At a Glance

Why Get Tested?

To help diagnose tuberculosis (TB) and infections caused by other Mycobacterium species, which are known as acid-fast bacilli (AFB), in people at risk of developing mycobacterial infections; to monitor the effectiveness of treatment

When To Get Tested?

When you have signs and symptoms of a lung infection, such as a chronic cough, weight loss, fever, chills, and weakness, that may be due to TB or a nontuberculous mycobacterial (NTM) infection; when you have a positive IGRA blood test or Tuberculin skin test (TST) and you are in a high-risk group for progressing to active TB; when you have a skin or other body site infection that may be due to mycobacteria; when you are undergoing treatment for TB

Sample Required?

For suspected cases of tuberculosis lung infections, usually three sputum samples are collected early in the morning on different days. If you are unable to produce sputum, a bronchoscope may be used to collect fluid during a procedure called a bronchoscopy. In children, gastric washings/aspirates may be collected. Depending on symptoms, urine, an aspirate from the site of suspected infection, cerebrospinal fluid (CSF), other body fluids, or biopsied tissue samples may be collected for AFB testing.

Test Preparation Needed?

None

Looking For Test Results?

Looking For Reference Ranges?

You may be able to find your test results on your laboratory’s website or patient portal. However, you are currently at Testing.com. You may have been directed here by your lab’s website in order to provide you with background information about the test(s) you had performed. You will need to return to your lab’s website or portal, or contact your healthcare practitioner in order to obtain your test results.

Testing.com is an award-winning patient education website offering information on laboratory tests. The content on the site, which has been reviewed by laboratory scientists and other medical professionals, provides general explanations of what results might mean for each test listed on the site, such as what a high or low value might suggest to your healthcare practitioner about your health or medical condition.

The reference ranges for your tests can be found on your laboratory report. They are typically found to the right of your results.

If you do not have your lab report, consult your healthcare provider or the laboratory that performed the test(s) to obtain the reference range.

Laboratory test results are not meaningful by themselves. Their meaning comes from comparison to reference ranges. Reference ranges are the values expected for a healthy person. They are sometimes called “normal” values. By comparing your test results with reference values, you and your healthcare provider can see if any of your test results fall outside the range of expected values. Values that are outside expected ranges can provide clues to help identify possible conditions or diseases.

While accuracy of laboratory testing has significantly evolved over the past few decades, some lab-to-lab variability can occur due to differences in testing equipment, chemical reagents, and techniques. This is a reason why so few reference ranges are provided on this site. It is important to know that you must use the range supplied by the laboratory that performed your test to evaluate whether your results are “within normal limits.”

For more information, please read the article Reference Ranges and What They Mean.

What is being tested?

Most samples that are submitted for acid-fast bacilli (AFB) testing are collected because the health care practitioner suspects that a person has tuberculosis (TB), a lung infection caused by Mycobacterium tuberculosis. Mycobacteria are called acid-fast bacilli because they are a group of rod-shaped bacteria (bacilli) that can be seen under the microscope following a staining procedure where the bacteria retain the color of the stain after an acid wash (acid-fast). AFB laboratory tests detect the bacteria in a person’s sample and help identify an infection caused by AFB.

There are several types of AFB that may be detected with this testing; however, the most common and medically important ones are members of the genus Mycobacterium. Mycobacterium tuberculosis is one of the most prevalent and infectious species of mycobacteria.

Since TB is transmitted through the air when an infected person sneezes, coughs, speaks, or sings, it is a public health risk. It can spread in confined populations, such as in the home and schools, correctional facilities, and nursing homes. Those who are very young, elderly, or have preexisting diseases and conditions, such as AIDS, that compromise their immune systems tend to be especially vulnerable. AFB testing can help diagnose, track, and minimize the spread of TB in these populations and help determine the effectiveness of treatment.

Another group of mycobacteria referred to as nontuberculous mycobacteria (NTM) can also cause infections. However, only a few of the more than 60 species of mycobacteria that have been identified cause infections in humans. Some examples include Mycobacterium avium-intracellulare complex (MAC), which can cause lung infection and disseminated disease in people with weakened immune systems. In addition to TB, AFB testing can help identify infections caused by these nontuberculous mycobacteria.

How is the sample collected for testing?

Sputum is the most commonly tested sample. Sputum is phlegm, thick mucus that is coughed up from the lungs. Preferably, three early morning samples obtained by deep cough are collected on consecutive days in individual sterile cups to increase the likelihood of detecting the bacteria.

