Merck Manual

Please confirm that you are not located inside the Russian Federation

honeypot link

Miliary Tuberculosis (TB)

(Disseminated Tuberculosis)


Dylan Tierney

, MD, MPH , Harvard Medical School;

Edward A. Nardell

, MD, Harvard Medical School

Last full review/revision May 2018| Content last modified Jun 2018
Click here for the Professional Version

Miliary tuberculosis is a potentially life-threatening type of tuberculosis that occurs when a large number of the bacteria travel through the bloodstream and spread throughout the body.

Tuberculosis is a contagious infection caused by the airborne bacteria Mycobacterium tuberculosis. Tuberculosis usually affects the lungs in one or a few locations. Miliary tuberculosis is so named because the innumerable tiny spots that form in the lungs are the size of millet, the small round seeds in bird food.

Miliary tuberculosis may affect one organ or several organs or occur throughout the body. It most often affects the lungs, liver, and bone marrow but may affect any organ, including the tissues that cover the brain and spinal cord (meninges) and the two-layered membrane around the heart (pericardium).

Miliary tuberculosis occurs most often in the following:

  • Children under 4 years old

  • People with a weakened immune system

  • Older people

Symptoms of Miliary TB

Symptoms of miliary tuberculosis can be vague and difficult to identify. They include weight loss, fever, chills, weakness, general discomfort, and difficulty breathing.

Infection of the bone marrow may cause severe anemia and other blood abnormalities, suggesting leukemia.

If bacteria are intermittently released into the bloodstream from an unrecognized infection, people may have a fever that comes and goes and may gradually lose weight, wasting away.

Diagnosis of Miliary TB

  • Examination and culture of a sample from the infected area

  • Blood tests to detect tuberculosis

  • A chest x-ray

Diagnosis of miliary tuberculosis is similar to the diagnosis of pulmonary tuberculosis.

Samples of infected fluids may be examined under a microscope and/or sent to a laboratory to be grown (cultured) and tested. Samples may be

  • Blood

  • Cerebrospinal fluid, obtained by spinal tap (lumbar puncture)

  • Urine

  • Fluid from the space between the two layers of the membrane that surrounds the lungs (pleura)

  • Fluid from the space between the two layers of the membrane that surrounds the heart (pericardium)

  • Joint fluid

  • Bone marrow

The tuberculin skin test and blood tests to detect tuberculosis (interferon-gamma release assay) are done.

A chest x-ray may show the innumerable small spots that are typical in military tuberculosis. Other imaging tests are done, depending on which areas of the body are affected. They may include computed tomography (CT), ultrasonography, and magnetic resonance imaging.

Treatment of Miliary TB

  • Antibiotics

  • Corticosteroids

  • Sometimes surgery

Generally, treatment of miliary tuberculosis is similar to the treatment of pulmonary tuberculosis.

Antibiotics are given usually given for 6 to 9 months, unless the meninges are affected. Then antibiotics are given for 9 to 12 months.

Corticosteroids may help if the pericardium or meninges are affected.

Tuberculosis bacteria can easily develop resistance to antibiotics, particularly when people do not take the drugs regularly or for as long as they are supposed to.

Surgery is needed for some complications of military tuberculosis.

NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version
Click here for the Professional Version
Others also read

Also of Interest

Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID