to infection.

TB is a serious bacterial infection primarily known for developing in the lungs. However, TB can also affect other areas in your body, such as your brain or gastrointestinal (GI) system. It can also cause tuberculous peritonitis.

Learn more about this type of TB, including its causes, possible symptoms, and overall outlook.

TB symptoms depend on which part of the body the condition affects. For example, pulmonary TB infections may cause severe cough and chest pain.

Symptoms of peritoneal TB may include a combination of peritonitis and general TB symptoms.

Symptoms of peritonitis may include:

  • severe abdominal pain
  • abdominal swelling
  • stomach tenderness
  • rapid heart rate
  • inability to urinate, or going less often than regular
  • loss of appetite
  • diarrhea

These symptoms may be subtle at first, but they tend to be gradually progressive.

Other symptoms seen in all types of TB include:

  • fatigue
  • weakness
  • fever
  • chills
  • night sweats
  • unintentional weight loss

The peritoneum is the lining in your abdomen that covers and protects important GI organs. These include your liver, kidneys, and stomach. As such, tuberculous peritonitis is a GI form of abdominal TB.

While TB is often pulmonary (in your lungs), it can attack other organs in your body. In some cases, TB infections may begin in your lungs and then spread to other organs.

The bacterium Mycobacterium tuberculosis causes all TB infections. Like other bacterial infections, transmission occurs when you breathe in air droplets that contain the bacteria.

Anyone with a TB infection or in close contact with someone with this type of infection may be at risk of tuberculous peritonitis. General risk factors for TB include:

  • being under 5 years old
  • being an older adult
  • a history of TB infection that was not completely treated
  • a history of substance or alcohol use disorder
  • having preexisting conditions, such as HIV, diabetes, or cancer, that make it more difficult for the immune system to fight infections
  • taking immunosuppressive medications that weaken your immune system
  • living in an area where TB infections are prevalent

More specific risk factors for TB-related GI forms may involve preexisting conditions that involve the GI system. These include liver cirrhosis, end stage renal disease, or HIV.

There are three types of tuberculous peritonitis:

  • Wet: This most common subtype causes ascites, the buildup of free fluid in your abdomen.
  • Fibrotic: This subtype is characterized by abdominal masses and thickening of the omentum, a layer of fat in the peritoneum.
  • Dry: This least common subtype is characterized by scar tissue on your bowels and irregular lymph nodes.

You may also have a combination of the types.

Experts consider peritoneal TB among the most challenging types of TB outside of the lungs (extrapulmonary) to diagnose.

A doctor may confirm suspected symptoms of peritoneal TB with abdominal imaging tests. These can include computed tomography (CT) scans and ultrasound imaging. Such imaging tests can also rule out other possible causes of peritonitis, such as ulcers or pancreatitis.

An imaging test may reveal inflammation or damage to the peritoneum. A doctor may also see fluid buildup in your abdomen that may be causing severe bloating or distension, as well as any signs of masses.

Doctors also often collect a sample of ascitic fluid for lab analysis. Healthcare professionals use ascitic fluid analysis to check for TB bacteria, immune cells that suggest an infection, or elevated levels of enzymes like lactate dehydrogenase.

Additionally, a doctor may order blood, urine, and skin tests to confirm this infection while also obtaining other important information about your overall health, which collectively may influence treatment recommendations.

Doctors prescribe antibiotics to treat peritoneal TB as they typically do with other active forms of TB. However, you may need intravenous antibiotics administered in a hospital.

TB medications may cause liver toxicity in some people. This can lead to serious side effects in people with liver disease and may require changing the treatment approach.

If having tuberculous peritonitis leads to you experiencing organ damage, you may need surgery. If peritoneal TB severely damages your organ, surgically removing the peritoneum may also be necessary.

Possible complications of peritoneal TB include:

Tuberculous peritonitis can damage the peritoneum, which protects internal organs within your GI tract. Left untreated, TB may also affect these organs. These include, but are not limited to, your liver, kidneys, and bowels.

Severe tuberculous peritonitis that progresses to organ damage can lead to death. This makes early diagnosis and treatment important.

People with peritoneal TB have a higher likelihood of dying. This may be because the condition is so challenging to diagnose promptly. Older research indicates the death rate is 15–31%.

When healthcare professionals detect and treat TB early, people living with the condition have a more positive outlook. Experts estimate the death rate for people living with untreated TB is more than 50%.

The likelihood of dying from peritonitis is higher in older adults.

If you or a loved one have recently received a diagnosis of tuberculous peritonitis, consider discussing the following information with a doctor:

Is tuberculous peritonitis curable?

Peritoneal TB is curable with antibiotics. Left untreated, the infection may lead to life threatening complications, such as internal organ damage.

How long is treatment for peritoneal TB?

All types of TB require long-term treatment. Peritoneal forms are no exception. Depending on the severity and your body’s response to anti-tuberculous therapies, you may need treatment for 6–12 months for peritoneal TB.

How rare is peritoneal TB?

Overall, tuberculous peritonitis is rare in the United States.

However, experts estimate that peritoneal TB makes up about 5% of all extrapulmonary TB cases, according to previously reported data. Tuberculous peritonitis is also the sixth most common form of extrapulmonary TB.

Can I have both pulmonary and peritoneal TB?

It’s possible to have both pulmonary and peritoneal TB. In such cases, the infection may spread from your lungs to your peritoneum and other parts of your body. This is also called disseminated TB or miliary TB (a common subtype of disseminated TB).

While not as common as pulmonary TB, peritoneal TB is serious and possibly life threatening when left untreated.

Consider seeing a doctor right away if you experience any possible signs of this condition, such as severe abdominal pain and swelling.

You may also consider talking with a doctor if you have certain risk factors for tuberculous peritonitis, such as a history of TB.