What Are the Precautions to Take After a Tuberculosis Skin Test?

Update Date: 2024-05-16 Source: Network

If you suspect that you may have contracted tuberculosis, a tuberculin skin test can be performed. After undergoing the tuberculin skin test, which is also known as the tuberculin test, there are several important considerations to keep in mind. For instance, it is advisable to avoid spicy foods in your daily diet to prevent skin irritation. Additionally, the tested area should not be bumped or irritated, and the use of cosmetics or cleansers is not recommended.

The tuberculin purified protein derivative (PPD) test refers to the immune response generated by the body after initial infection with Mycobacterium tuberculosis. When the body is infected with M. tuberculosis again, a localized intense reaction known as the Koch phenomenon may occur. Administering tuberculin intradermally to patients with tuberculosis can cause a local allergic reaction.

Previously, the tuberculin commonly used in China was a metabolite of M. tuberculosis, derived from heat-inactivated, human or bovine strains cultured in vitro and filtered to remove dead bacteria. The main active ingredient is tuberculin protein, along with other substances like glycerol, which can lead to nonspecific reactions and false positive results. As a result, its use has been largely discontinued, and the PPD skin test is now more commonly employed.

PPD is a purified protein derivative of tuberculin, containing four proteins (A, B, C, D) and two types of polysaccharides (I, II). The PPD-s, a standard tuberculin preparation recognized internationally, is widely used in China.

Common Scenarios:

(1) No infection with Mycobacterium tuberculosis.

(2) Elderly individuals in poor health, patients with malignancies, or severe tuberculosis.

(3) Patients receiving immunosuppressive agents or corticosteroids.

(4) Patients with acute infectious diseases such as measles or scarlet fever.

(5) Expired PPD reagent.

Precautions:

1. For patients suspected of having active tuberculous lesions, the PPD skin test should be started with a low concentration of 1TU.

2. The PPD skin test diluent should be prepared before use, and the storage time in the refrigerator should not exceed 1 week. Shake the solution well before injection, and discard it if precipitates or discoloration are observed.

3. If there is skin breakage at the injection site, a corticosteroid ointment can be applied.