When a tuberculin skin test is positive, the hard center and erythema surrounding the induration are a result of which of these? (Select all that apply.)
A)Histamine
B)T lymphocytes
C)Immune complexes
D)Products of complement
E)Macrophages

Question

Quizplus · Accepted Answer

The reaction site is infiltrated with T lymphocytes and macrophages, resulting in a clear hard center (induration) and a reddish surrounding area (erythema).

When a Tuberculin Skin Test Is Positive, the Hard Center