The eruption is usually associated with a strongly positive tuberculin reaction.

The tuberculin reaction was first described by Robert Koch in 1890.

Tuberculin reaction or Type 1 diabetes belong to this category of autoimmunity.

Developed the Moro test (percutaneous tuberculin reaction)

After recovering, Rhoads authored a paper on the tuberculin reaction with Fred W. Stewart.

In terms of mechanism of action and appearance, the reaction is similar to the tuberculin reaction of a positive Mantoux test for tuberculosis.

In cases of anergy, a lack of reaction by the body's defence mechanisms when it comes into contact with foreign substances, the tuberculin reaction will occur weakly, thus compromising the value of Mantoux testing.

Someone with a positive tuberculin reaction is not given BCG, because the risk of severe local inflammation and scarring is high, not because of the common misconception that tuberculin reactors "are already immune" and therefore do not need BCG.

The pathophysiology of the Tuberculin reaction is explained thus: M. tuberculosis are engulfed by macrophages after being identified as foreign, but due to a self-preserving mechanism peculiar to TB it is able to block the fusion of the phagosome within which it is existing with the lysosome which would destroy it.