CLASS I. HYPEREMIAS AND INFLAMMATIONS
The above heading is selected for this class because the distinction between congestion and inflammation is one of clinical rather than pathological necessity, and no sharp line can be drawn between the congestive and inflammatory dermatoses, hence any separate classification is confusing. It is also thought unnecessary to specify a group of anemias, which are not diseases per se, but expressions of systemic disturbances shown in the skin following a reduction in the quantity of, or change in the quality of the blood.
ERYTHEMA
The term erythema, used alone, is an indefinite one, indicating a hyperemia or redness of the skin, which may be exudative or simply congestive. It is often difficult to draw a distinct line between these forms and a true dermatitis.