If a person is unable to produce sputum, a health practitioner may collect respiratory samples using a procedure called a bronchoscopy. Bronchoscopy allows the health practitioner to look at and collect samples from the bronchi and bronchioles. Once a local anesthetic has been sprayed onto the patient’s upper airway, the practitioner can insert a tube into the bronchi and smaller bronchioles and aspirate fluid samples for testing. Sometimes, the healthcare practitioner will introduce a small amount of saline through the tubing and into the bronchi and then aspirate it to collect a bronchial washing.

Since young children cannot produce a sputum sample, gastric washings/aspirates may be collected. This involves introducing saline into the stomach through a tube, followed by fluid aspiration.

If the health care practitioners suspect TB is present outside of the lungs (extrapulmonary), they may test the body fluids and tissues most likely affected. For instance, one or more urine samples may be collected if the practitioner suspects TB has infected the kidneys. A needle may be used to collect fluid from joints or from other body cavities, such as the pericardium or abdomen. Occasionally, the practitioner may collect a sample of cerebrospinal fluid (CSF) or perform a minor surgical procedure to obtain a tissue biopsy.

Is any test preparation needed to ensure the quality of the sample?

No test preparation is needed, except to rinse the mouth with water before collecting the sputum sample.

Common Questions

How is it used?

AFB testing may be used to detect several different types of acid-fast bacilli, but it is most commonly used to identify an active tuberculosis (TB) infection.

Mycobacteria are called acid-fast bacilli because they are rod-shaped bacteria (bacilli) that can be seen under the microscope following a staining procedure in which the bacteria retain the color of the stain after an acid wash (acid-fast).

A few different tests may be used to help identify AFB as the cause of an infection:

AFB smear—a microscopic examination of a person’s sputum or other specimen that is stained to detect acid-fast bacteria. It is a rapid test used to provide presumptive results within one to two days. It is valuable in helping to make decisions about treatment while waiting for culture results. However, AFB smears must be confirmed with AFB cultures.
Molecular tests for TB (nucleic acid amplification test or NAAT) detect the genetic material of mycobacteria. These tests are often used when the AFB smear is positive or TB is highly suspected. Like AFB smears, they can provide a presumptive diagnosis, which can aid in the decision of whether to begin treatment and isolate potentially infectious people before culture results are available. Results of NAAT are typically available in one to three days after a sample is collected. Molecular methods are approved for use with respiratory samples but must be confirmed with an AFB culture. Guidelines from the Centers for Disease Control and Prevention recommend that people with signs and symptoms of TB have at least one sample tested using nucleic acid amplification with AFB smear and culture. The NAAT test currently available is done directly on sputum samples and can simultaneously detect TB and its resistance to rifampicin in less than two hours. Rifampicin is a common treatment for TB.
AFB cultures are used to diagnose active M. tuberculosis infections as well as infections due to nontuberculous mycobacteria. AFB cultures can also be used to monitor the effectiveness of treatment and can help determine when a person is no longer infectious. Though culture is more sensitive than an AFB smear, positive results may take days to several weeks, while negative culture results (no mycobacterial growth) can take up to 6 to 8 weeks to confirm.
Susceptibility testing is usually ordered in conjunction with an AFB culture to determine the most effective antibiotic to treat the mycobacterial infection. M. tuberculosis may be resistant to one or more drugs commonly used to treat TB.

When is it ordered?

AFB testing is ordered when:

Someone has signs and symptoms that suggest an active TB lung infection (pulmonary) or other mycobacterial lung infection, such as:
- Lingering, chronic cough that produces phlegm or sputum, sometimes with bloody streaks
- Fever, chills
- Night sweats
- Loss of appetite
- Unexplained weight loss
- Weakness, fatigue
- Chest pain
A person has symptoms associated with a TB or other mycobacterial infection located outside of the lungs (extrapulmonary); the symptoms vary depending on the area of the body that is affected. Some examples include back pain and paralysis (spinal TB), weakness due to anemia (TB in the bone marrow), altered mental state, headache, and coma (TB meningitis), joint pain or abdominal pain.
A TB screening test is positive and the person is at increased risk for active disease and/or characteristic signs are seen in an X-ray of the lung; there are two types of tests that are used to determine if a person has had contact or is infected with M. tuberculosis: the tuberculin test (TST) and the blood test (IGRA).
Someone has been in close contact with a person who has been diagnosed with TB and the exposed person either has symptoms or has a condition or disease, such as HIV, that puts the person at a much higher risk of contracting active TB.
An individual is being treated for TB; AFB testing is usually ordered at intervals, both for evaluating the effectiveness of treatment and for determining whether or not a person is still infectious.
An individual has a chronic skin infection that does not respond to the usual antibiotics given for a bacterial infection; NTM may be the cause of the infection since they do not respond to the same antibiotics used to treat a staphylococcal or streptococcal infection.

