Mantoux Test

I have just taken a medical screening which is requested by JPA, and I will be collecting the report on Tuesday. The tests include physical examination such as height, weight,blood pressure, pulse etc and lots more like chest X-ray and others which I don’t remember.

The most troublesome test of all is the Mantoux Test. For you guys wondering wth is a mantoux test, below are extracts from wikipedia. Hope you find it useful. =D

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The Mantoux test (also known as the Mantoux screening test, Tuberculin Sensitivity Test, Pirquet test, or PPD test for Purified Protein Derivative) is a diagnostic tool for tuberculosis. It is one of the two major tuberculin skin tests used in the world, largely replacing multiple-puncture tests such as the Tine test.

Tuberculin is a glycerol extract of the tubercle bacillus. Purified protein derivative (PPD) tuberculin is a precipitate of non-species-specific molecules obtained from filtrates of sterilized, concentrated cultures. It was first described by Robert Koch in 1890. The test is named after Charles Mantoux, a French physician who developed on the work of Koch and Clemens von Pirquet to create his test in 1907.

Procedure

A standard dose of 5 Tuberculin units (0.1 mL) is injected intradermally (between the layers of dermis) and read 48 to 72 hours later. A person who has been exposed to the bacteria is expected to mount an immune response in the skin containing the bacterial proteins.

The injection was “disgusting-ly” painful man. The pain of the initial ant bite before extracting a test tube-full of blood is totally incomparable with this. First, I felt the needle piercing through the skin, then the needle “travels” between the skin layers. When the tuberculin is being injected, I felt as though something was hitting the bones. After that, a swelling just like that caused by a mosquito bite appeared.

The reaction is read by measuring the diameter of induration (palpable raised hardened area) across the forearm (perpendicular to the long axis) in millimeters. If there is no induration, the result should be recorded as "0 mm". Erythema (redness) should not be measured.

I’ll have the reading taken on Tuesday.

If a person has had a history of a positive tuberculin skin test, another skin test is not needed, but if negative another test may be needed.

Classification of tuberculin reaction

The results of this test must be interpreted carefully. The person's medical risk factors determine at which increment (5 mm, 10 mm, or 15 mm) of induration the result is considered positive. A positive result indicates TB exposure.

• 5 mm or more is positive in
  • HIV-positive person
  • Recent contacts of TB case
  • Persons with nodular or fibrotic changes on chest x-ray consistent with old healed TB
  • Patients with organ transplants and other immunosuppressed patients
• 
  
• 10 mm or more is positive in
  • Recent arrivals (less than 5 years) from high-prevalence countries
  • Injection drug users
  • Residents and employees of high-risk congregate settings (e.g., prisons, nursing homes, hospitals, homeless shelters, etc.)
  • Mycobacteriology lab personnel
  • Persons with clinical conditions that place them at high risk (e.g., diabetes, prolonged corticosteroid therapy, leukemia, end-stage renal disease, chronic malabsorption syndromes, low body weight, etc)
  • Children less than 4 years of age, or children and adolescents exposed to adults in high-risk categories
• 
  
• 15 mm or more is positive in
  • Persons with no known risk factors for TB
  • (Note: Targeted skin testing programs should only be conducted among high-risk groups)

A tuberculin test conversion is defined as an increase of 10 mm or more within a 2-year period, regardless of age.

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I’ll receive my test report on next Tuesday. Hopefully everything’s fine just like last year (this is the second medical check-up I did, exactly the same as that I took before entering KTT last year).

Tata. =D