We combined eczema and atopic dermatitis in this article for simplicity although they are considered separate diseases. Eczema (or atopic dermatitis) is the most common chronic skin disease and affects about 10% of adults and 30% of children.1 Most cases of eczema occur during childhood within the first few months of life but it can appear at any age. The condition may be associated with asthma and allergies particularly food allergies which result in hives most of the time.2 Asthma and seasonal allergies may develop later in life at approximately at 5-10 years of age. Some children grow out of eczema, allergies, and asthma, but they can sometimes persist into adulthood. Thankfully, not every child with eczema develops these additional conditions but patients that suffer from eczema should know they are at risk.
Over the last 10-15 years, the approach to allergies and prevention of eczema has shifted significantly. The previous recommendations were to avoid any possible food that may cause allergies, but now newer scientific studies do not support this advice. The opposite is true; foods that usually cause allergies such as peanuts are slowly introduced and eating them in small quantities may be protective for eczema, food allergies, asthma, and seasonal allergies.2 Similar to psoriasis, eczema is not simply a minor or cosmetic problem. Many patients affected with eczema experience higher rates of ADHD, stress, and may be in emotional distress due to the appearance of their inflamed skin.3
Eczema, like psoriasis and many other skin diseases, is a disease which is related to both genetic and environmental factors. There is an essential building block of the skin which may be missing in people with eczema, is hereditary, and can affect almost half of those who suffer from eczema. This component missing from the skin is a protein called filaggrin. There are dozens of other genetic causes of eczema and are beyond the scope of this article.4 Thankfully, all of them are extremely rare. Patients with eczema, due to problems with the protein needed for normal function of the skin, have problems with keeping their skin intact and it easily becomes red, flaky, scaly, or itchy. This predisposes them to superficial skin infections with bacteria called “staph” (Staphylococcus aureus) and their body tends to overreact to the normal bacteria on the skin.5 The skin of patients with eczema also over-react and activate the immune system to the components of normal skin similar to an autoimmune disease.6
Eczema sufferers usually experience severe itching from an early age, raised, red, scaly, flaky patches across the body, and periods where the skin is completely clear one week to severe flare ups the next without any explanation. In young children, the face is usually the most severely affected especially the cheeks. As children grow older, eczema tends to improve on the face and spreads to the folds including the inside of the arms and backs of the calf. In adults, eczema usually involves the eyelids, face, hands, and legs but can be present anywhere on the skin. The skin spots sometimes weep a clear fluid due to microscopic swelling of the skin just like poison ivy. Sometimes eczema can leave a footprint where it was previously and cleared up called post inflammatory changes. This is not a scar but simply an area of the skin that either gained or lost pigmentation temporarily due to prior inflammation. Patients with eczema may have rough, dry, scaly patches of skin that is non-inflamed but appears chronically dry especially during the wintertime. Also, patients with eczema are predisposed to bacterial or viral infections of the skin. Scalp eczema may have clinical overlap with a dry scalp or even dandruff given the features.
The most important treatment for any child or adult who suffers from eczema is to restore the natural barrier and function of the skin with a moisturizer. Because the barrier is predisposed to flaking, redness, itching, and scaling, daily prevention is necessary. In fact, applying a daily moisturizer from birth may reduce the risk of developing childhood eczema by 50%.7 It is important to apply a moisturizer right after lukewarm water bathing (avoiding hot water) to ensure adequate absorption of the cream. It is also important to use a humidifier during the winter months. In families with a high rate of eczema, breast-feeding or using a specific cow’s milk formula has been shown to decrease the risk of eczema.8 In pregnant women, taking probiotics or eating yogurt can also reduce the risk of passing eczema along to the baby.9
Many patients with eczema also have a high-risk of skin allergies so any irritating substances should be avoided. Gentle soaps should be used and abrasive clothing such as wool which may irritate the skin should be avoided. Additionally, occupations with a high risk of allergy exposure should be avoided including those who work as professional cleaners, hairdressers, food preparers, or those that immerse their hands in water for more than two hours per shift.10,11 Reduction of the amount of skin bacteria with so called “swimming pool baths” because they contain a dilute bleach solution which safely reduces bacteria (usually combining ½ a cup of bleach in a full bathtub) has also been shown to improve eczema.12 More recently, the application of coconut oil has been shown to improve atopic dermatitis or eczema after 8 weeks of use.13
Many prescription treatments may be effective for eczema including topical steroids, prescription light treatments, or even oral medications that control the overactive immune system such as methotrexate. Anti-inflammatory treatments that are not topical steroids have also been developed such as tacrolimus ointment and are useful for the face and body folds.
Additional treatments are needed if it becomes difficult or unrealistic to apply ointments or if topical steroids are no longer working. Frequent use of oral steroids, although they work quite well, are strongly discouraged as they increase the risk of diabetes, cataracts, thinning of the bones, and obesity. Also, once the course of steroids is complete, the skin problem can recur. More recently, targeted immune-modulating injectable treatments have been developed which fight eczema by blocking the signals which start the rash in the first place called dupilumab.