What does the test result mean?

AFB Smear and NAAT
A negative AFB smear may mean that no infection is present, that symptoms are caused by something other than mycobacteria, or that the mycobacteria were not present in sufficient numbers to be seen under the microscope. Usually three samples are collected to increase the probability that the organisms will be detected.

Nevertheless, if AFB smears are negative and there is still a strong suspicion of a mycobacterial infection, then additional samples may be collected and tested on different days. A smear negative sample may still grow mycobacteria since the culture media allows low numbers of bacteria that cannot be seen in a microscopic examination to multiply and be detected.

Positive AFB smears indicate a probable mycobacterial infection. However, a culture must be performed to confirm a diagnosis and identify the species of mycobacteria present.

For people with signs and symptoms of an active TB infection, AFB smear results are considered together with results from NAAT for TB, as recommended by the Centers for Disease Control and Prevention. Though definitive diagnosis requires results from a culture, results from the smear and NAAT may be helpful in deciding what to do. For example, if there is a presumptive diagnosis of TB based on rapid test results, most health practitioners would treat.

Interpretation of smear and NAAT results are summarized in the following table. Again, all results must be confirmed by results from culture.

AFB smear result	NAAT result for TB	Interpretation
Positive	Positive	Presumptive diagnosis for TB
Negative	Positive	NAAT is more sensitive than an AFB smear so this may occur in people with true disease; may test additional samples using NAAT. If more than one sample is positive by NAAT, this is a presumptive diagnosis for TB.
Positive	Negative	Questionable results for TB; the AFB seen on the smear are not M. tuberculosis.
Negative	Negative	Symptoms probably not due to active mycobacterial infection.

AFB Culture
Positive AFB cultures identify the particular mycobacterium causing symptoms, and susceptibility testing on the identified organism gives the healthcare practitioner information about how resistant it may be to treatment.

A positive AFB smear or culture several weeks after drug treatment has started may mean that the treatment regimen is not effective and needs to be changed. It also means that the person is still likely to be infectious and can pass the mycobacteria to others through coughing or sneezing.

A negative culture means that the person tested does not have an active AFB infection or that mycobacteria were not present in that particular sample (which is why multiple samples are often collected) or were present in numbers too low to be detected. Cultures are held for six to eight weeks before being reported as negative. The person tested may have a latent infection that caused a TB screening test to be positive but does not have active TB.

If it is suspected that someone has a TB infection that has spread to another part of the body, a sample from the site of suspected infection may need to be collected and tested to identify the infection.

A negative culture several weeks after treatment indicates that the TB infection is responding to drug treatment and that the person is no longer infectious.

Susceptibility Testing
Susceptibility testing results will list the antibiotics that will likely be most effective in treating the infection. Isoniazid and rifampin are two drugs commonly used to treat TB. If the bacteria are resistant to more than one or the primary drugs used for therapy, the organisms are called multidrug-resistant TB (MDR-TB), and if the organisms are resistant to multiple drugs approved for first and second lines of therapy, they are called extensively drug-resistant tuberculosis (XDR-TB).

Is there anything else I should know?

TB requires a lengthy course of multiple antibiotics to cure an active infection. People with inactive (latent) infections, although asymptomatic, may be treated with a single drug to reduce the risk of having an active infection in the future.

A faster lab method to culture Mycobacterium tuberculosis has been developed. Culturing the sample in a liquid broth-based medium allows the organisms to be detected sooner. Some of the broth cultures require an automated instrument to detect the presence of the mycobacteria, while other methods can be read manually. A liquid culture method, called Microscopic-Observation Drug-Susceptibility (MODS) assay, takes only about 7 days to diagnose TB and detects bacterial resistance to antibiotics at the same time. Since this method can recognize the presence of multidrug-resistant TB (MDR-TB) much more quickly than conventional culture, it can help health practitioners diagnose and treat the disease at an earlier stage and has the potential to help control the spread of infectious TB. The benefits and limitations of this non-automated test are still being evaluated in resource-limited countries with high prevalence of TB.

