Skin Disorders Guide

Diagnostic Hallmarks

Distribution: random but some predilection for the back
History of a preceding noninflammatory cyst or nodule
Solid fragments of white keratin on incision and drainage

Clinical Presentation
Asymptomatic, skin-colored epidermoid cysts occasionally become red and tender. When this occurs, differentiation from a furuncle may become difficult. The history of a preceding noninflammatory nodule, the absence [...]

Diagnostic Hallmarks

Distribution: axillae and groin
Nonresponsiveness to antibiotic therapy
Chronic course with recurrence in the same sites

Clinical Presentation
The individual lesions of hidradenitis suppurativa arise as firm, lender, dome-shaped papules and nodules 1 to 3 cm in size. The larger lesions often become fluctuant and drain spontaneously. Pustule formation at the summit of the inflamed nodule is sometimes [...]

Diagnostic Hallmarks

Distribution: no characteristic pattern
Sudden onset
Pain and tenderness
Response to therapy

Clinical Presentation
Furuncles are painful, dome-shaped or slope-shouldered, bright red nodules 1.5 to 3 cm in diameter. Usually, only a single furuncle is present; multiple lesions, if closely grouped, may coalesce to form a carbuncle. The classic signs of inflammation (rubor, dolor, color, and tumor) are all [...]

Psoriasis is usually associated with plaque formation. Some people (mostly children and young adults), however, explosively develop 50 to 100 small, nonconfluent papules over the trunk and proximal extremities. This phenomenon, known as guttate psoriasis, is particularly likely to be precipitated by a preceding streptococcal infection or by an episode of severe emotional stress. The [...]

Diagnostic Hallmarks

Distribution- sun-exposed surfaces of the face, hands, and
shoulders
No seasonal venation in pigment density
Size: 5 to 20 mm
Occurrence in adults

Clinical Presentation
Lentigines (singular- lentigo) are brown macules 5 to 20 mm in diameter. The brown hues vary in intensity from tan to brown-black. They occur singularly or as multiple, closely set (but not cont1uent) lesions [...]

Apocrine Sweat Glands
Apocrine sweat glands develop, like sebaceous glands, from follicular epithelial cells. For this reason their ducts open into the follicular lumina. They are phylogenetic remnants of the sexually important scent glands of animals but seem to have no direct usefulness in humans today. Apocrine glands are found primarily in the axillae, perineum, [...]

A lesion is a general term for a single, small area of skin disease. Lesions may be solitary or multiple. Terms used to describe these lesions include macules, patches, papules, plaques, nodules, vesicles, pustules, bullae, erosions, and ulcers. Some authorities divide these lesions into primary and secondary types.
Rash
The term rash is collectively used to [...]

Diagnosis Hallmarks

Distribution - trunk and extremities, special predilection for the wrists, penis, and mouth
Violaceous color
Shiny, flat-topped papules
Koebner phenomenon
Wickham’s striae

Clinical Presentation
The primary lesion of lichen planus is a violaceous, flat-topped papule 2 to 4 mm in diameter. Scale, because it is of lichen type, is often overlooked, the shiny, mirror-like surface of the papules is [...]

Groups 9 and 10 are characterized by the presence of red scaling lesions. The scaling, which differentiates these two groups from groups 7 and 8, may or may not be readily apparent. Three types of scale must be sought . Psoriatic-type scale (large white or gray flakes) can be easily seen, but pityriasis-type scale is [...]

Diagnostic Hallmarks

Distribution: vertical, central third of the face
Pustules and papules against a background of erythema and telangiectasia

Clinical Presentation
Rosacea is characterized by macular erythema, overlaid with telangiectasia, on the nose and cheeks. Often, the glabella and chin are involved such that the eruption forms a vertical band down the central third of the face. In the [...]