What Is Tuberculosis?
Tuberculosis (TB) is an infection caused by Mycobacterium tuberculosis. It most often affects the lungs but can also involve the lymph nodes, spine, kidneys, brain, and other parts of the body. TB spreads through the air when a person with infectious TB disease of the lungs or throat coughs, speaks, or otherwise releases bacteria-containing particles into the air. Not everyone who becomes infected develops active TB disease, and effective treatment is available for both inactive TB infection and active TB disease.
Symptoms of Tuberculosis
Symptoms occur with active TB disease and depend on where in the body the infection is located. Pulmonary TB, which affects the lungs, often develops gradually and can cause a persistent cough, chest discomfort, fatigue, fever, night sweats, loss of appetite, and unexplained weight loss. Some people may cough up sputum or blood.
People with inactive TB infection, also called latent TB infection, have TB bacteria in the body but do not have symptoms and cannot spread TB to other people. Without treatment, inactive TB can later develop into active TB disease, particularly when the immune system becomes less able to keep the bacteria under control.
Persistent Cough
A cough lasting three weeks or longer is a common symptom of pulmonary TB. The cough may produce sputum, and in some cases blood may be present.
Chest Pain or Shortness of Breath
TB affecting the lungs can cause chest pain and, in some patients, shortness of breath. These symptoms can occur with many other lung conditions, so additional evaluation is needed to determine the cause.
Fever and Chills
Active TB disease can cause fever and chills. Symptoms may develop gradually and can persist for weeks before a person seeks medical attention.
Fatigue
Weakness, fatigue, and a general loss of energy are common systemic symptoms of active TB disease and may become more noticeable as the illness progresses.
Loss of Appetite and Weight Loss
Active TB can reduce appetite and lead to unintended weight loss. Persistent or unexplained weight loss should be evaluated along with other symptoms and risk factors.
Night Sweats
Night sweats are another common symptom of active TB disease and may occur along with fever, fatigue, and weight loss.
How Is Tuberculosis Diagnosed?
Diagnosing tuberculosis involves determining whether a person has been infected with TB bacteria and, when infection or symptoms are present, whether the person has inactive TB infection or active TB disease. A complete evaluation may include medical history, physical examination, a TB blood or skin test, chest imaging, and laboratory testing of sputum or other specimens.
People with symptoms suggestive of active TB disease should be evaluated promptly. A TB blood test or skin test alone cannot determine whether TB infection is inactive or has progressed to active disease.
TB Blood Test (IGRA)
Interferon-gamma release assays (IGRAs) are blood tests that measure the immune system’s response to TB bacteria. They can identify TB infection but cannot by themselves distinguish inactive TB infection from active TB disease.
IGRAs are often preferred for people who have received the BCG tuberculosis vaccine because the vaccine does not cause a positive IGRA result.
Tuberculin Skin Test (TST)
The tuberculin skin test, also called the Mantoux test, can also identify TB infection. A small amount of testing material is placed under the skin of the forearm, and the injection site is examined by a healthcare professional 48 to 72 hours later.
As with an IGRA, a positive skin test indicates TB infection but does not establish whether the infection is active.
Chest X-Ray
A chest X-ray is commonly used when active pulmonary TB is suspected or when a person has a positive test for TB infection. It can reveal abnormalities such as areas of inflammation, cavities, or other changes that may suggest active or previous TB, although imaging alone cannot confirm the diagnosis.
Chest CT Scan
A CT scan provides more detailed images of the lungs and chest than a standard X-ray. It may be useful when chest X-ray findings are unclear, when complications are suspected, or when physicians need more detailed information about the location and extent of disease.
Sputum and Laboratory Testing
When pulmonary TB disease is suspected, sputum samples are tested directly for evidence of Mycobacterium tuberculosis. Laboratory evaluation can include microscopic examination, nucleic-acid amplification testing (NAAT), and culture.
NAAT can provide rapid evidence that TB bacteria are present, while culture remains an important confirmatory test and allows additional testing to determine which medications are most likely to be effective. More than one sputum specimen is generally collected because this improves the ability to detect TB bacteria.
Drug-Susceptibility Testing
If TB bacteria are identified, laboratory testing can determine whether they are resistant to commonly used TB medications. This information helps physicians select an effective treatment regimen and is especially important because drug-resistant forms of tuberculosis require different therapy.
