Gastrointestinal tuberculosis is an uncommon form of tuberculosis infection that usually occurs when Mycobacterium tuberculosis affects your gastrointestinal (GI) tract.

Tuberculosis is a bacterial infection usually caused by Mycobacterium tuberculosis. This infection typically causes symptoms affecting the lungs and spreads through respiratory fluid when a person who has it:

  • coughs
  • speaks
  • sings
  • sneezes

Gastrointestinal tuberculosis can spread to your GI tract by swallowing contaminated phlegm from a TB lung infection or from your lungs through your bloodstream and lymph system.

It can affect any part of your gastrointestinal tract and can cause many different symptoms like abdominal pain or swelling. It has garnered the moniker “the great mimicker” since its symptoms can replicate those of many other GI diseases.

Read on to learn more about this rare form of tuberculosis.

Gastrointestinal tuberculosis is caused by Mycobacterium tuberculosis infection, usually after coming in contact with the respiratory fluids of a person who has it. This bacterium can travel from your lungs to your GI tract through your blood and lymph systems or via your swallowing infected phlegm.

Less commonly, gastrointestinal tuberculosis can develop from the ingestion of milk products infected with Mycobacterium bovis, a similar bacterium that can affect cows.

Gastrointestinal tuberculosis can affect various parts of your GI tract, including your:

  • esophagus, in rare cases
  • stomach
  • small intestines
  • large intestines
  • rectum and anus

Extrapulmonary tuberculosis

Tuberculosis that occurs outside your lungs is called extrapulmonary tuberculosis. It makes up about 15–20% of cases of tuberculosis infection. The most common places extrapulmonary tuberculosis develops are:

Gastrointestinal tuberculosis can cause symptoms that mimic those of many other GI conditions like Crohn’s disease or cancer.

The most common part of the GI tract affected is the end of your small intestines. In a 2023 autopsy study, 96% of more than 4,500 people with gastrointestinal tuberculosis had involvement in this area, with 10% also having involvement in the first part of the large intestines called the cecum.

The most common signs and symptoms include:

Roughly 6–38% of people with gastrointestinal tuberculosis also develop lung symptoms, which can include:

Risk factors for tuberculosis include:

  • being in close contact with people who have gastrointestinal TB
  • immigrating from parts of the world with high rates of tuberculosis
  • working or spending time in:
    • hospitals
    • homeless shelters
    • prisons
    • nursing homes
    • residential homes for people with HIV
  • smoking
  • heavy alcohol consumption
  • illicit drug use
  • conditions that weaken your immune system, such as:
    • receiving an organ transplant

Potential complications of gastrointestinal tuberculosis include:

The gold standard test for gastrointestinal tuberculosis is a bacterial culture created using a tissue sample from your intestinal mucosa collected with a long, thin tube called an endoscope.

Other tests for gastrointestinal tuberculosis include:

Tuberculosis is often curable with antibiotics. Usually, you’ll have to take antibiotics for at least 6 months, according to the U.K.’s National Health Service (NHS).

Antibiotics are the main treatment for gastrointestinal tuberculosis. The primary combination is a four-drug mixture consisting of:

  • isoniazid
  • rifampicin
  • pyrazinamide
  • ethambutol

Most guidelines recommend continuing treatment for 6 months.

Additional treatment may be required to treat complications of gastrointestinal tuberculosis. They may include:

  • endoscopic balloon dilation for strictures in the small intestines, which occurs in about a quarter of people
  • surgery to treat complications including:
    • bowel obstruction
    • bowel perforation
    • fistulas

The risk of death when gastrointestinal tuberculosis is left untreated has been reported at 6–20%.

Ways you can prevent gastrointestinal tuberculosis include:

  • treating latent tuberculosis infection if you have gastrointestinal TB but do not have symptoms
  • asking your doctor about preventive treatment if you have HIV
  • avoiding prolonged contact with people with tuberculosis, especially in crowded and enclosed environments like prisons or hospitals
  • eating nutritious foods like fruits and vegetables and staying physically active to support your immune system
  • taking extra care to avoid respiratory illnesses, which includes frequently washing your hands and wearing a mask when traveling to countries with high rates of tuberculosis

There is a tuberculosis vaccine, but the Centers for Disease Control and Prevention (CDC) reports that it’s not frequently administered in the United States.

It’s important to contact a doctor if you’ve been in an environment that increases your risk of developing tuberculosis and you develop potential lung or GI symptoms like:

  • abdominal pain
  • diarrhea
  • abdominal swelling
  • a persistent cough
  • fever

Gastrointestinal tuberculosis is caused by the bacterium Mycobacterium tuberculosis or Mycobacterium bovis. It can cause symptoms that mimic those of many other gastrointestinal conditions.

Gastrointestinal tuberculosis is not common in the United States and is often curable with antibiotics. Additional treatment like surgery may be needed to treat complications like bowel obstruction.