Mantoux test

The Mantoux test or tuberculin sensitivity test is a diagnostic test for tuberculosis. This test, also known as Piquet Test is endorsed by the American Thoracic Society and Centers for Disease Control and Prevention (CDC). The other diagnostic tests for tuberculosis are Tine test and Heaf test. Since the Mantoux test makes use of purified protein derivatives (PPD), it is also referred to as PPD test. This tuberculosis test does not indicate how long the infection has been festering or if it is in the active stage. This tuberculosis test is prescribed for persons who have abnormal chest x-rays or symptoms such as weight loss and persistent cough for many months. A Mantoux test is not recommended for those suffering from any skin conditions or allergy. Women who are pregnant or breastfeeding must not be subjected to the Mantoux test.

This PPD test involves injecting a dose of TB antigens into the top layer of skin on the forearm. The dose includes 10 Tuberculin units (0.2 ml) as this exposes the person to enough bacteria to mount an immune reaction in the skin. A little bump (wheal) is noticed under the skin. This area is then observed for any reaction in then next 48 - 72 hours. Reactions such as fever or swollen lymph nodes in the armpit must be brought to the notice of health professionals immediately. The results of this test must be interpreted carefully. A positive result indicates tuberculosis. There may be cases of false positives or false negative results. The significance of the Mantoux test on those vaccinated with BCG is still controversial.