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Tuberculosis (TB) is an infectious disease that primarily affects the lungs. Tuberculosis bacteria spread from person to person via tiny droplets released into the air by coughs and sneezes.
Once uncommon in developed countries, tuberculosis infections began to rise in 1985, owing in part to the emergence of HIV, the virus that causes AIDS. HIV weakens a person's immune system, making it incapable of combating tuberculosis germs. Tuberculosis began to decline again in the United States in 1993, owing to stronger control programs. However, it remains a source of concern.
Many tuberculosis strains are resistant to the drugs most commonly used to treat the disease. People with active tuberculosis must take a variety of medications for months in order to clear the infection and avoid antibiotic resistance.
WHAT ARE THE STAGES OF TUBERCULOSIS?
The stages of tuberculosis are as follows:
- Exposure: This occurs when a person comes into contact with or is exposed to another person who has tuberculosis. A negative skin test, a normal chest X-ray, and no signs or symptoms of the disease will be observed in the exposed person.
- Latent TB infection: This occurs when a person has tuberculosis bacteria in their system but no symptoms of the disease. The immune system of a person infected with tuberculosis (TB) protects them from the organisms. In most people who are infected, the TB remains dormant throughout their lives. This individual would have a positive skin or blood test for tuberculosis but a normal chest X-ray or one that only shows scarring from the disease. Other parts of the body would show no signs of active infection.
- TB disease: This person is displaying signs and symptoms of an active tuberculosis infection. The individual may have a positive or negative skin or blood test for tuberculosis and a positive chest X-ray, biopsy, or other finding indicating active infection.
WHAT ARE THE SYMPTOMS OF TUBERCULOSIS?
Although your body can harbor the bacteria that cause tuberculosis, your immune system is usually capable of keeping you healthy. As a result, physicians distinguish between:
- Latent tuberculosis: You have tuberculosis, but the bacteria in your body are dormant and cause no symptoms. Latent tuberculosis, also known as inactive tuberculosis or tuberculosis infection, is not contagious. Because latent tuberculosis can progress to active tuberculosis, treatment is critical.
- Active tuberculosis: This condition, also known as tuberculosis, makes you sick and, in most cases, can spread to others. It can happen weeks or years after being infected with the TB bacteria.
Active tuberculosis symptoms include:
- Coughing for three weeks or more
- Coughing up blood or mucus
- Pain in the chest, or pain when breathing or coughing
- Weight loss that was unintentional
- Fatigue
- Fever
- Sweating at night
- Chills
- Appetite loss
Tuberculosis can also affect other organs, such as the kidneys, spine, or brain. When tuberculosis occurs outside of your lungs, the signs and symptoms vary depending on the organs involved. For example, tuberculosis of the spine may cause back pain, and tuberculosis of the kidneys may result in blood in the urine.
WHAT ARE THE CAUSES OF TUBERCULOSIS?
Tuberculosis is caused by bacteria that spreads from person to person via microscopic droplets in the air. When someone with untreated, active tuberculosis coughs, speaks, sneezes, spits, laughs, or sings, this can happen.
Although tuberculosis is contagious, it is difficult to contract. You are much more likely to contract tuberculosis from someone with whom you live or work than from a stranger. Most people with active tuberculosis who have received adequate drug treatment for at least two weeks are no longer contagious.
HIV and tuberculosis
Because of the spread of HIV, the virus that causes AIDS, tuberculosis cases have increased dramatically since the 1980s. HIV suppresses the immune system, making the body's ability to control tuberculosis bacteria difficult. As a result, people with HIV are much more likely than people who are not HIV positive to contract TB and progress from latent to active disease.
Drug-resistant tuberculosis
Because of the rise in drug-resistant strains, tuberculosis remains a major killer. Some tuberculosis germs have evolved the ability to survive despite medication over time. This is due in part to people failing to take their medications as prescribed or failing to complete the course of treatment.
When an antibiotic fails to kill all of the bacteria it targets, drug-resistant tuberculosis strains emerge. The bacteria that survive become resistant to that drug and, in many cases, other antibiotics as well. Some tuberculosis bacteria have developed resistance to commonly used treatments like isoniazid and rifampin (Rifadin, Rimactane).
