Skin

Excerpt

Skin, our vital interface with the environment, is the largest organ of the body. It effectively prevents or neutralizes most physical, chemical, and biologic assaults; extends our senses (touch, feel, temperature, pain); and, with eccrine sweating, provides a thermoregulatory control that is unique among animals. The skin also serves as an immunologic organ, and its role in the regulation of lymphocytes appears to be yet another important, protective function. The fabric of skin, its epidermis, and supporting dermis contains most of the structural elements found in the deeper body organs. It should be examined, then, with the expectation that changes in its appearance are signs of external damage or a reflection of hidden, systemic disease. The various conditions are diagnosed by their primary, or characteristic, lesions, which must be precisely defined in order to be appropriately classified (Table 105.1).

The nondermatologist should be advised that the peculiar argot of the specialty, which at first seems daunting, represents an additional aid to diagnosis. Most of the odd-sounding Greek and Latin names turn out to be either literal or metaphoric descriptions of the disorders. There is much learning, and even fun, discovering what pityriasis rosea, lupus erythematosus, comedo, and mycosis fungoides really mean. A standard medical dictionary, or special dermatologic lexicon, will make the conditions studied more truly memorable!