Sudolorrhoea

This is characterized by the appearance of one or more slightly reddened, barely elevated, and sharply limited patches, more or less thickly covered with a few greasy scales. These appear occasionally on the scalp; more frequently, however, on the contiguous skin along the hairy border, and still more frequently on the chest in men - rarely in this region in women.

The affection is essentially sub-acute in its behavior, and chronic in its duration. Vigorous friction will remove the scales and leave a surface not wholly unlike that of a dry eczema which has been submitted to the same treatment, and occasionally will excite a slight oozing of oleaginous matter, quite different, however, from the clear but plastic exudation of eczema. If a little liquor potassae be rubbed on the spot, we will have under the finger a thin, non-adhesive emulsion, and not the sticky layer which follows a like application to a patch of eczema.



Besides the regions mentioned, the affection may appear on the back, and, according to Unna, on the lower extremities. The patches may vary in number and in shape, being round, oval, semilunar, or irregular, as if made up of several circular patches which had united; in fact, it may assume the varieties of form that are familiar to us in connection with psoriasis, for which disease it is not infrequently taken.

Sudolorrhoea, when left unchecked by treatment, often persists with varied activity, for an indefinite period, even for years.

Nothing definite is known as to the cause of the affection. It is possibly due to a micro-organism, but this has not as yet been positively shown to be the case.