There are other new methods being used in some laboratories that can identify M. tuberculosis very rapidly and accurately once the mycobacteria is growing in culture.

Can I have a tuberculosis (TB) infection and not be sick?

Yes. There are many people in the United States and worldwide who have a latent form of TB infection. They have been exposed to the bacteria, but their body’s immune system has confined it to a localized area in their lungs, in an inactive form. People with latent TB infections are not sick and they are not infectious, but the bacteria are still there and still alive. If those with latent infections are tested, most would have a positive TB skin test or IGRA test. The majority of people with latent TB infection, about 90%, will never progress to active tuberculosis disease.

Those who do have active TB may not feel ill at first. Early symptoms may be subtle and, if the TB is extrapulmonary (outside of the lungs in organs such as the kidney and bone), the tuberculosis may be fairly advanced by the time it causes noticeable symptoms.

What is the difference between multidrug-resistant TB (MDR-TB) and extensively-resistant TB (XDR-TB)?

Both indicate strains of Mycobacteria tuberculosis that can be difficult to treat, but XDR-TB is resistant to more drug therapies. MDR-TB is resistant to the two most powerful drugs, isoniazid and rifampin. XDR-TB is currently defined by the Centers for Disease Control and Prevention and the World Health Organization as M. tuberculosis that is resistant to isoniazid and rifampin plus resistant to any fluoroquinolone and to at least one of three injectable “second-line” drugs (amikacin, kanamycin, or capreomycin). The emergence of XDR-TB represents a public health risk and is being closely watched by the world medical community and measures are being taken in hopes of limiting its spread.

Why is my healthcare provider asking me to take my TB medication in the presence of a nurse?

The practice of taking TB medications in the presence of a health care practitioner is known as direct observed therapy (DOT). DOT ensures that people are taking their medications and continuing their therapy for the required length of time. Unlike other bacterial infections that can be cured in 7-10 days, TB must be treated with two or more drugs for several months. People tend to forget to take their medication when they are feeling better. Since TB medications must be taken for many months, the risk of non-compliance is high. Having a healthcare practitioner administer the medications weekly increases the likelihood that the entire regimen will be completed and decreases the likelihood that someone will relapse with a more resistant strain of TB.

Besides TB, what other types of mycobacteria can be identified with AFB testing?

Examples of other mycobacteria that can cause infections and are detected using AFB tests include:

Mycobacterium avium-intracellulare complex (MAC)—can cause a lung infection in people with weakened immune systems, such as those with AIDS; this infection is not contagious but it can be difficult to treat as it tends to be highly resistant to antibiotics.
Mycobacterial species, such as Mycobacterium marinum, grow in water, such as fish tanks, and can cause skin infections.
Mycobacterium fortuitum, Mycobacterium abscessus and Mycobacterium chelonae, and other rapidly growing mycobacteria, cause skin and wound infections following cosmetic surgery, prosthetic device implantation, and visits to nail salons.
A few mycobacteria, such as Mycobacterium bovis, can sometimes be transferred from animals to humans.

Nocardia species are not a type of mycobacteria but can be detected using some AFB laboratory tests. Nocardia can cause infections of the lungs, brain, or skin.

Related Images

Mycobacterium tuberculosis, the cause of TB. Image credit: National Institute of Allergies and Infectious Diseases
Acid fast bacteria as seen under a microscope. Image credit: CDC

Health Professionals – LOINC

regesnstrief logo LOINC Observation Identifiers Names and Codes (LOINC®) is the international standard for identifying health measurements, observations, and documents. It provides a common language to unambiguously identify things you can measure or observe that enables the exchange and aggregation of clinical results for care delivery, outcomes management, and research. Learn More.

Listed in the table below are the LOINC with links to the LOINC detail pages. Please note when you click on the hyperlinked code, you are leaving Testing.com and accessing Loinc.org.