Some TB strains have also developed resistance to drugs that are less commonly used in TB treatment, such as fluoroquinolone antibiotics and injectable medications such as amikacin and capreomycin (Capastat). These drugs are frequently used to treat infections that are resistant to more commonly used antibiotics.
WHAT ARE THE RISK FACTORS FOR TUBERCULOSIS?
Tuberculosis can affect anyone, but certain factors can increase your risk, such as:
Weakened immune system
A strong immune system can often defeat tuberculosis bacteria. Several conditions and medications, however, can weaken your immune system, including:
- HIV/AIDS
- Diabetes
- Severe kidney disease
- Certain types of cancer
- Cancer treatment, such as chemotherapy
- Anti-rejection drugs for transplanted organs
- Some rheumatoid arthritis, Crohn's disease, and psoriasis medications
- Undernourishment or a low body weight
- Extremely young or elderly
Traveling or residing in specific areas
You are more likely to contract tuberculosis if you live in, emigrate from, or travel to areas with high tuberculosis rates. Among these are:
- Africa
- Asia
- Eastern Europe
- Russia
- Latin America
Other factors
Using Substances: The use of IV drugs or excessive alcohol weakens your immune system, making you more susceptible to tuberculosis.
- Tobacco use: Tobacco use significantly increases the risk of contracting tuberculosis and dying from it.
- Working in the medical field: Contact with sick people on a regular basis increases your chances of contracting tuberculosis. Wearing a mask and washing your hands frequently reduces your risk significantly.
- Being a resident or employee of a residential care facility: Due to overcrowding and poor ventilation, people who live or work in prisons, homeless shelters, psychiatric hospitals, or nursing homes are all at a higher risk of tuberculosis.
- Living with a tuberculosis infected person: Close contact with someone infected with tuberculosis raises your risk.
WHAT ARE THE COMPLICATIONS OF TUBERCULOSIS?
Tuberculosis can be fatal if not treated. Untreated active disease typically affects the lungs, but it can also affect other parts of the body.
Complications of tuberculosis include:
- Spinal ache: Back pain and stiffness are common tuberculosis complications.
- Damage to the joints: Tuberculous arthritis (arthritis caused by tuberculosis) typically affects the hips and knees.
- Meningitis is a swelling of the membranes that cover your brain: This can result in a long-lasting or intermittent headache that lasts for weeks, as well as mental changes.
- Problems with the liver or kidneys: Your liver and kidneys aid in the removal of waste and impurities from your bloodstream. Tuberculosis in these organs has the potential to impair their functions.
- Heart disorders: In rare cases, tuberculosis can infect the tissues surrounding your heart, causing inflammation and fluid accumulations that can impair your heart's ability to pump effectively. This condition, known as cardiac tamponade, is potentially fatal.
HOW IS TUBERCULOSIS DIAGNOSED?
During the physical exam, your doctor will look for swelling in your lymph nodes and listen to the sounds your lungs make when you breathe.
A skin test is the most commonly used tuberculosis diagnostic tool, though blood tests are becoming more common. A small amount of tuberculin is injected just beneath the skin on the inside of your forearm. You should only feel a light prick from the needle.
A health care professional will check your arm for swelling at the injection site within 48 to 72 hours. A hard, raised red bump indicates that you have tuberculosis. The size of the bump determines whether or not the test results are statistically significant.
The outcomes may be incorrect.
The tuberculosis skin test isn't perfect. Sometimes it implies that people have tuberculosis when they do not. It can also imply that people do not have tuberculosis when they do.
If you've recently received the bacille Calmette-Guerin (BCG) vaccine, you may have a false-positive result. This tuberculosis vaccine is rarely used in the United States, but it is widely used in countries with high rates of tuberculosis infection.
False-negative results are also possible.
Blood tests
Blood tests can confirm or rule out tuberculosis, whether latent or active. These tests assess your immune system's response to tuberculosis bacteria.
These tests only necessitate one office visit. A blood test may be useful if you are at high risk of tuberculosis but have a negative skin test result, or if you have recently received the BCG vaccine.
