Treatment for Tuberculosis: Antibiotic Medications

肺结核是非常treatable in the United States but can require several months of antibiotics and monitoring by your doctor.

Tuberculosis (TB) has affected humans for millennia — even the ancient Greeks searched for a cure. But no effective treatment for TB existed until the mid-1800s, when the sanatorium, or “open air” cure, was first put into use. This led to the creation of facilities dedicated to housing and caring for people with TB. The sanatorium cure involved rest, fresh air, and a nutritious diet to strengthen the body's natural defenses against the bacteria that cause TB. (1,2) Being in the sanatorium also included isolation, to prevent others from becoming infected.

The firstantibioticagainst tuberculosis, streptomycin, was developed in the 1940s. Soon after, in the 1950s, the drugisoniazidwas developed along with the group of drugs called rifamycins. Antibiotic use replaced the need for sanatoriums, and the number of people with the disease in the United States and other developed countries began to go down drastically. (1,2)

The number of cases in the United States began to rise again in the mid-1980s, largely as a consequence of the HIV epidemic and decreased funding for public health programs in general, and TB clinics in particular. Now, latent TB (when the bacteria are present but dormant in your body and not making you sick or infectious) and active TB can be effectively treated inpeople with HIV. (3)

Tuberculosis is still common in certain countries, with the highest rates of new cases in India, Indonesia, China, the Philippines, Pakistan, Bangladesh, Nigeria, and South Africa. The World Health Organization (WHO) considers TB to be one of the top causes of death worldwide. This is largely due to lack of public health resources and access to quality care. (4)

Antibiotic Drugs Used for Tuberculosis Treatment

Today, there are several drugs approved for use against tuberculosis. The course of treatment depends on whether a person has latent or active TB.People with latent TB are generally treated with preventive care, so the disease doesn’t become active in the future and spread to others. Latent TB can be treated with one drug, and active TB usually requires a combination of four drugs.

Latent TB treatment can be overseen by your regular doctor, while people with active TB will be referred to an infectious disease specialist for treatment.

A number of drugs can be used to treat tuberculosis, and they’re often combined for better results: (5)

• Isoniazid
• Rifampin (Rifadin)
• Pyrazinamide
• Ethambutol (Myambutol)

A standard treatment regime for latent TB is taking isoniazid for six to nine months. (5)

Because so many strains of tuberculosis have developed resistance to certain antibiotics, treatment foractive tuberculosisinvolves the administration of several different antibiotics that have activity against TB. Lab tests known as drug susceptibility tests can determine which antibiotics will be more likely to cure a given case of TB. (4,5)

Drug treatment typically lasts at least six months and sometimes longer. Stopping treatment too early can result in the infection coming back and can lead to the development of drug-resistant tuberculosis.

The drugs used and the length of treatment are the same for both adults and children, according toAlexea Gaffney-Adams, MD,an internist andpediatricianwith a subspecialty in infectious disease at Stony Brook Medicine in Smithtown, New York.She notes that the dosage is based on a person’s weight.

People with tuberculosiswho take their medicine usually don’t relapse, saysLee Reichman, MD, MPH, a professor of medicine and epidemiology and the executive director emeritus at Rutgers Global Tuberculosis Institute in Newark, New Jersey.

Isolation for People With Active Pulmonary TB

Tuberculosis is considered a public health concern. For that reason, isolation is still a part of modern TB treatment. A person with activepulmonary tuberculosis(而不是latent TB) should be isolated until they respond to treatment. Active disease can still spread to others until the person has taken several doses of medication.

This could mean staying home or being quarantined in a medical facility. It usually takes no more than two weeks for medications to stop someone from being contagious. But for people with drug-resistant TB, guidelines on isolation remain unclear. (6)

The Emergence of Drug-Resistant Tuberculosis Superbugs

The treatment of tuberculosis and control of the disease's spread has been complicated worldwide by the emergence of multidrug-resistant tuberculosis (MDR-TB). It's defined as strains of TB that do not respond to at least isoniazid andrifampin, the two drugs that are the cornerstone of TB treatment.

