Tuberculosis, an infection caused by the bacterium Mycobacterium tuberculosis, is a significant global health issue that primarily affects the lungs but can damage other parts of the body. While the disease can be serious, it is curable with specific antibiotic treatments designed to eliminate the bacteria. Successful outcomes depend on receiving a proper diagnosis and adhering to the prescribed course of therapy.
Treatment for Latent TB Infection
Latent tuberculosis infection (LTBI) occurs when an individual has the Mycobacterium tuberculosis bacteria in their body, but it remains inactive. People with LTBI do not feel sick, have no symptoms, and cannot spread the bacteria to others. Treatment is a proactive measure to prevent the latent infection from progressing to active TB disease.
The medication plans for latent TB are shorter and involve fewer drugs than those for active disease. The U.S. Centers for Disease Control and Prevention (CDC) recommends regimens such as a three-month course of isoniazid and rifapentine or a four-month daily course of rifampin. These options are effective in eliminating the dormant bacteria and reducing the likelihood of future illness. The choice of regimen depends on a person’s age, other health conditions, and potential for drug interactions.
Standard Treatment for Active TB
Active TB disease manifests when the bacteria are actively multiplying, leading to symptoms like a persistent cough, fever, and weight loss. Unlike latent TB, active TB is contagious and requires a more intensive, multi-drug regimen to cure the infection and prevent its transmission. The standard for treating drug-susceptible active TB is a six-month course divided into two phases.
The initial two-month period is the intensive phase. During this time, patients take a combination of four antibiotics to quickly kill the multiplying bacteria, which leads to a rapid improvement in symptoms and renders the patient non-contagious. These medications are:
- Isoniazid
- Rifampin
- Pyrazinamide
- Ethambutol
Following the intensive phase, treatment moves into a four-month continuation phase. The regimen is simplified to two drugs, most commonly isoniazid and rifampin. The purpose of this extended period is to eliminate any persistent bacteria that survived the initial treatment. Completing the full six-month course is necessary to ensure the infection is completely cured and to prevent a relapse.
Managing Drug-Resistant TB
Drug-resistant TB emerges when the bacteria are no longer killed by at least one of the main antibiotic drugs. The most common form is multidrug-resistant TB (MDR-TB), which is defined by resistance to both isoniazid and rifampin, the two most effective first-line TB drugs. An even more severe form, extensively drug-resistant TB (XDR-TB), shows resistance to these drugs plus some of the most effective second-line medications.
Treating these resistant forms of tuberculosis is significantly more complicated and lengthy. It requires the use of second-line drugs, which can have more side effects. The treatment duration for drug-resistant TB can extend for many months or even years. A health provider will select a combination of drugs based on laboratory testing that shows which medications will be effective against the specific strain of bacteria.
The regimens for drug-resistant TB can be demanding for patients due to the long duration and potential for adverse effects. Medications may include fluoroquinolones or injectable antibiotics like amikacin. The complexity of these treatments underscores the importance of correctly treating standard TB from the outset to prevent resistance from developing.
The Importance of Treatment Completion and Monitoring
Strictly following the prescribed medication schedule is necessary to cure tuberculosis. Stopping treatment too soon or taking medicines incorrectly can lead to a relapse of the illness and is a primary driver for the development of drug-resistant strains of the bacteria. When the full course is not completed, some bacteria may survive and mutate.
To help individuals complete their treatment, many public health programs use a strategy called Directly Observed Therapy (DOT). Through DOT, a healthcare worker or another designated individual meets with the patient to watch them take their medication. This approach provides support and ensures that every dose is taken as prescribed.
Throughout the treatment for any form of TB, regular medical monitoring is necessary. The antibiotics used can cause side effects, such as nausea, skin rash, or more serious issues like liver inflammation or vision problems. Healthcare providers will schedule regular check-ups to ask about side effects and may perform tests to monitor for any adverse reactions, allowing for the safe management of the treatment process.