Hi, need to submit a 750 words essay on the topic Skin allergy.Urticaria or hives is an itchy rash, due to hypersensitive reaction by the skin (Linscott, Emedicine). The condition may be acute or chro

Hi, need to submit a 750 words essay on the topic Skin allergy.

Urticaria or hives is an itchy rash, due to hypersensitive reaction by the skin (Linscott, Emedicine). The condition may be acute or chronic and there are several variants to this condition. Itching can occur without any rash and may be due to some disease related to that part of the skin. Even some medications can cause itching.

As far as atopic dermatitis is concerned, the cause is actually unknown. However, several researchers have attributed genetic and environmental mechanisms to the development of atopic dermatitis. Factors which contribute to the development of atopic dermatitis are infection, poor hygiene, extremes of climate, food antigens and aeroallergens (Kraffchik, Emedicine). Several chemicals sensitize the skin and cause allergic contact dermatitis. Some of the important chemicals are poison ivy, Nickel, rubber gloves, p-phenylenediamine, dyes, formaldehyde, wash and wear chemicals and preservatives (Hogan, Emedicine). In urticaria, the cause is unknown most of the times. However, ingections, foods, stress, drugs, exposure to certain temperatures and climates and exposure to latex can trigger the development of the condition (Linscott Emedicine).

In atopic dermatitis, the pathophysiology is poorly understood. However, it has been thought that sensitization of IgE and epithelial barrier disturbance secondary to some kind of immune dysfunction is the cause for the allergic rashes. Another important defect attributed to this condition is defective epithelial cells contributing to defective barrier mechanism (Kraffchik, Emedicine). The main immune disturbance is imbalance in the T-lymphocytes with TH2 cells dominating the system and causing release of cytokines like granulocyte macrophage stimulating factor and interleukins 4,5, 12 and 13. All these amount to an increase in IgE levels and fall in interferon gamma levels. In those with chronic