Eczema is a common skin condition that is often poorly understood. In most cases it is mild, but a number of complications can occur that may require prompt intervention by a doctor or nurse.
Eczema is known in medical terms as atopic dermatitis. It is caused by a defect in the integrity of the skin's barrier. As such, the skin becomes more susceptible to triggers that cause it to become inflamed. Triggers include soaps, washing powders and conditioners, infections, chemicals and foods. Most patients, however, do not need to be referred for allergy testing. National guidelines on eczema discourage the use of internet allergy testing.
The word 'atopic' implies a genetic predisposition to conditions such as eczema as well as hayfever and asthma, while 'dermatitis' suggests inflammation of the skin. The suffix 'itis' describes an inflammatory process, in this case, of the skin. Atopic illnesses often run in families and the word 'atopic' distinguishes this condition from other types of dermatitis.
Eczema tends to occur in young children, but fortunately, for many it improves with age. In some people, however, it doesn't regress and may indeed deteriorate during their teens and in adulthood. In addition, other atopic conditions may become manifest over time.
SYMPTOMS
In children under the age of 18 months, eczema tends to affect the cheeks and what is described as the 'extensor' surfaces, such as over the knees and elbows. From then on, the inflammation tends to be concentrated on the so-called 'flexor' surfaces, which are the bends of the elbows and behind the knees. The extensor surfaces are more likely to be affected in people with dark skin.
Inflammatory spells of eczema, known as flares, tend to occur intermittently over time. During a flare, the affected skin becomes itchy, red, swollen, sore and dry, and the affected person may become irritable. Scratching breaches the skin surface, introduces bacteria to the area and promotes further inflammation. Over time, affected areas become thickened - this is known as lichenification. Bacterial infection may cause the eczematous skin to become very red and exude pus. Without treatment, the infection may spread rapidly.
Other, more serious but rare complications of bacterial infections include abscess formation, pneumonia and blood poisoning. Bacteria commonly implicated in skin infections include staphylococcus aureus. The cold sore virus, known as herpes simplex, may also infect areas of eczema known as eczema herpeticum. In this case herpetic blisters and ulcers cause the eczematous skin to become very painful.
MANAGEMENT AND TREATMENT
The symptoms of eczema may be highly distressing for a child. They commonly cause sleep disturbance which, in turn, may have a profound effect on the family as a whole. In addition, eczema in older children and adults may have a significant psychological impact.
The management of eczema involves educating the parents and carers of affected children, trying to keep the inflammation under control and treating the complications of eczema. The mainstay of keeping the inflammation at bay is avoidance of triggers and the use of moisturisers known an emmolients. In babies in whom food allergy is suspected, alternatives to cow's milk may be offered as a treatment for eczema.
Emmolients should be applied liberally to the whole body a few times each day, irrespective of whether the skin is quiescent or inflamed. They should be used as a substitute for soaps, and oils should also be added to the bath water.
Steroid creams are used for flares of eczema and should be commenced within 48 hours of symptoms. The strength of the steroid and the length of treatment is determined by the doctor and tailored to the severity of the flare. Antibiotics or antiviral drugs are prescribed for bacterial infections or eczema herpeticum respectively. Severe or complicated infections may require hospitalisation.
Short courses of anti-histamines may be used under the guidance of a doctor for children who suffer a significant itch.
Additional specialist treatments for the prevention and treatment of flares include drugs called calcineurin inhibitors, bandages and wet-wrap therapy, and light therapy. National guidelines have concluded that there is not enough evidence to recommend the use of complementary therapies such as homeopathy - indeed, liver damage has been associated with some herbal therapies.
Eczema is usually a mild condition, but it can have quite devastating complications, such as infection. Using emmolients appropriately and avoiding triggers may be enough to prevent flares in children. Flares should be treated early with steroids and antibiotics where appropriate. When in doubt or when symptoms are severe, medical advice should always be sought.