Imaging tests
If you have a positive skin test, your doctor will almost certainly order a chest X-ray or a CT scan. This may reveal white spots in your lungs where your immune system has defended against TB bacteria, or it may reveal changes in your lungs caused by active tuberculosis.
Sputum tests
If your chest X-ray reveals tuberculosis, your doctor may take sputum samples — the mucus that comes up when you cough. The samples are tested for tuberculosis bacteria.
Sputum samples can also be tested for drug-resistant strains of tuberculosis. This assists your doctor in selecting the medications that are most likely to be effective. The results of these tests can take four to eight weeks to arrive.
WHAT ARE THE TREATMENTS OF TUBERCULOSIS?
If you have latent tuberculosis, your doctor may advise you to take medication if you are at high risk of developing active tuberculosis. Antibiotics must be taken for at least six to nine months if you have active tuberculosis.
The specific drugs and duration of treatment are determined by your age, overall health, potential drug resistance, and the location of the infection in your body.
The most commonly used TB medications
If you have latent tuberculosis, you may only need one or two types of TB drugs. Active tuberculosis will necessitate the use of multiple drugs at the same time, especially if the strain is drug-resistant. The following are the most commonly used tuberculosis medications:
- Isoniazid
- Rifabutin (Rifadin, Rimactane)
- Ethambutol (Myambutol)
- Pyrazinamide
If you have drug-resistant tuberculosis, a combination of fluoroquinolone antibiotics and injectable medications, such as amikacin or capreomycin (Capastat), is usually used for 20 to 30 months. Some types of tuberculosis are becoming resistant to these medications as well.
Some drugs may be added to therapy to combat drug resistance, such as:
- Bedaquiline (Sirturo)
- Linezolid (Zyvox)
Side effects of medication
Serious side effects of TB drugs are uncommon, but when they do occur, they can be deadly. All tuberculosis medications have the potential to be toxic to your liver. If you are taking these medications, contact your doctor right away if you experience any of the following symptoms:
- Vomiting or nausea
- Appetite loss
- A yellow color to your skin (jaundice)
- Dark urine
- Easy bruising or bleeding
- Blurred vision
Treatment must be completed.
After a few weeks, you will no longer be contagious and may begin to feel better. Do not discontinue your TB medications; you must complete the entire course of therapy and take the medications exactly as prescribed by your doctor.
Stopping treatment too soon or skipping doses may allow bacteria that are still alive to develop resistance to the drugs, resulting in TB that is much more dangerous and difficult to treat.
A program known as directly observed therapy (DOT) can assist people in sticking to their treatment plan. You are given your medication by a health care worker so that you do not have to remember to take it on your own.
HOW TO PREVENT TUBERCULOSIS?
If you test positive for latent tuberculosis infection, your doctor may advise you to take medications to lower your chances of developing active tuberculosis. Only active tuberculosis is contagious.
Safeguard your family and friends.
If you have active tuberculosis, it usually takes a few weeks of treatment with TB medications before you are no longer contagious. To help keep your friends and family from getting sick, follow these guidelines:
- Stay at home: During the first few weeks of treatment, avoid going to work, school, or sleeping in a room with other people.
- Ventilate the room: Tuberculosis germs spread more easily in small, closed spaces with no movement of air. Open the windows and use a fan to blow indoor air outside if it's not too cold outside.
- Cover your mouth: Cover your mouth with a tissue whenever you laugh, sneeze, or cough. Put the filthy tissue in a bag, seal it, and toss it.
Complete your medication
This is the single most important thing you can do to protect yourself and others from tuberculosis. When you discontinue or skip doses of TB treatment, the bacteria have a chance to develop mutations that allow them to survive the most potent TB drugs. Drug-resistant strains are more lethal and difficult to treat as a result.
Vaccinations
In countries where tuberculosis is more prevalent, infants are frequently immunized with the bacille Calmette-Guerin (BCG) vaccine. Because it is ineffective in adults, the BCG vaccine is not recommended for general use in the United States. Several new tuberculosis vaccines are in various stages of development and testing.
Put on a face mask: During the first three weeks of treatment, wearing a face mask when you're around other people may help reduce the risk of transmission.