HIV/TB Coinfection

What's the Problem?

Tuberculosis (TB) is a bacterial disease that is spread from person to person. It is common for people to become infected with TB and show no symptoms. A healthy immune system can contain and handle the TB bacillus; one-third of the world's population is infected, but not actively sick (2). People with this type of latent TB infection do not feel sick, do not have any symptoms, and cannot spread TB, but they may develop TB disease at some time in the future if they do not get proper treatment.

Active TB illness develops in those with immune systems that are not strong enough to manage the bacterial infection, making them actively sick. This includes persons whose immune systems are weakened by malnutrition or old age, overwork, and many other causes including HIV infection.

In combination, HIV and TB are a deadly pair. When TB is suspected in people who are also HIV-positive, it is important to evaluate them for active TB disease immediately and if needed, begin TB treatment. Globally, an estimated one-third of those living with HIV infection are co-infected with TB. TB is a leading killer among HIV-infected people; about 200,000 people living with HIV/AIDS die from TB every year, most of them in Africa (2).

Symptoms of TB disease differ, depending on where in the body the TB bacteria settle. TB can affect the bones, joints, lymph nodes, kidneys, liver, and brain, but the most common form is pulmonary TB, which affects the lungs. An active case of pulmonary TB may cause a bad cough that lasts longer than two weeks; chest pain, and/or coughing up mucus or blood. Other general symptoms of TB are weakness or fatigue, weight loss, lack of appetite, chills, fever; and/or night sweats. Without treatment, nearly half of all such patients die slowly and painfully, within five years. Many others live with chronic illness.

Who's at Risk?

Anyone exposed to someone with active pulmonary TB could be at risk for TB infection, but only 10 percent of healthy people infected with the TB bacilli will actually get sick (3). The numbers are very different for those infected with HIV: HIV-positive people who become infected with TB are 100 times more likely to develop active TB disease than those without HIV infection.

With increased international travel and a global marketplace, no region of the world is immune from outside influences. A growing number of TB cases in the United States are among people born in areas where TB is common, such as Asia, Africa, and Latin America. In 2008, the rate of TB was ten times higher among foreign-born persons in the United States, than among the US-born (4).

Anyone with a depressed immune system who is exposed to TB, or has been carrying the TB bacillus, is more likely than a healthy individual to develop active TB disease.

Can It Be Prevented?

Everyone infected with HIV that is suspected to have TB, should be evaluated for TB disease, and if needed, started on anti-TB treatment. The most effective strategy for ensuring the completion of treatment against TB is directly observed therapy (DOT), which means that the patient will take a course of antibiotics with the assistance of an observer who makes sure the patient completes the course of medication. This approach is important because not only will partial treatment result in an uncured patient, incomplete or partial treatment of TB can lead to multi-drug resistant strains of the disease. Multidrug-resistant TB (MDR TB) is TB that is resistant to at least two of the best anti-TB drugs—isoniazid and rifampin. MDR TB is extremely difficult to treat and can be fatal—and like regular TB, it is contagious. Cases of spreading MDR TB have been confirmed in all regions of the world (5). HIV-positive persons who do not have active TB disease, but have high exposure to persons with active TB disease, may be considered for TB preventive therapy which can be effective to prevent progression to active TB disease.

In addition, all patients who are diagnosed with active TB disease, who do not know their HIV status, should be offered HIV testing. All TB patients who test HIV-positive should be linked to HIV prevention, care and treatment services, including antiretroviral therapy (ART).

Unfortunately, co-infection with HIV and TB presents another challenge. There are possible complications from interactions between the drugs used to treat HIV and the drugs used to treat TB. It is important for HIV-infected patients to be closely monitored by a physician during any type of treatment to make sure they are not hurt by side effects from taking TB and HIV medicines together. Monitoring is also important to ensure the TB medicines are not interacting with patients' HIV medicines in a way that could alter their effect (6).

The Bottom Line

Anyone can get TB as it can be transmitted through air by anyone with active TB. A person with HIV has a very high risk of developing active TB disease. Fortunately, a person living with both TB and HIV may lead a relatively normal life if diligently following a tailored drug regimen that addresses both diseases. Active TB disease can be prevented and treated, even in people with HIV infection. If they have latent TB infection, they may consider TB preventive therapy to prevent them from developing active TB disease. If they have active TB disease, they must take medicine to treat the disease and prevent spreading TB to others.

Case Example

Connie, age 19, is from Botswana. When she was 14, she went to live with her aunt in South Africa. There, she was raped several times by a friend of her aunt's. Each time she tried to leave, he beat and abused her. She was finally able to escape and return home to her family in Botswana. Two months ago, she was diagnosed with TB. Knowing of the link between HIV and TB, Connie's father took her to be tested. She tested positive for HIV. She believes she contracted HIV from her aunt's friend, as two other women he had raped had died from AIDS-related diseases. Although her family has been mostly supportive, Connie has suffered greatly with the stigma of both TB and HIV. Because she has TB, people automatically accuse her of being HIV-positive, without even knowing her status. In her family, only her younger brother treats her badly, accusing her of infecting the household. He also accuses her of bringing shame on the family. She has separate eating utensils, bed linen, and bath towels. Connie is unemployed and does odd jobs when she can find them. She goes to the hospice three times a week for some calm and to escape from her home situation. All she hopes for at the moment is just to get better and back to full strength, then she will think about her future. She has been taking her TB treatment for about two months and feels much better (7).