Most people think of tuberculosis, often called TB, as a serious disease that affects the lungs. That's true, but it can also affect other parts of your body, including your brain and spine. It's not a problem for most people with healthy immune systems: You can have TB germs in your body and not get sick yourself or spread the disease to others.
But it's different for someone who is HIV-positive. When your immune system is weak, TB germs can multiply and cause symptoms. Someone infected with both HIV and TB is at least 10 times more likely to develop active TB, especially when their CD4 count is under 200. Regardless of your CD4 count, having both infections also means you have AIDS, the advanced stage of HIV.
Worldwide, TB is a leading cause of death for people with HIV.
Taking steps to prevent this opportunistic infection and getting tested and treated for it are an important part of living with HIV. It not only helps control tuberculosis, but it helps prevent greater damage to your immune system.
How You Can Get It
The bacteria that cause tuberculosis, Mycobacterium tuberculosis, travel through the air when you cough or sneeze. But you're not likely to get TB through a single contact. And you can't get it from sharing dishes or utensils, or by touching someone who has it.
Your chances of getting TB are much greater if you're around an infected person often, like someone you work with or live with. Tuberculosis spreads more easily in crowded places with little fresh air, too. Talk to your doctor about whether it's safe for you to spend a lot of time somewhere like a hospital, clinic, doctor's office, nursing home, jail or prison, or a shelter for homeless people.
You're also more likely to get TB if you:
- Are pregnant
- Are younger than 5 years old or older than 65
- Drink alcohol or inject drugs
- Don't eat well
Active tuberculosis makes you feel sick with these symptoms:
- A bad cough that lasts for more than 2 weeks
- Coughing up mucus or blood
- Chest pain
You may also have:
- Weakness or fatigue
- Weight loss
- Not much of an appetite
- Fever or chills
- Night sweats
Getting a Diagnosis
As soon as you know you have HIV, you should get a tuberculin skin test (TST). You'll get a small amount of liquid with a TB protein injected under the skin on your arm. After 2 or 3 days, a health care provider checks the injection site; swelling and redness are signs of tuberculosis infection. Or you could get a blood test called interferon-gamma release assay (IGRA).
A positive TST or IGRA doesn’t necessarily mean that you have TB disease (sometimes referred to as “active” TB). This is because the TB germ can remain silent in your body (sometimes called “latent” TB).
Other tests can help confirm whether you have active TB disease. These are important to get if you have symptoms that suggest TB (even if your TST or IGRA was negative) or if an earlier TST or IGRA was negative but is now positive:
- A chest X-ray, which takes a picture of your lungs
- A TB smear test, where your doctor takes a sample of the phlegm you've coughed up and looks at it under a microscope for signs of bacteria
- A sputum culture, which lets the bacteria in the mucus grow so a technician can check for the one that causes TB
- A molecular test, which can determine if you have TB DNA in your sputum
After a negative TST, you should get tested again periodically, if you live or work in a setting where you might get exposed to someone with TB.
Babies born to HIV-positive moms should get tested at 9-12 months of age.
Whether or not your TB is active, you will need to be treated right away.
There are drugs that prevent tuberculosis infection from becoming the disease. Your doctor will need to confirm that you don't have active TB first. Then you'll take isoniazid, or INH (Nydrazid), for 9 months with pyridoxine, a form of vitamin B6, to prevent the side effect of nerve damage in your hands and feet. Or, you may be able to take rifampin, or RIF (Rifadin)for 4 months, or a combination of INH and rifapentine (RPT) weekly for 3 months.
To treat active tuberculosis, you'll take a combination of drugs for several months that commonly include:
- Ethambutol, or EMB (Myambutol)
- Isoniazid, or INH (Nydrazid)
- Pyrazinamide, or PZA (Tebrazid)
- Rifampin, or RIF (Rifadin)
Drugs for HIV and for TB don't always work well together. Your doctor will decide which combination of medications will be best for you. If you have active TB, your TB must be treated immediately. If you are already on ART, your doctor may have to adjust your HIV drugs. If you are not already on ART, your doctor will decide how soon you should start ART.
If you have active TB, at you'll likely need to stay away from others so you don't spread TB. Then, after about 3 weeks of treatment, you won't be able to infect anyone. Your doctor can confirm this with three negative TB smear tests.
Keep taking your TB medications the way your doctor told you to, and finish them. If you stop or don't take them as often as your doctor says you should, the germs can become resistant, you could get sick again, and the drugs may stop working.