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TST (tuberculin skin test)
The tuberculin skin test (TST) is an intradermal injection of purified protein derivative (PPD) that elicits a delayed-type hypersensitivity reaction to detect prior or current tuberculosis infection.
The tuberculin skin test (TST) is an intradermal injection of purified protein derivative (PPD) that elicits a delayed-type hypersensitivity reaction to detect prior or current tuberculosis infection. Used for Detection of tuberculosis infection (latent or active), Screening for TB exposure in healthcare workers and high-risk populations, Evaluation of suspected tuberculosis disease.
At a glance
| Generic name | TST (tuberculin skin test) |
|---|---|
| Sponsor | Johns Hopkins University |
| Drug class | Diagnostic immunological test |
| Modality | Small molecule |
| Therapeutic area | Infectious Disease / Immunology |
| Phase | FDA-approved |
Mechanism of action
When PPD is injected intradermally, it stimulates T-cell mediated immune responses in individuals previously exposed to Mycobacterium tuberculosis. The resulting induration (hardening) at the injection site, measured 48-72 hours later, indicates cell-mediated immunity to TB antigens. A positive reaction suggests TB infection (latent or active), while a negative reaction generally rules out TB infection in immunocompetent individuals.
Approved indications
- Detection of tuberculosis infection (latent or active)
- Screening for TB exposure in healthcare workers and high-risk populations
- Evaluation of suspected tuberculosis disease
Common side effects
- Local induration and erythema at injection site
- Vesiculation or necrosis (in strongly positive reactions)
- Systemic hypersensitivity reactions (rare)
Key clinical trials
- Training Protocol on the Natural History of Tuberculosis
- Bedaquiline Roll-out Evidence in Contacts and People Living With HIV to Prevent TB (PHASE2, PHASE3)
- PREVAIL VIIIa: Evaluation of Latent Tuberculosis Infection Screening Methods in People Living With Retroviral Infection in Liberia
- The DECIDE-TB Trial; Validation of Treatment Decision Algorithms for Childhood Tuberculosis (NA)
- Online Transdiagnostic Group CBT for Postpartum Depression and Anxiety (NA)
- INflammatory MediatorS in the PathophysIology of Diabetic REtinopathy Study (PHASE1)
- Intralipid® 20% for Reversal of Local Anesthetics (PHASE4)
- The Safety and Efficacy of Intravitreal Topotecan for the Treatment of Proliferative Vitreoretinopathy (PHASE1)
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
Competitive intelligence
For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:
- TST (tuberculin skin test) CI brief — competitive landscape report
- TST (tuberculin skin test) updates RSS · CI watch RSS
- Johns Hopkins University portfolio CI