PustuleA pustule is an elevation of the epidermis, small oi large, by a purulent exudation. The principal diseases in which pustules are found, and their chief features are: - Acne; Small, scattered pustules, resulting from the suppression of papules, chiefly met with on the face, back, and chest.
- Ecthyma; Scattered pustules, of medium size.
- Eczema; Closely aggregated pustules, of small size.
- Dermatitis multiformis; Pustules associated with other lesions.
- Furuncles; A pustule seated at the apex of an inflamed, painful, and slightly elevated spot.
- Scabies; Isolated pustules, especially frequent about the hands and wrists.
- Syphilis; Pustules succeeding papules, or occurring without them.
- Variola; Umbilicated pustules which follow vesicles, and which were preceded by papules, discrete or confluent.
The common feature of these three lesions - vesicle, bulla, pustule - is a fluid exudation - serous, sero-fibrinous, or purulent - which lifts up a greater or less extent of horny epidermis, producing an elevation on the skin, and the lesion consists of an effused fluid, kept in bounds by a limiting membrane.
A vesicle, bulla, or pustule having formed may further progress in one of several ways. After a few days the effusion may be reabsorbed without rupture of the epidermis, and leave nothing but a loosely attached scale, which soon exfoliates. On the other hand, the epidermis may rupture in a day or two, the effusion be poured out, and the whole dry up to a small crust, which in a few days more is wholly detached; or, still again, a vesicle or pustule may rupture promptly, but from the denuded surface a serous or purulent fluid may continue to exude for several days or even weeks.
|