Nearly one in ten people worldwide will develop eczema — a term that describes skin conditions characterized by irritated, inflamed, itchy patches. Eczema is also called dermatitis, and the two terms are often used interchangeably. In some people, eczema causes the skin to appear very red with a rash that seems to bubble up; in others it can appear scaly and dry with less discoloration. Eczema often appears after an itch has been scratched, and therefore is commonly referred to as “the itch that rashes.” In this animation you will learn about the way eczema occurs and what triggers it, different types of eczema, and how you can manage your eczema and possibly prevent future outbreaks.
The skin is composed of two layers: the epidermis and the dermis. The epidermis is the outer layer that acts as the body’s primary defense against the environment. The dermis, or innermost layer, is responsible for providing structure and support to the skin. Eczema is believed to arise when the body’s immune system is triggered into an abnormal, overactive, inflammatory response that involves both the epidermis and the dermis. Another theory suggests that in some cases a defective epidermis causes an individual to be particularly sensitive to substances that cause an inflammatory response. The inflammation that results from eczema irritates patches of skin, causing them to itch. Regions of elevated, fluid-filled bumps may also develop. With continued scratching these bumps may burst and exude pus and become crusty, or the skin may become dry and cracked. Although eczema is not commonly associated with life-threatening risks, if scratching causes any openings through the skin that penetrate into the dermis, the skin may become infected.
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Eczema occurs at any age and tends to arise in certain body areas more than others, depending on age. For example, in infants, eczema typically appears on the forehead, cheeks, forearms, legs, scalp, and neck. In contrast, children and adults most commonly experience patches of eczema on the face, neck, upper chest, elbow creases, wrists, hands, fingers, back of the knees, ankles, and feet. However, it is important to realize that eczema can occur on any part of the body at any age. Depending on the cause and type of eczema, it can spread over large areas of the body, or it may be confined to a specific region, as in cases where the eczema is triggered by contact with a particular substance. Eczema can also be associated with asthma and hayfever. Fillagrin gene mutation allows for the skin water barrier to be less efficient. This causes excessive skin dryness and soreness leading to skin inflammation (dermatitis). The immune system tends to respond in a different way to normal which compounds the situation. Allowing the skin to dry out, skin infection and (very rarely diet) can cause flares of eczema.
Although dermatologists do not fully understand the exact cause of all eczema, they have identified a variety of potential sources. Some people may have a genetic predisposition because eczema tends to be more common in people whose family members have allergies, asthma, or eczema. In others, eczema may result from a variety of factors known to trigger eczema flare-ups, which include the following categories and the examples shown on your screen.
The most common type of eczema is known as atopic eczema. Ten to twenty percent of infants in the United States are affected by atopic dermatitis. Although atopic dermatitis usually occurs before the age of five, it can appear for the first time, or reappear periodically, at any age. This type of dermatitis is believed to result from an interaction of genes, the environment, the way the epidermis renews itself in particular individuals, and an overactive immune system. Most affected individuals have a family history of allergies and one or two parents who have experienced eczema in the past.
Substances absorbed through the skin can lead to the development of allergic contact dermatitis. The skin often feels sore rather than itchy. Those with atopic dermatitis are more vulnerable to develop this problem. Common causes include Nickel, Chrome, Cobalt, Perfume, PPD and Colophony. Allergy ‘patch’ testing can confirm the causative chemical or substance.
Contact dermatitis occurs when a substance that causes an inflammatory response touches the skin. There are two primary forms of contact dermatitis known as irritant contact dermatitis and allergic contact dermatitis. Substances that irritate the skin, such as a chemical or a particular type of soap, cause irritant contact dermatitis. This form generally requires contact with a certain threshold amount of the irritating substance before symptoms develop. After contact with this threshold amount, the skin gradually starts to react and a rash typically develops in the exposed area. Allergic contact dermatitis arises after exposure to an allergen, such as poison ivy. Even small amounts of the allergen can trigger a response in susceptible individuals. Unlike irritant contact dermatitis, the body’s immune system may overreact in response to the allergen, which can cause inflammation to spread to areas of the body that didn’t actually contact the substance.
Skin can dry out and become sore if exposed to irritants. The skin then becomes more sensitive – even to minor irritants. People with atopic dermatitis are more vulnerable to this problem.
Although there is no real cure for eczema, symptoms can often be reduced or prevented by avoiding specific triggers, such as those shown on your screen. The most effective measure you can take to clear an eczema flare-up is to avoid the urge to scratch the affected area, as this may worsens outbreaks. To avoid further irritation, keep your fingernails short and smooth. Bathing in lukewarm water, using special cleansers, and applying moisturizers directly after bathing are also often effective in clearing symptoms. Other common treatments are shown on your screen. In the severe cases where other treatments have failed to work, medications that affect the body’s immune response may be recommended.
Contact dermatitis symptoms generally subside after removing the source. This process may take several weeks to clear, but can often be shortened to days with treatment. Oral medications prescribed for severe cases can be quite effective and have few side effects when taken for a short duration. About half of the atopic eczema cases in infants clear by a year and a half to two years of age, while others take longer or may never completely disappear. A person may continue to exhibit signs into adulthood, primarily as eczema on the hands. When treated, atopic eczema can be stubborn and is prone to recurring outbreaks. You may need to adjust how you use medications, switch to stronger medications, or even reduce your stress level by taking more time for relaxing activities. Fortunately, the therapies available today are often effective, and with proper treatment and prevention, most eczema can be controlled or even alleviated.
