Skin Disorders Guide

Diagnostic Hallmarks

Distribution: trunk, but palm and sole involvement IS characteristic when present
Target lesions
Papules and plaques are similar but less transient than those in urticaria

Clinical Presentation
Erythema multiforme is characterized by the presence of flat-topped, sharply marginated papules 1 to 2 cm in diameter. The color is generally duskier than the hright red of urticarial lesions. Typically, […]

Diagnostic Hallmarks

Distribution - sun-exposed portions of the face and ears
Occurrence against a background of sun-damaged skin
Rolled border, translucent appearance

Clinical Presentation
Basal cell carcinomas appear as smooth-smfaced, skin-colored, somewhat translucent (”pearly”) papules. Lesions 4-6 mm in size are flat-topped with rounded or rolled shoulders. Those 6-8 mm in diameter usually show a central dimpling. Larger lesions […]

Diagnostic Hallmarks

Distribution: face and legs (flat warts); genitalia and perirectal area (genital warts)
Tendency for clustering or confluent growth when more than one is present

Clinical Presentation
Genital warts (condylomata acuminata, venereal warts) and flat warts lack visible or palpable surface keratin, and both demonstrate a marked tendency for clustering and a lesser tendency for confluent growth.
Genital warts […]

Diagnostic Hallmarks

Sun-exposed surfaces of the face, ears, bald scalp, hands, and arms
Lesions occur on visibly sun-damaged skin
Lesions occur primarily in fair-skinned people who tan poorly

Clinical Presentation
Clinically, actinc keratoses consist of little more than bits of scale adherent to sun-damaged skin, there is little in the way of underlying substance on palpation. Small lesions […]

Erylherna nodosurn commonly presents as a tender erythematous plaque simulating an area of cellulitis. A location on the “interior lower leg, stability in size, a chronic course, and a lack of rapid response to antibiotic therapy should suggest the possibility of erythema nodosum rather than cellulitis.Patients with severe acne frequently develop tender inflamed cystic lesions. […]

The “attributes of lesions” represent the adjectives that are used to modify those nouns. In both verbal and written description it desirable first to pick an appropriate noun from the list of lesions and then to add as many modifiers as necessary to accurately complete the characterization of the lesion in question.
Margination
Margination is the […]

Diagnostic Hallmarks

Distribution - face, upper trunk, and proximal arms
Central feeder vessel with arborizing telangiectatic vessels
Association with liver disease and hormones

Clinical Presentation
The central feeding arteriole is a macule (or very small papule) 1 to 2 mm in diameter. Multiple small telangiectatic vessels (”legs”) radiate outward from the central vessel. Pressure on the central […]

Several of the nonvesicular viral exanthems including rubella and rubeola are characterized by the presence of red macules 1 to 2 cm in diameter. The occurrence of such lesions in the setting of characteristic clinical symptoms and signs allows for correct diagnosis. Roseola (exanthem subitum), recently found to be caused by human herpesvirus 6 is […]

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 […]