Turberculosis

Tuberculosis (TB) is a dangerous -- often deadly -- disease. Testing, preventative measures, and aggressive treatment are important. TB is the most common opportunistic infection.

Classification

Description

• Infection: TB is transmitted when a person with active TB coughs or sneezes, releasing microscopic particles into the air. These particles, also called droplet nuclei, contain live tubercle bacteria, and may result in infection when inhaled by another person. Once infected by TB, most people, remain healthy and develop only latent infection. People with latent infection are neither sick nor infectious. However, they do have the potential to become sick and infectious with active TB. (GMHC)
• An earli OI: Active TB often occurs early in the course of HIV infection, often months or years before other OIs. In fact, TB may be the first indication that a person is HIV-infected. TB also causes disease outside the lungs of HIV-infected people, particularly in the later stages of AIDS. (NIH)
• Multi-drug Resistant TB: Of particular concern for people with AIDS is multi-drug- resistant TB (MDR-TB). MDR-TB occurs when patients fail to take their TB medicine for the prolonged periods necessary to destroy all parts of the TB organism and it becomes resistant to the drugs. These resistant organisms can be spread to other people. Even with treatment, for individuals coinfected with HIV and MDR-TB, the death rate may be as high as 80 percent, as opposed to 40 to 60 percent for people with MDR-TB alone. The time from diagnosis to death for some patients with HIV and MDR-TB may be only months as they are sometimes left with no treatment options. (NIH)
• In about half of the HIV+ people with TB, the infection involves more than just the lungs. Other targets include the lymphatic system.
• Symptoms include: cough, fever, night sweats, weight loss, fatigue.
• Diagnosis is usually made with a skin test.
• The US Centers For Disease Control considers TB an AIDS-defining condition.

Danger Zone

• TB is more frequent for those with CD4+ cells less than 200/mm but can occur at any CD4+ count.

Prevention

• The US CDC recommends treatment for any HIV+ person with latent (inactive, no symptoms) M. tuberculosis. That diagnosis is made using skin tests.
• Prophylaxis (prevention) is usually isoniazid.
• Outside the US, BCG vaccination has been used for the prevention of TB.

1. If you test positive for TB, you are infected with TB.
2. If you test negative for TB but positive for mumps or candida, you do not have TB. This is the result you want! Those with functioning immune systems will test positive for mumps, candida, or both ... so a positive result on these tests means the negative TB test can be trusted.
3. If you test negative for all three, then you have anergy, which means your immune system is to damaged to respond to common antigens.

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   Treatment

   • Treatment usually includes multiple drugs: isoniazid, rifampin, pyrazinamide, ethambutol (or streptomycin).
   • Some mutations of TB are resistant to some of the common drugs. There are susceptibility tests that can show which drugs will work on a particular strain.
   • The US CDC recommends DOT (directly observed therapy) -- where a nurse watches each drug dose being taken. The biggest reason for TB treatment failure is a failure to take the medicines.
   • Some with late-stage AIDS have trouble absorbing the drugs. Doctors can sometimes run tests to see if malabsorption is a problem.

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   See Also...

   • ÆGIS Knowledgebase: Turberculosis
   • Being Alive newsletter: TB Screening
   • NIAID Alert: TB and HIV Replication
   • GMHC: What TB Is (1993)

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   This information is designed to support, not replace, the relationship that exists between you and your doctor.
   ©1998-2006. AEGiS.