Often looking like a nettle rash or bee stings. Very itchy and flares are random and spontaneous. Sometimes aggravated by pressure on the skin, changes in temperature, sweating, water exposure, certain drugs or certain chemicals in the food. The problem is an immune defect (not an allergy) causing histamine release in the skin. An associated condition called angioedema can cause skin swelling especially of the lip or tongue.
Publications in Eczema, Urticaria and Allergy
Downs AMR, Sansom JE. Palmo-plantar dermatitis may be due to phenol formaldehyde resin contact dermatitis. Contact Dermatitis 1998; 39:147
Downs AMR, Lear JT, Sansom JE. Contact sensitivity in patients with oral symptoms. Contact Dermatitis 1998; 39:258-9
Downs AMR, Sharp LA, Sansom JE. Pentaerythritol esterified gum rosin as a sensitizor in Granuflex hydrocolloid dressing. Contact Dermatitis 1999; 41:162-3
Lotery H, Kirk S, Beck M, Bovera E, Crone M, Curly R, Downs AMR et al Dicapryyl maleate: an emerging cosmetic allergen. Contact Dermatitis 2007; 57:169-72.
Downs AMR, Fifield R, Sansom JE. IgG latex RAST is not a specific marker for type I hypersensitivity. Contact Dermatitis 1999; 41:223-4.
Downs AMR, Sansom JE. Colophony allergy - a review. Contact Dermatitis 1999; 41:305-10.
Downs AMR Topical immunomodulators in dermatology. Pulse July 2005
Bugowski P, Downs AMR Eczema, a treatment overview. www.doctors.org August 2012
Downs AMR, Kennedy CTC. A case of palmo-plantar pruritus responding to ondansetron. Arch Derm 1998; 134:925-6.
Downs AMR, Sansom JE, Simmons I. Let Rip! Fun Pot dermatitis. Contact Dermatitis 1998; 38:234.
Downs AMR, Lear JT, Kennedy CTC. A case of triamcinolone anaphylaxis. Arch Derm 1998; 134:1163-4
Downs AMR, Sansom JE. Occupational contact dermatitis to propolis. Contact Dermatitis 1998; 38:359-60.
Downs AMR, Lear JT, Wallington TB, Sansom JE. Contact sensitivity and systemic reaction to pseudoephedrine and lignocaine. Contact Dermatitis 1998; 39:33.
Downs AMR, Sansom JE. Airborne occupational contact dermatitis from epoxy resin in an immersion oil used in microscopy. Contact Dermatitis 1998; 39:267.
Downs AMR, Sansom JE. Severe contact allergy to footwear responding to handmade shoes. Contact Dermatitis 1999; 40:218.
Downs AMR, Lear JT, Dunnill MGS. Polymorphic light eruption confined to vitiligo. Clin Exp Derm 1999; 24:79-81.
Downs AMR, Kirkup M. The dangers of body painting. BMJ 1997; 315:1722.
Condon CA, Downs AMR, Archer CB. Terbinafine induced acute generalised exanthematous pustulosis. Br J Derm 1997; 138:709-10.
Downs AMR, Kennedy CTC. Somatrophin-induced acanthosis nigricans. Br J Derm 1999; 141:390-1.
Downs AMR, Kennedy CTC. The anti-pruritic effects of ondansetron. Arch Derm 1999; 135:599.
Kirkup ME, Downs AMR, Sansom JE. Does 5% doxepin cream affect patch test reactions? Br J Dermatol 2003; 148:847.
Downs AMR, Sansom JE. A retrospective assessment of colophony positive patients. 5th Congress of the European Society of Contact Dermatitis, Amsterdam, 2000.
Kirkup ME, Downs AMR, Unswoth JO, Sansom JE. Experience with tranexamic acid for non-hereditary angio-oedema and urticaria. BAD, Brighton 2003.
Bowling JCR, Scarbrick J, Warin AP, Downs AMR. Multicomponent hair dyes, hidden causes of allergic contact dermatitis. BAD, Brighton 2003
Bogucki P, Downs AMR, Interstitial granulomatous drug reaction (IGDR) triggered by infusion of eryrthomycin used as a sclerosing agent. EADV, Prague 2012
Bogucki P, Downs AMR. Erythema multiforme during treatment with IL-12 & IL-23 inhibitor. AAD, Miami 2013
Downs AMR, Charman CR, Lewis V. Integrated care approach to eczema: presentation of service data and potential quality measures from a community pilot clinic. EADV, Istanbul 2013
Ling GS, Downs AMR. Occupational airborne allergic contact dermatitis to usnic acid in an office-based dentist. AAD San Diego 2018.
Our consultants dermatologist have been managing eczema, urticarial and a wide variety of skin rashes as a consultant dermatologist since 2000.
We offer the management of all types of eczema/dermatitis, drug rashes & urticaria including patch tests for allergic contact dermatitis and blood tests for Type 1 allergies.