Mantoux Test in Chennai

What is a Mantoux Test?

The Mantoux test, or tuberculin skin test (TST), involves injecting a small amount of purified protein derivative (PPD) from TB bacteria under the skin of the forearm. It measures delayed hypersensitivity to determine if a person has been infected with Mycobacterium tuberculosis, which causes TB. It identifies latent TB infection but does not confirm active disease.

Why is the Mantoux Test Performed?

• Doctors recommend the test to:
• Screen for latent TB in high-risk groups
• Assess individuals exposed to someone with active TB
• Evaluate healthcare workers, immigrants from high-prevalence areas, or those with weakened immunity
• Investigate symptoms suggestive of TB or before starting immunosuppressive treatments
• Support diagnosis in children, close contacts, or people in congregate settings

How is the Mantoux Test Performed?

The inner forearm is cleaned with alcohol

A tiny amount (0.1 ml, usually 5 TU PPD) is injected intradermally, creating a small pale bump (wheal) 6–10 mm wide

The site is not bandaged

Return in 48–72 hours for reading: a trained professional measures the raised, hardened area (induration) in millimetres across the forearm (not redness)

Avoid scratching, rubbing, or applying creams to the site.

Preparation for the Mantoux Test

• Inform your doctor about recent vaccinations (live vaccines within the past month), previous TB tests or treatment, viral illnesses, immunosuppressive drugs, or HIV status
• No fasting is required
• Wear loose sleeves for easy access to the forearm

Risks and Side Effects

The test is generally safe. Possible effects include:

• Mild itching, redness, or swelling at the site
• Rare fever or blistering
• Very uncommon allergic reactions
• These usually resolve without treatment.

Mantoux Test Normal Range and Interpretation of Results

• Results depend on induration size (in mm) and individual risk factors. Measure only the firm raised area, not surrounding redness.
• Mantoux test normal range (negative in low-risk individuals): 0–4 mm induration.
• Interpretation guidelines (commonly used, may vary by guidelines and risk):
• Mantoux test positive means prior exposure to TB bacteria (latent infection likely), requiring further evaluation (e.g., chest X-ray, sputum tests) to rule out active disease.

Mantoux test negative means no significant immune response to tuberculin, suggesting no TB infection (or very recent infection without time to react in severely immunocompromised).

BCG vaccination history does not usually alter interpretation; positive results in vaccinated individuals are assessed by risk.

Always consult your doctor for personalised interpretation.

Why Choose Unittas Hospital?

Unittas Multispeciality Hospital is a NABH-accredited centre with branches in Tambaram and Kelambakkam, conveniently located for patients across Chennai and the OMR corridor. Our state-of-the-art in-house laboratory features advanced analysers for precise diagnostic testing, supported by experienced pathologists and specialists who deliver expert interpretation and personalised guidance.

We ensure quick turnaround with same-day or next-day results in most cases, comfortable phlebotomy areas, private spaces for result discussions, and seamless connections to specialist consultations — all in a single facility. With a strong emphasis on compassionate, patient-focused care, hygienic premises, and flexible timings, Unittas is a trusted choice for reliable diagnostics in Chennai.