An abnormally hard spot or area on the skin.

imune complexes

the symptoms of pyomyositis are:
Early stage:
fever
localized inflammation
muscle pain
sepsis
tender induration of the effected muscle
late stages :
abscess formation
bacterimia and metastatic abscesses

A TB skin conversion is defined as an increase of 10 mm or greater of induration within a two year period, regardless of age.

The PPD skin test for tuberculosis is calculated in MM not percent. Induration of 2 or less than 2 mm, without blistering, is considered a negative skin test.