LOINC	LOINC Display Name
20893-4	M. avium ss paratuberculosis Org specific cx Ql (Stl)
20892-6	M. avium ss paratuberculosis Org specific cx Ql (Tiss)
24427-7	M. avium ss paratuberculosis Org specific cx Ql (Unsp spec)
90433-4	Mycobacterium preliminary growth Org specific cx Ql (Sput)
90438-3	Mycobacterium preliminary growth Org specific cx Ql (Tiss)
44851-4	Mycobacterium sp identified # 2 Org specific cx Nom (Unsp spec)
44852-2	Mycobacterium sp identified # 3 Org specific cx Nom (Unsp spec)
44854-8	Mycobacterium sp identified # 4 Org specific cx Nom (Unsp spec)
44855-5	Mycobacterium sp identified # 5 Org specific cx Nom (Unsp spec)
532-2	Mycobacterium sp identified Org specific cx Nom (Asp)
76687-3	Mycobacterium sp identified Org specific cx Nom (BAL)
90284-1	Mycobacterium sp identified Org specific cx Nom (Bile)
533-0	Mycobacterium sp identified Org specific cx Nom (Bld)
9823-6	Mycobacterium sp identified Org specific cx Nom (Bronch spec)
88167-2	Mycobacterium sp identified Org specific cx Nom (Corn/Cnjt)
534-8	Mycobacterium sp identified Org specific cx Nom (CSF)
30045-9	Mycobacterium sp identified Org specific cx Nom (Dial fld)
535-5	Mycobacterium sp identified Org specific cx Nom (Body fld)
9824-4	Mycobacterium sp identified Org specific cx Nom (Gast fld)
89637-3	Mycobacterium sp identified Org specific cx Nom (Implanted device)
9825-1	Mycobacterium sp identified Nom (Isol)
536-3	Mycobacterium sp identified Org specific cx Nom (BM)
88168-0	Mycobacterium sp identified Org specific cx Nom (Ocular fluid)
53909-8	Mycobacterium sp identified Org specific cx Nom (Pleur fld)
537-1	Mycobacterium sp identified Org specific cx Nom (Periton fld)
89636-5	Mycobacterium sp identified Org specific cx Nom (Lower resp)
538-9	Mycobacterium sp identified Org specific cx Nom (Syn fld)
539-7	Mycobacterium sp identified Org specific cx Nom (Sput)
540-5	Mycobacterium sp identified Org specific cx Nom (Tiss)
541-3	Mycobacterium sp identified Org specific cx Nom (U)
542-1	Mycobacterium sp identified Org specific cx Nom (Wound)
543-9	Mycobacterium sp identified Org specific cx Nom (Unsp spec)
64412-0	Mycobacterium sp Org specific cx Ql (Bld)
50941-4	Mycobacterium sp Org specific cx Ql (Unsp spec)
79375-2	Microscopic observation spec 2 Acid fast stain.Ziehl-Neelsen Nom (Sput)
79376-0	Microscopic observation spec 3 Acid fast stain.Ziehl-Neelsen Nom (Sput)
88156-5	Microscopic observation Acid fast stain Nom (Amn fld)
88159-9	Microscopic observation Acid fast stain Nom (Asp)
88231-6	Microscopic observation Acid fast stain Nom (Bile)
32699-1	Microscopic observation Acid fast stain Nom (Bld)
24002-8	Microscopic observation Acid fast stain Nom (Bronch spec)
58943-2	Microscopic observation Acid fast stain.Ziehl-Neelsen Nom (CSF)
32188-5	Microscopic observation Acid fast stain Nom (CSF)
89582-1	Microscopic observation Acid fast stain Nom (Cvx)
58944-0	Microscopic observation Acid fast stain.Ziehl-Neelsen Nom (Body fld)
32189-3	Microscopic observation Acid fast stain Nom (Body fld)
641-1	Microscopic observation Acid fast stain.Kinyoun modified Nom (Gast fld)
642-9	Microscopic observation Acid fast stain.Ziehl-Neelsen Nom (Gast fld)
11476-9	Microscopic observation Acid fast stain Nom (Gast fld)
88148-2	Microscopic observation Acid fast stain Nom (Genital specimen)
89660-5	Microscopic observation Acid fast stain Nom (Implanted device)
88153-2	Microscopic observation Acid fast stain Nom (BM)
90269-2	Microscopic observation Acid fast stain Nom (Milk)
88155-7	Microscopic observation Acid fast stain Nom (Ocular fluid)
88145-8	Microscopic observation Acid fast stain Nom (Pericard fld)
14353-7	Microscopic observation Acid fast stain.Kinyoun modified Nom (Pleur fld)
58942-4	Microscopic observation Acid fast stain.Ziehl-Neelsen Nom (Pleur fld)
58945-7	Microscopic observation Acid fast stain.Ziehl-Neelsen Nom (Periton fld)
