This illustration shows a deposit of dried serum on the surface of the skin.
This patient has remarkably thick mixtures of scale and crust on an inflammatory base with a predominantly acral distribution. Note also the thickened, pitted nails, the t hickening of the proximal nail folds, and the retraction of the cuticles. This constellation of findings, taken with an appropriate history, might allow the diagnosis of keratoderma blenorrhagicum, a nearly, but not quite diagnostic feature of Reiter's syndrome.