Mantoux skin test or PPD skin test is used to diagnose tuberculosis (TB). It is used to check the hypersensitivity of a individuals to tb.

Mantoux skin test procedure (ppd 2 step procedure)

There are various doses of tuberculin like 1 TU, 5 TU, 10 TU, 250 TU. But mostly 5 TU is used.

  1. Intradermally injecte 5TU ppd after cleaning the site with antiseptic.
  2. Read the induratiom after two to three days.
    • If induration is more than 10 mm after three days, than PPD skin test consider as positive.

Mantoux skin test results (Positive-Negative means)

PPD test result more then 10 mm mean

If ppd test induration is more than 10 mm after ppd intradermally injection then the test result is positive. The patient has had or has live tuberculosis in his body.

Purified protein derivative test: PPD skin test
Positive PPD test

Mantoux test negative

If there is no ppd induration after (72 HOURS) PPD intradermally injection then the test result is negative. It means the patient has not had primary tuberculosis.

False-positive TB test (PPD)

In the case of BCG vaccination, false-positive results can occur.

False-negative TB test (PPD)

There are the following cases that result in false PPD negative results..

  1. Recent Tuberculosis Infection.
  2. Anergy
  3. Very young age (less then six month)
  4. Live verus vaccine
  5. End renal Disease
  6. Poor nutration
  7. Measles
  8. Hodgkin’s disease
  9. Sarcoiddosis

False-positive TB test (PPD) means?

In the case of BCG vaccination, false-positive results can occur.

False-negative TB test (ppd test) mean?

It occurs in following conditions.
1. Recent Tuberculosis Infection.
2. Very young age (less then six month)
3. Live verus vaccine

How much dose is required for ppd tb test?

The recommend dose is 5 TU to 0.1 ml volume intradermal.

Mantoux test 6.5cm mean?

Between 5 to 10 mm induration means, boarderline.Test should be repeated after 8 weeks. But test can be positive in following conditions.
1. Person with fibrotic changes on chest with old healed tuberculosis.
2. HIV seropositive
3. Sever malnutritioned baby.

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