Skin Disorders Guide

The skin is an impressively large and heavy organ. It occupies well over a square meter of surface area and accounts for about 20% of total body weight. As the boundary between our body and a hostile world, it serves several functions. First, the skin acts as a barrier for fluid movement. Internal fluids are […]

Diagnostic Hallmarks

Distribution- face and shoulders
Pustules are intermingled with comedones and inflammatory papules

Clinical Presentation
A wide variety of lesions are found in acne, only a portion of which are pustules. Open comedones (blackheads) consist of a pigmented keratinous plug firmly lodged at the orifice of a sebaceous follicle. The reason for the black color is […]

Sunburn and photoinduced carcinogenesis occur as the result of irradiation in the ultraviolet B (UVB) (280- to 320-nm) range of light. Blockage of these wavelengths can be obtained through the use of sunscreens containing benzophenones, salicylates, p-aminobenzoic acid (PABA), esters of PABA, and cinnamates. Efficacy of these products is determined by measuring their sun protective […]

Melanocytes account for about 1 % of the cells of the epidermis. These dendritic, pigment-producing cells are derived from the neural crest and are first identified in the epidermis in 8-week-old embryos. In normal skin, they are found exclusively in the basal layer where they are interspersed among the basal keratinocytes. Each melanocyte, via its […]

Diagnostic Hallmarks

Distribution- hands, arms, legs, and scalp
Marked tendency for clustering
Lack of response to antibacterial therapy
Potassium hydroxide (KOH) preparation and fungal culture

Clinical Presentation
The dermatophyte fungi Microspar’um canis, Trichophyton rubrum, T mentagrophytes, and T. verrucosum may cause a perifollicular abscess that is clinically characterized by the presence of follicular pustules. All of these […]

Epidermis
The epidermis is the outermost layer of the skin and is the thinnest of the three layers. In practical terms, it 3 is no thicker than three or four pages of this book. The epidermis is responsible for the impervious nature of the skin. Fluid movement is restricted by the presence of a barrier zone […]

Diagnostic Hallmarks

Distribution: sun-exposed surfaces
Fade in winter, darken in summer
Size: smaller than 4 mm
Occurrence primarily in children

Clinical Presentation
Freckles are light-brown macules 1 to 3 mm in diameter. They occur as closely set, but not confluent, lesions on the lace, arms, and other sun-exposed skin. They occur primarily in fair-skinned people and are particularly […]