Eczema

Eczema or dermatitis is a skin inflammatory condition that causes a scaling process associated with itching. Dermatitis is one of the most common occupational diseases, resulting from exposure to substances in the workplace. It is, therefore, a contact dermatitis: the skin reacts abnormally when it comes into contact with a certain agent, which may be of chemical, biological, or synthetic origin.

Occupational dermatitis is categorized into two types:

• Allergic contact dermatitis: An inflammatory response of the skin to an external agent where an allergic immune process is involved, meaning an immune reaction is triggered by a substance (allergen) to which the person is sensitive.
• Irritative contact dermatitis: The inflammatory response of the skin does not involve an allergic component but occurs due to direct contact with an irritant, i.e., a physical or chemical agent that can cause cellular damage in any person if applied in a sufficient concentration for a minimum amount of time. This is the most common type of contact dermatitis.

Although it may reduce the quality of life of patients, occupational dermatitis generally has a good prognosis.

Symptoms

The symptoms of eczema manifest in the area of skin that has been in direct contact with the irritant agent. The areas most commonly affected are the hands and wrists, but eczema on the face, eyelids, arms, and legs is also frequent. The most common symptoms of eczema are:

• Red spots or patches
• Inflammation
• Scaling
• Fissures or cracks
• Intense itching, in the case of allergic eczema
• Pain, burning, or tenderness, in the case of irritative eczema
• Dry skin
• Blisters, which may ooze and form scabs
• Occasionally, skin thickening with marked grooves and wrinkles (lichenification)

Causes

Allergic contact dermatitis occurs following an immune reaction known as type IV hypersensitivity or delayed hypersensitivity, mediated by T lymphocytes, a type of immune system cell. After a period of sensitization following initial exposure to the substance, a subsequent contact causes the previously sensitized and activated T lymphocytes to react to the specific antigens present in the allergen, releasing cytokines, which cause a local inflammatory phenomenon that leads to cellular damage and triggers the rest of the associated symptoms. Allergic eczema appears between 12 and 48 hours after contact with the allergenic agent.

The most common allergens in the occupational environment include:

• Metals: nickel, chromium, cobalt, or mercury
• Resins, epoxy compounds, formaldehydes, and acrylics
• Rubber additives and rubber accelerators
• Plants and insecticides
• Dyes
• Fragrances and cosmetics
• Cutting oils
• Animal or plant proteins

Irritative contact dermatitis is due to an unspecific inflammatory response, without prior sensitization, caused when the irritant agent directly damages the epidermal cells (keratinocytes). This damage triggers an immune reaction that activates the action of T lymphocytes against the antigen and the release of cytokines responsible for the inflammatory response. Irritative eczema typically has a progressive manifestation after continuous exposure for days or weeks. However, if the irritant is very strong, the reaction can appear immediately.

Common irritants in the workplace include:

• Soaps, bleaches, and detergents
• Acids, alkalis, acrylics, and solvents
• Fiberglass
• Peroxides
• Fertilizers and disinfectants
• Petroleum distillates
• Abrasives
• Adhesives
• Fibers
• Humidity and extreme temperatures

Risk Factors

The primary risk factor for occupational eczema is working in an environment with regular exposure to allergenic and irritant agents. Professions most commonly affected include:

• Construction workers
• Dentists and dental technicians
• Farmers, livestock breeders, florists, and gardeners
• Food handlers, chefs, and bakers
• Hairdressers and beauticians
• Painters and restorers
• Medical and veterinary staff
• Metalworkers, machinists, and mechanics
• Printers and photographers
• Textile workers
• Cleaning staff
• Workers in the paper, glass, and plastic industries
• Electronics and electrical sector workers
• Chemists

Additionally, other conditions that increase the likelihood of developing contact dermatitis include:

• A history of atopic dermatitis
• Concentration and skin penetration ability of the agent
• Duration of exposure
• Presence of wounds or lesions on the skin

Complications

Constant scratching and rubbing of eczema leads to scaling and oozing, which favors the entry and spread of microorganisms such as fungi or bacteria, potentially causing an infection. If the infection is not treated and spreads to the tissues beneath the skin or regional lymph nodes, it can lead to serious damage to the body.

Prevention

To prevent occupational eczema, it is essential to take protective measures against allergenic and irritant agents:

• Use of protective equipment such as gloves, goggles, face masks, or special clothing
• Application of barrier creams or gels
• Immediate skin washing after each contact

Which doctor treats eczema?

Occupational eczema is evaluated and treated by specialists in dermatology and allergology from the occupational medicine unit.