Medically reviewed by Drugs.com. Last updated on May 23, 2019.
(too BER kyoo lin tests)
- TB Skin Test
- Tuberculin Purified Protein Derivative
- Tuberculin Skin Test
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Aplisol: 5 units/0.1 mL (1 mL, 5 mL) [latex free; contains phenol, polysorbate 80]
Tubersol: 5 units/0.1 mL (1 mL, 5 mL) [contains phenol, polysorbate 80]
Brand Names: U.S.
- Diagnostic Agent
Tuberculosis results in individuals becoming sensitized to certain antigenic components of the M. tuberculosis organism. Culture extracts called tuberculins are contained in tuberculin skin test preparations. Upon intracutaneous injection of these culture extracts, a classic delayed (cellular) hypersensitivity reaction occurs. This reaction is characteristic of a delayed course (peak occurs >24 hours after injection, induration of the skin secondary to cell infiltration, and occasional vesiculation and necrosis). Delayed hypersensitivity reactions to tuberculin may indicate infection with a variety of nontuberculosis mycobacteria, or vaccination with the live attenuated mycobacterial strain of M. bovis vaccine, BCG, in addition to previous natural infection with M. tuberculosis.
Onset of Action
Delayed hypersensitivity reactions: 5-6 hours; Peak effect: 48-72 hours
Duration of Action
Reactions subside over a few days
Use: Labeled Indications
Tuberculosis skin test: An aid in the diagnosis of tuberculosis (TB) infection.
Hypersensitivity to tuberculin purified protein derivative (PPD) or any component of the formulation; previous severe reaction to tuberculin PPD skin test (TST); documented active TB or clear history of treatment for TB infection or disease; extensive burns or eczema.
Note: Dosing below is based on US/Canadian products which contain the PPD-S formulation; in regions outside of North America other products may be used, including the RT 23 formulation, and standard doses may differ between products as the units are not equivalent (Yang 2012).
Tuberculin skin test: Intradermal: 5 units (0.1 mL)
TST interpretation: Criteria for positive TST read at 48 to 72 hours (see Note below for health care workers; CDC 2000):
Induration ≥5 mm: Patients with HIV infection (or risk factors for HIV infection, but unknown status), recent close contact to person with known active TB, patients with chest x-ray consistent with prior TB, patients with organ transplants and other immunosuppressed patients (receiving the equivalent of prednisone ≥15 mg/day for ≥1 month
Induration ≥10 mm: Patients with clinical conditions that increase risk of TB infection, recent immigrants (ie, ≤5 years) from high-prevalence countries, IV drug users, residents and employees of high-risk congregate settings, mycobacteriology laboratory workers, children <4 years of age, or infants, children, and adolescents exposed to adults at high risk
Induration ≥15 mm: Patients who do not meet any of the above criteria (no risk factors for TB)
Note: A two-step test is recommended when testing will be performed at regular intervals (eg, for health care workers). If the first test is negative, a second TST should be administered 1 to 3 weeks after the first test was read.
TST interpretation (CDC guidelines) in a health care setting (CDC 2005):
Baseline test: ≥10 mm is positive (either first or second step); 0 to 9 mm is negative
Serial testing without known exposure: Increase of ≥10 mm is positive
≥5 mm is positive in patients with baseline of 0 mm
≥10 mm is positive in patients with negative baseline or previous screening result of >0 mm
Refer to adult dosing.
Tuberculin skin test: Intradermal: Infants ≥6 months, Children, and Adolescents: Refer to adult dosing.
For intradermal administration only; do not administer IV, IM, or SubQ. Administer to upper third of forearm (palm up) ≥2 inches from elbow, wrist, or other injection site. If neither arm can be used, may administer to back of shoulder (CDC 2005). Avoid skin that is red or swollen; avoid visible veins. Administer using 1/4- to 1/2-inch 27-gauge needle or finer tuberculin syringe (CDC 2005). Should form wheal (6 to 10 mm in diameter) as liquid is injected which will remain ~10 minutes. Avoid pressure or bandage at injection site. Should wheal fail to form, repeat the test immediately at another site, at least 2 inches from the first site and circle the second injection site as an indication that this is the site to be read. Document date and time of injection, person placing TST, location of injection site, and lot number of solution. Read test at 48 to 72 hours following placement. Test results should be documented in millimeters even if classified as negative. Erythema and redness of skin are not indicative of a positive test result.
Store at 2°C to 8°C (36°F to 46°F); do not freeze. Protect from light. Opened vials should be discarded after 30 days.
Vaccines (Live): May diminish the diagnostic effect of Tuberculin Tests. Management: If a parenteral live vaccine has been recently administered, a scheduled PPD skin test should not be administered for at least 4-6 weeks following the administration of the vaccine. Exceptions: Cholera Vaccine. Consider therapy modification
False-positive reactions may occur with BCG vaccination or previous mycobacteria (non-TB) infection (previous BCG vaccination is not a contraindication to testing; however, an interferon gamma release assay is preferred [CDC 2010]). False-negative reactions may occur with any condition that impairs or attenuates cell-mediated immunity, including aging.
Frequency not defined:
Cardiovascular: Presyncope, syncope
Dermatologic: Erythematous rash, localized erythema, localized vesiculation, rash at injection site, skin rash, skin ulceration at injection site, urticaria at injection site
Hypersensitivity: Anaphylactoid reaction, anaphylaxis, angioedema, hypersensitivity reaction
Local: Injection site reactions, discomfort at injection site, hematoma at injection site, injection site scarring, local pruritus, localized edema, local tissue necrosis, pain at injection site
Respiratory: Dyspnea, stridor
• Viral infections: Skin testing may be deferred with major viral infections.
Concurrent drug therapy issues:
• Drug-drug interactions: Potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information.
• Pediatric: Infants <6 months of age may have an absent or delayed response.
• Administration: For intradermal administration only; do not administer IV, IM, or SubQ. Epinephrine (1 mg/mL) should be available to treat possible allergic reactions.
• Appropriate use: Patients with a previous severe reaction to TST (vesiculation, ulceration, necrosis) at the injection site should not receive tuberculin PPD again.
• Conditions decreasing response: Tuberculous or other bacterial infections, fungal infections, viral infection, live virus vaccination, malignancy, corticosteroids or immunosuppressive agents, chronic renal failure, severe protein depletion, afibrinogenemia, and other conditions that impair immune response may cause a decreased response to test.
Monitor for immediate hypersensitivity reactions for ~15 minutes following injection.
Pregnancy Risk Factor
Animal reproduction studies have not been conducted. Pregnancy is not a contraindication to testing (CDC 2005).
• Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)
• Have patient report immediately to prescriber severe dizziness; passing out; or injection site burning, discoloration, pain, skin breakdown, or edema (HCAHPS).
• Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.
Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for health care professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience, and judgment in diagnosing, treating, and advising patients.
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.