88144-1	Microscopic observation Acid fast stain Nom (Periton fld)
89662-1	Microscopic observation Acid fast stain Nom (Lower resp)
89661-3	Microscopic observation Acid fast stain Nom (Upper resp)
88154-0	Microscopic observation Acid fast stain Nom (Sinus)
88157-3	Microscopic observation Acid fast stain Nom (Sem)
63433-7	Microscopic observation Acid fast stain.Ziehl-Neelsen Nom (Syn fld)
646-0	Microscopic observation Acid fast stain.Kinyoun modified Nom (Sput)
647-8	Microscopic observation Acid fast stain.Ziehl-Neelsen Nom (Sput)
11477-7	Microscopic observation Acid fast stain Nom (Sput)
11478-5	Microscopic observation Acid fast stain Nom (Stl)
6656-3	Microscopic observation Acid fast stain.Kinyoun modified Nom (Tiss)
6657-1	Microscopic observation Acid fast stain.Ziehl-Neelsen Nom (Tiss)
11479-3	Microscopic observation Acid fast stain Nom (Tiss)
651-0	Microscopic observation Acid fast stain.Kinyoun modified Nom (U)
652-8	Microscopic observation Acid fast stain.Ziehl-Neelsen Nom (U)
11480-1	Microscopic observation Acid fast stain Nom (U)
14354-5	Microscopic observation Acid fast stain.Kinyoun modified Nom (Wound)
88151-6	Microscopic observation Acid fast stain Nom (Wound)
655-1	Microscopic observation Acid fast stain.Kinyoun modified Nom (Unsp spec)
656-9	Microscopic observation Acid fast stain.Ziehl-Neelsen Nom (Unsp spec)
11545-1	Microscopic observation Acid fast stain Nom (Unsp spec)
76083-5	Microscopic observation Acid fast stain.Ziehl-Neelsen Ql (BAL)
88171-4	Microscopic observation Acid fast stain Ql (Corn/Cnjt)
88172-2	Microscopic observation Acid fast stain Ql (Isol)
88173-0	Microscopic observation Acid fast stain Ql (Pleur fld)
88234-0	Microscopic observation Acid fast stain Ql (Syn fld)
88366-0	Microscopic observation Acid fast stain Ql (Vomitus)
72357-7	Microscopic observation Acid fast stain Ql (Unsp spec)
23243-9	M. avium ss paratuberculosis Acid fast stain.Ziehl-Neelsen Ql (Stl)
23244-7	M. avium ss paratuberculosis Acid fast stain.Ziehl-Neelsen Ql (Tiss)
85581-7	M. avium and M. intracellulare DNA NAA+probe Nom (Sput/Bronchial)
71719-9	M. avium complex DNA NAA+probe Ql (Unsp spec)
20463-6	M. avium complex rRNA NAA+probe Ql (Unsp spec)
23246-2	M. avium ss paratuberculosis DNA NAA+probe Ql (Stl)
23245-4	M. avium ss paratuberculosis DNA NAA+probe Ql (Unsp spec)
45116-1	M. gordonae rRNA NAA+probe Ql (Unsp spec)
45117-9	M. kansasii rRNA NAA+probe Ql (Unsp spec)
21405-6	Mycobacterium sp DNA NAA+probe Ql (Bronch spec)
14972-4	Mycobacterium sp DNA NAA+probe Ql (CSF)
14973-2	Mycobacterium sp DNA NAA+probe Ql (Sput)
23247-0	Mycobacterium sp DNA NAA+probe Ql (Tiss)
30523-5	Mycobacterium sp DNA NAA+probe Ql (U)
14974-0	Mycobacterium sp DNA NAA+probe Ql (Unsp spec)
42716-1	Mycobacterium sp rRNA NAA+probe Nar (Isol)
85362-2	M. tuberculosis complex DNA NAA+probe Ql (Sput/Bronchial)
38379-4	M. tuberculosis complex DNA NAA+probe Ql (Unsp spec)
48174-7	M. tuberculosis complex rRNA NAA+probe Ql (Unsp spec)
46244-0	M. tuberculosis DNA rpoB NAA+probe Nom (Isol)
53257-2	M. tuberculosis DNA NAA+probe (Unsp spec) [#/Vol]
78357-1	M. tuberculosis DNA NAA+probe Ql (BAL)
90283-3	M. tuberculosis DNA NAA+probe Ql (Bile)
16278-4	M. tuberculosis DNA NAA+probe Ql (Bld)
14557-3	M. tuberculosis DNA NAA+probe Ql (Bronch spec)
88165-6	M. tuberculosis DNA NAA+probe Ql (Corn/Cnjt)
14561-5	M. tuberculosis DNA NAA+probe Ql (CSF)
58931-7	M. tuberculosis DNA NAA+probe Ql (Body fld)
14558-1	M. tuberculosis DNA NAA+probe Ql (Gast fld)
89635-7	M. tuberculosis DNA NAA+probe Ql (Implanted device)
88166-4	M. tuberculosis DNA NAA+probe Ql (Ocular fluid)
14559-9	M. tuberculosis DNA NAA+probe Ql (Pleur fld)
14562-3	M. tuberculosis DNA NAA+probe Ql (Sem)
14556-5	M. tuberculosis DNA NAA+probe Ql (Sput)
14560-7	M. tuberculosis DNA NAA+probe Ql (U)
13956-8	M. tuberculosis DNA NAA+probe Ql (Unsp spec)
33634-7	M. tuberculosis rifampin resistance gene NAA+probe Nom (Sput)