The WHO considers MDR-TB to be a global public health crisis. In 2017, around 558,000 new cases of TB were estimated to be resistant to rifampin (the most effective first-line drug), and over 80 percent of those cases were MDR-TB. Almost half of all MDR-TB cases are found in India, China, and Russia. (4)

Some people develop an even stronger, more serious form of MDR-TB known as extensively drug-resistant TB (XDR-TB). People with XDR-TB may be left without treatment options if the bacteria has become resistant to the most effective second-line drugs. (4)

Drug-resistant TB is much less common in the United States. The Centers for Disease Control and Prevention (CDC) reported 123 MDR-TB cases for 2017. (7)

Infection-causing bacteria will naturally adapt to become resistant to certain antibiotics, evolving into superbugs that are unaffected by most antibiotics. But the way that humans have used antibiotics over the years hassped up this process.

Some causes of drug-resistant TB include these tactics:

• Overuse of antibiotics, such as taking them to treat viral infections, for which they are ineffective, is one of the reasons that certain bacteria have become resistant to common antibiotics.
• When a healthcare provider prescribes an incorrect drug or dose, the bacteria can become resistant.
• In some areas of the world, there is no access to the proper drugs needed to treat people with TB.

Another major issue is when people fail to take a full course of antibiotics when a bacterial infection is present. When antibiotics are stopped early, the bacteria that have not yet been killed often develop resistance to the drug being used for treatment. This is a common problem with TB treatment, during which antibiotics need to be taken daily for several months. (8)

Treatment of drug-resistant TB can last 20 to 30 months and involve a combination of antibiotics, both injectable and oral. (9)

Commonly used injectable drugs include the following:

• Amikacin (Amikin)
• Capreomycin
• Streptomycin

Bedaquiline (Sirturo)is a newer drug that may be added to an existing antibiotic combination.

Directly Observed Therapy to Help With TB Treatment

One of the approaches that public health officials have taken to combat multidrug-resistant tuberculosis is directly observed therapy (DOT). In DOT, a trained healthcare worker provides each dose of medication, watches the person swallow it, and documents that the medication has been taken. The professional may meet a person at home or at a TB clinic. (10)

“You become noninfectious within a week or two of taking your medicine,” says Dr. Reichman. When people don’t feel sick anymore, it can be tempting to stop taking medication before it finishes the job of killing all the TB bacteria. “Symptoms go away very quickly, so people think they don’t need to take the rest of the medicine,” he says.

Studies show a higher cure rate among people under DOT than among those self-administering their tuberculosis drugs. In the United States from 1993 to 2013, DOT for people with MDR-TB had a 77 percent lower rate of death when compared with people responsible for taking their own drugs This success rate may also have to do with people getting access to other resources while under supervision. (11)

While anyone with tuberculosis is a candidate for DOT, the CDC specifically recommends that people in the following groups receive it:

• People with drug-resistant TB
• People receiving intermittent therapy
• Homeless or unstably housed people
• People who abuse alcohol or illegal drugs
• People who are unable to take pills on their own due to mental, emotional, or physical disabilities
• Children and adolescents
• Anyone with a history of not following a prescribed drug regimen

Reichman notes that technology has allowed for DOT to be done via video, which is now an option for some people.

The Possible Side Effects of TB Medications

Medications that treat TB can be toxic to the liver. Even people who aren’t under DOT will need to have regular visits with their doctor during treatment to monitor how well their body is tolerating the medications. (12)

Side effects aren’t very common but can be dangerous when they do happen. (9,12)

Contact your doctor right away if you experience any of the following:

• Yellow skin or eyes
• Nausea or vomiting
• Loss of appetite
• An unexplained fever that doesn’t go away
• Dark-colored urine