FIGURE 17.6 A Positive Tuberculin Skin Test Injection of tuberculin protein into the skin of a person sensitized to Mycobacterium tuberculosis causes a firm red raised area (induration) to form within...

Explain why a tuberculin skin test on an AIDS (acquired immunodeficiency
syndrome) patient with tuberculosis may show a negative result.

Extracted text: FIGURE 17.6 A Positive Tuberculin Skin Test Injection of tuberculin protein into the skin of a person sensitized to Mycobacterium tuberculosis causes a firm red raised area (induration) to form within 48 to 72 hours. A reaction greater than 10 mm in diameter is considered positive.