Epidermal atrophy

In laboratory animals, TCDD administered in suitable doses has produced a wide variety of toxic effects, including a wasting syndrome (severe weight loss accompanied by reduction of muscle mass and adipose tissue), thymic atrophy, epidermal changes, hepatotoxicity, immunotoxicity, effects on reproduction and development, teratogenicity, and carcinogenicity. The effects observed in workers involved in the manufacture of 2,4,5-T (and therefore presumably exposed to TCDD) consisted of contact dermatitis and chloracne. In severely TCDD-intoxicated patients, discrete chloracne may be the only manifestation. 

There are hundreds of topical steroid preparations that are available for the treatment of skin diseases. In addition to their aforementioned antiinflammatory effects, topical steroids also exert their effects by vasoconstriction of the capillaries in the superficial dermis and by reduction of cellular mitosis and cell proliferation especially in the basal cell layer of the skin. In addition to the aforementioned systemic side effects, topical steroids can have adverse local effects. Chronic treatment with topical corticosteroids may increase the risk of bacterial and fungal infections. A combination steroid and antibacterial agent can be used to combat this problem. Additional local side effects that can be caused by extended use of topical steroids are epidermal atrophy, acne, glaucoma and cataracts (thus the weakest concentrations should be used in and around the eyes), pigmentation problems, hypertrichosis, allergic contact dermatitis, perioral dermatitis, and granuloma gluteale infantum (251). 

Fig. 15.2. a Biopsy of a 50-year-old Caucasian woman showing epidermal atrophy and collagen degeneration, b Biopsy of a 50-year-old African American woman showing minimal to no evidence of photodamage... 

Ah receptor (AHR) A protein coded for by a gene of the Ah locus. The initial location of the Ah receptor is believed to be in the cytosol and, after binding to a ligand such as TCDD, is transported to the nucleus. Binding of aromatic hydrocarbons to the Ah receptor of mice is a prerequisite for the induction of many xenobiotic metabolizing enzymes, as well as for two responses to TCDD epidermal hyperplasia and thymic atrophy. Ah-responsive mice have a high-affinity receptor, whereas the Ah-nonresponsive mice have a low-affinity receptor. 

Stretch marks can only be treated definitively by applying aggressive treatments that can improve the epidermal and dermal atrophy that accompanies them. 

Stretch marks are the result of severe dermal and epidermal atrophy, lack of appendages and an extreme paucity... 

Photoaging solar keratoses, pigmentary lesions, epidermal atrophy and solar elastosis are indications for resorcinol if their histological origins are not too deep. 

In addition to all the structural changes that can follow exposure to ionizing radiation, there is a possibility that the pilosebaceous units might atrophy. This would delay epidermal regeneration and promote the formation of nasty... 

Corticosteroids 2-i times/day Local tissue atrophy, degeneration, and striae epidermal thinning acneiform eruptions baderial or fungal skin infections glucocorticoid systemic effects... 

After 14 hours, the epidermal lesions are significant in certain places the epidermal cells are extremely swollen (pseudo-acanthosis ), elsewhere we see an atrophy of the epidermis and next to it, either a pseudo-acanthosis, or an acanthosis. Intra-epidermal vesicles are frequently seen (Fig. 20). 

The use of topical corticosteroids, used in the successful treatment of ACD, has been questioned as a treatment for irritant dermatitis (van der Valk and Maibach 1989). They may be effective in chronic, hyperkeratotic irritant dermatitis, but their prolonged use may lead to epidermal atrophy and, consequently, increased irritant sensitivity. Other therapeutic options in irritant dermatitis include topical tars and phototherapy (ultraviolet B or psoralen plus ultraviolet A). In difficult cases of chronic, irritant hand dermatitis, radiation may be indicated (Goldschmidt and Pan-izzon 1991). Bacterial superinfection may be a complication of contact dermatitis it is treated with topical or systemic antibiotics. Potential irritants, such as irritant cleansing products, must be identified and (whenever possible) eliminated, not only in the workplace but in the home (Frosch 1989). 

Delayed healing may occur following peehng and hypertrophic or keloid scarring can occur in such areas [278], Telangiectasia, changes in pore size, and epidermal atrophy can develop after chemical peeling [278]. 

Histopathological examination of skin biopsy samples has revealed nonspecific findings including epidermal atrophy, keratosis, and basal membrane hyperpigmentation. Nonspecific fibrosis and melanophages... 

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