Tuberculosis Treatment
Tuberculosis is treated with medications that kill Mycobacterium tuberculosis and help prevent the development of drug resistance. The specific treatment depends on whether a person has inactive TB infection or active TB disease, whether the bacteria are susceptible to standard medications, the location and severity of disease, other medical conditions, and possible interactions with medications the patient is already taking.
Completing the prescribed course of treatment is essential. Stopping medications too early or missing doses can allow TB bacteria to survive, contribute to treatment failure, and increase the risk of drug-resistant tuberculosis.
Treatment for Inactive TB Infection
People with inactive TB infection do not have symptoms and cannot spread TB to others, but treatment can prevent the infection from progressing to active TB disease. Before treatment for inactive TB begins, active TB disease should be excluded.
Several treatment regimens are available. Short-course regimens lasting three or four months are often preferred when appropriate because they are effective and may be easier to complete. The choice of medication and treatment duration depends on a person’s health history, age, potential medication interactions, and other individual factors.
Treatment for Active TB Disease
Active tuberculosis is treated with a combination of medications because using multiple drugs helps eliminate TB bacteria and reduce the likelihood of drug resistance. Treatment for drug-susceptible TB disease may last four, six, or nine months depending on the regimen and the patient’s individual circumstances.
Common medications used in TB treatment include isoniazid, rifampin, rifapentine, pyrazinamide, ethambutol, and, in selected regimens, moxifloxacin. The appropriate combination is determined by the type of TB, drug-susceptibility results, other health conditions, and potential medication interactions.
Directly Observed Therapy (DOT)
Directly observed therapy helps patients complete treatment by having a healthcare professional observe medication doses, monitor for side effects, and provide ongoing support. DOT may be provided in person or through video directly observed therapy (vDOT), allowing treatment observation using a smartphone, tablet, or computer when appropriate.
Drug-Resistant Tuberculosis
Drug-resistant TB occurs when tuberculosis bacteria are resistant to one or more of the medications normally used to treat the disease. Treatment requires specialized drug-susceptibility testing and a regimen selected specifically for the resistance pattern identified.
Newer treatment approaches have made shorter, all-oral regimens possible for many eligible patients with drug-resistant TB. Because treatment can be complex, drug-resistant tuberculosis should be managed by or in close consultation with clinicians experienced in treating the disease and coordinated with public health specialists.
Monitoring During Treatment
Patients are monitored during TB treatment to make sure the medications are working and to identify potential side effects. Follow-up may include clinical evaluation, laboratory testing, chest imaging, and additional sputum testing depending on the type and extent of disease.
When Is Surgery Used for Tuberculosis?
Surgery is not routinely needed to treat tuberculosis because most patients can be treated successfully with appropriate medical therapy. Thoracic surgery may have a role in selected patients when TB has caused significant structural damage or complications, when diagnosis cannot be established through less invasive methods, or as part of the management of difficult drug-resistant disease.
Drug-Resistant or Persistent Disease
In carefully selected patients with localized drug-resistant TB that does not respond adequately to medical therapy, removal of severely affected lung tissue may be considered as an addition to an effective medication regimen. These decisions require specialized multidisciplinary evaluation.
Complications of Tuberculosis
TB can cause lasting damage to the lungs and airways, including bronchiectasis, cavities, airway narrowing, bleeding, or destruction of lung tissue. Surgery may occasionally be considered when these complications cause serious or persistent problems that cannot be adequately managed with other treatments.
Surgery for Diagnosis
Most pulmonary TB can be diagnosed using imaging and laboratory testing of sputum or other specimens. In uncommon situations when the diagnosis remains uncertain, bronchoscopy, needle biopsy, or a surgical biopsy may be needed to obtain tissue for laboratory and pathologic examination.
Thoracic Surgery
When surgery is necessary, the procedure depends on the location and extent of lung damage. Selected patients may require removal of a portion of the lung, such as a segmentectomy or lobectomy, while more extensive surgery is rarely necessary. Surgery complements rather than replaces effective anti-tuberculosis medication.
Tuberculosis treatment combines medical care with public health measures designed to cure the infection and prevent transmission to others. Treatment plans may involve pulmonologists, infectious disease specialists, public health professionals, pharmacists, and thoracic surgeons when complications or surgical evaluation are involved.
At Providence Saint John’s Health Center, patients with complex pulmonary conditions can receive coordinated evaluation and treatment based on the type and extent of lung disease and their individual medical needs. Call today to learn more about tuberculosis evaluation and treatment. Our multidisciplinary team is ready to support you.
If you have questions about Tuberculosis symptoms or diagnosis, please call today. Click here to request an appointment.
