There are many conditions of or affecting the human
integumentary system—the
organ system that comprises the entire surface of the
body and includes
skin,
hair,
nails, and related
muscle and
glands.
History
In 1572,
Geronimo Mercuriali of
Forlì,
Italy, completed
De morbis cutaneis (translated "On the diseases of the skin"). It is considered the first scientific work dedicated to dermatology.
Epidemiology
In World War I, over two million days of service are estimated to have been lost by reason of skin diseases alone.
Approach to diagnoses
The physical examination of the skin and its appendages, as well as the mucous membranes, forms the cornerstone of an accurate diagnosis of cutaneous conditions. Most of these conditions present with cutaneous surface changes term "lesions," which have more or less distinct characteristics. Nevertheless, there are some commonly accepted terms used to describe the macroscopic morphology, configuration, and distribution of skin lesions, which are listed below.
Morphology
Primary lesions
bites on human skin showing characteristic welts.]]
Macule - A macule is a change in surface color, without elevation or depression and, therefore, nonpalpable, well or ill-defined, variously sized, but generally considered less than either 5 a lesion that is moist, circumscribed, and usually depressed.
Ulcer - An ulcer is a discontinuity of the skin exhibiting complete loss of the epidermis and often portions of the dermis and even subcutaneous fat.
Fissure - A fissure is a crack in the skin that is usually narrow but deep.
Wheal - A wheal is a rounded or flat-topped, pale red papule or plaque that is characteristically evanescent, disappearing within 24 to 48 hours.
Telangiectasia - A telangiectasia represents an enlargement of superficial blood vessels to the point of being visible.
Burrow - A burrow appears as a slightly elevated, grayish, tortuous line in the skin, and is caused by burrowing organisms.
Secondary lesions
Scale - dry or greasy laminated masses of keratin that represent thickened stratum corneum.
Crust - dried serum, pus, or blood usually mixed with epithelial and sometimes bacterial debris.
Lichenification - epidermal thickening characterized by visible and palpable thickening of the skin with accentuated skin markings.
Excoriation - a punctate or linear abrasion produced by mechanical means (often scratching), usually involving only the epidermis but not uncommonly reaching the papillary dermis.
Induration - dermal thickening causing the cutaneous surface to feel thicker and firmer.
Atrophy - refers to a loss of tissue, and can be epidermal, dermal, or subcutaneous. With epidermal atrophy, the skin appears thin, translucent, and wrinkled. Dermal or subcutaneous atrophy is represented by depression of the skin.
Configuration
"Configuration" refers to how lesions are locally grouped ("organized"), which contrasts with how they are distributed (see next section).
Agminate
Annular
Arciform or arcuate
Circinate
Digitate
Discoid
Figurate
Guttate
Herpetiform
Linear
Nummular
Mamillated
Reticular or reticulated
Serpiginous or gyrate
Stellate
Targetoid
Verrucous
Distribution
"Distribution" refers to how lesions are localized. They may be confined to a single area (a patch) or may exist in several places. Several distributions correlate an anatomical reference. Some correlate with the means by which a given area becomes effected. For example, contact dermatitis correlates with locations where allergen has elicited an allergic immune response. Varicella Zoster Virus is known to recur (after its initial presentation as Chicken Pox) as Shingles. Chicken Pox appears nearly everywhere on the body but Shingles tends to follow one or two dermatomes. (For example, the eruptions may appear along the bra line, on either or both sides of the patient.)
Generalized
Symmetric (one side mirrors the other with respect to the
Flexural (Front of the fingers)
Extensor (back of the fingers)
Intertriginous
Morbilliform
Palmoplantar (palm of the hand, bottom of the foot)
Periorificial
Periungual (under a finger or toe nail)
Alopecia (hair loss)
Blaschkoid
Photodistributed (places where sunlight reaches)
Zosteriform or dermatomal (associated with a particular nerve)
Other related terms:
Collarette
Comedo
Confluent
Eczema (a type of dermatitis)
Granuloma
Livedo
Purpura
Erythema (redness)
Horn (a cell type)
Poikiloderma
Combined (conjoint) terms (maculopapular, papuloerosive, papulopustular, papulovesicular, papulosquamous, tuberoulcerative, vesiculobullous, vesiculopustular) are used to describe eruptions that evolve from one type of lesion to the next so often appear as having traits of both, when transitioning .
Histopathology
Hyperkeratosis
Parakeratosis
Hypergranulosis
Acanthosis
Papillomatosis
Dyskeratosis
Acantholysis
Spongiosis
Hydropic swelling
Exocytosis
Vacuolization
Erosion
Ulceration
Lentiginous
See also
Dermatology
List of dermatologists
List of cutaneous conditions
References