View Sources

Sources Used in Current Review

Lewinsohn, D, et. al. (2017 January 03). Official American Thoracic Society/Infectious Diseases Society of America/Centers for Disease Control and Prevention Clinical Practice Guidelines: Diagnosis of Tuberculosis in Adults and Children. Clinical Infectious Diseases, Volume 64, Issue 2, 15 January 2017, Pages 111–115. Available online at https://academic.oup.com/cid/article/64/2/111/2811357. Accessed on 8/05/18.

Vyas, J. et. al. (2016 November 14, Updated). Sputum stain for mycobacteria. MedlinePlus Medical Encyclopedia. Available online at https://medlineplus.gov/ency/article/003724.htm. Accessed on 8/05/18.

Koirala, J. (2017 November 14, Updated). Mycobacterium Avium Complex (MAC) (Mycobacterium Avium-Intracellulare [MAI]). Medscape Infectious Diseases. Available online at https://emedicine.medscape.com/article/222664-overview. Accessed on 8/05/18.

Herchline, T. and Amorosa, J. (2017 November 9, Updated). Tuberculosis (TB). Medscape Infectious Diseases. Available online at https://emedicine.medscape.com/article/230802-overview. Accessed on 8/05/18.

Batra, V. and Ang, J. (2018 April 26, Updated). Pediatric Tuberculosis. Medscape Pediatrics: General Medicine. Available online at https://emedicine.medscape.com/article/969401-overview. Accessed on 8/05/18.

Barker, A. (2018 July, Updated). Mycobacterium tuberculosis – Tuberculosis. ARUP Consult. Available online at https://arupconsult.com/content/mycobacterium-tuberculosis. Accessed on 8/05/18.

Sources Used in Previous Reviews

Thomas, Clayton L., Editor (1997). Taber’s Cyclopedic Medical Dictionary. F.A. Davis Company, Philadelphia, PA [18th Edition].

Pagana, Kathleen D. & Pagana, Timothy J. (2001). Mosby’s Diagnostic and Laboratory Test Reference 5th Edition: Mosby, Inc., Saint Louis, MO.

Heimerdinger, M. (2000). Tuberculosis. ACP-ASIM [On-line session report]. Available online at http://www.acponline.org/vas2000/sessions/tb.htm.

Kirchner, J. (2000 February 1). Do Sputum Smears Positive for AFB Signify Treatment Failure? American Family Physician [On-line journal]. Available online at http://www.aafp.org/afp/20000201/tips/25.html.

Jerant, A. et.al. (2000 May 1). Identification and Management of Tuberculosis. American Family Physician [On-line journal]. Available online at http://www.aafp.org/afp/20000501/2667.html.

Sadovsky, R. (2001 May 15). Making the Diagnosis of Tuberculosis in Children. American Family Physician [On-line journal]. Available online at http://www.aafp.org/afp/20010515/tips/9.html.

Centers for Disease Control and Prevention (2002 August 13, Reviewed). Frequently Asked Questions, Questions and Answers about TB. National Center for HIV, STD and TB Prevention Division of Tuberculosis Elimination [On-line information]. Available online at http://www.cdc.gov/nchstp/tb/faqs/qa.htm.

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Acid-Fast Bacillus (AFB) Testing