Skin tuberculosis is just one of the ways that this bacterial infection can affect your body. While less contagious than some types of tuberculosis, it can still be spread from person to person.

Skin tuberculosis is an infection that happens when the bacteria that cause tuberculosis, Mycobacterium tuberculous, affects your skin. The infection, also called cutaneous tuberculosis, is very rare.

It can happen as a result of tuberculosis spreading to your skin or because there’s direct contact with tuberculosis bacteria through an open cut or wound.

Skin tuberculosis causes symptoms such as skin discoloration, lesions, raised nodules, and painful ulcers. But treating the infection with antibiotics can resolve these symptoms. Keep reading to learn more about the causes, symptoms, and treatment options for skin tuberculosis.

Skin tuberculosis is caused by exposure to the tuberculosis bacteria. Normally, this happens when you inhale droplets that are infected with tuberculosis bacteria as another person exhales them.

When someone has tuberculosis, the bacteria can travel from their lungs to other parts of their body, including their skin, through their bloodstream or lymphatic system. It’s also possible to develop skin tuberculosis by coming in contact with the bacteria through an opening in your skin such as a needlestick, cut, or open wound.

Some people have a higher risk of skin tuberculosis. They include:

Is skin TB contagious?

Tuberculosis most often spreads through droplets. This means it spreads when someone with tuberculosis coughs, sneezes, sings, or talks and other people breathe in the infected droplets. It’s common for repository conditions, such as the flu or coronavirus disease 2019 (COVID-19), to spread this way.

You can read more about this kind of infection spread here.

Skin tuberculosis is different. You can’t spread skin tuberculosis simply by being in the same room as another person or even by touching them. But skin tuberculous can be caused by direct contact with tuberculous bacteria on an open cut or wound. So, it’s possible to spread skin tuberculous to someone else.

The symptoms of skin tuberculosis depend on the severity of your infection, your underlying health, and the area of your body that’s affected.

For instance, when skin tuberculosis spreads from a tuberculosis infection in your lungs, it causes small bumps that form large groups, creating the appearance of shiny, tough, brown, or discolored patches on your skin. This is called lupus vulgaris.

Symptoms of other types of skin tuberculosis include:

  • Tuberculosis chancre: Tuberculosis chancre features small bumps on your face, arms, and legs that later merge together to become lesions of discolored skin. It can spread to your lymph nodes, resulting in inflammation.
  • Erythema induratum of Bazin (EIB): EIB features dark lesions that appear on your legs and that leave scars after they fade. It primarily affects middle-aged and younger females. Without treatment, EIB can reoccur.
  • Tuberculous verrucosa: Tuberculous verrucosa features skin buildup called plaque and thick, shiny lesions on your hands, fingers, and toes.
  • Scrofuloderma: Scrofuloderma features painless nodules that grow larger until they burst. This forms ulcers and discolored growths that can discharge pus. It’s most common in people with human immune deficiency syndrome (HIV) and in very young children.
  • Papulonecrotic tuberculids: Papulonecrotic tuberculids features large lesions that form on your face, ears, abdomen, and buttocks. It also causes symptoms such as energy loss and fever.
  • Idiopathic granulomatous mastitis (IGM): IGM features painful lesions on your breast that scar. This type of skin tuberculosis is most commonly experienced by people who are nursing.
  • Tuberculous orificialis: Tuberculous orificialis features large painful ulcers that form in your mouth, throat, genitals, and around and in your anus. Sometimes, your fallopian tubes and membrane of your uterus can also be affected. This severe form of skin tuberculosis primarily affects seniors.

TB infections are treated with a combination of antibiotics. The exact treatment plan can depend on your exact infection and symptoms. But typically, you’ll take a combination of four antibiotics for around 6 months. Your dose will be heaviest during the first 2 months.

Sometimes, you might need additional treatment for skin tuberculosis. This can include surgery to remove any very large or painful growths and might be followed by surgery to repair your skin’s appearance. Topical treatments to relieve itching, pain, or other symptoms might also be used.

Is skin TB dangerous?

Most forms of skin tuberculosis are very treatable, and some can even resolve on their own. But some infections are more severe.

Treatment can be more challenging for people who have conditions that affect their immune systems or for people who are affected by antibiotic-resistant forms of the bacteria. A healthcare professional can help you understand the factors that affect your outlook.

Skin tuberculosis is a rare form of tuberculosis that happens when bacteria that cause tuberculosis infect your skin.

Skin tuberculosis symptoms can vary depending on the specific infection, a person’s underlying health, their age, and the skin that’s affected, but common symptoms include lesions, ulcer nodules, and discolored skin.

Treatment for skin tuberculosis is typically a 6-month course of antibiotics. Additional treatments to address skin symptoms might also be options.