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Miliary Tuberculosis (TB)

(Disseminated Tuberculosis)

By

Edward A. Nardell

, MD, Harvard Medical School

Medically Reviewed Sep 2022
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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 Tuberculosis (TB) Tuberculosis is a chronic contagious infection caused by the airborne bacteria Mycobacterium tuberculosis. It usually affects the lungs, but almost any organ can be involved. Tuberculosis... read more Tuberculosis (TB) 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

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

Mycobacterium tuberculosis can sometimes be identified by doing nucleic acid amplification tests (NAATs) on certain types of samples. NAATs look for an organism's unique genetic material, its DNA or RNA (which are nucleic acids). NAATs use a process that increases the amount of the bacteria's DNA or RNA so that it can be more easily identified.

A chest x-ray may show the thousands of small spots that are typical in miliary 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 (MRI).

Treatment of Miliary TB

  • Antibiotics

  • Sometimes corticosteroids

  • Sometimes surgery

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

Tuberculosis bacteria can easily develop resistance Drug resistance Tuberculosis is a chronic contagious infection caused by the airborne bacteria Mycobacterium tuberculosis. It usually affects the lungs, but almost any organ can be involved. Tuberculosis... read more Drug resistance to antibiotics, particularly when people do not take the drugs regularly or for as long as they are supposed to.

Corticosteroids may help if the pericardium or meninges are affected.

Surgery is needed for some complications of miliary tuberculosis.

NOTE: This is the Consumer Version. DOCTORS: VIEW PROFESSIONAL VERSION
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