Last Updated on January 20, 2021
Atopic dermatitis is a chronic relapsing inflammatory skin disease that results in red, inflamed, dry, and itchy skin. The disease has a genetic predisposition and usually begins in childhood. Itching and hyperirritability of the skin are its main features.
The term atopic is from the Greek meaning ‘out of place’ or ‘strange’. The term dermatitis means ‘inflammation of the skin’.
The terms atopic dermatitis and eczema are sometimes used interchangeably. Atopic dermatitis is one of the causes of eczema.
Eczema is a nonspecific term and refers to a skin condition that causes inflammation and irritation (dermatitis). Eczema can be of different types such as atopic, contact, irritant, and nummular eczema.
Read more about Eczema – Types, Causes, Risk Factors, and Treatment
Atopic dermatitis is a common condition worldwide. People who live in urban areas and in regions that have low humidity are at an increased risk. The incidence is continuously increasing worldwide in both industrialized countries and developing nations.
According to an estimate, about 20% of children and 3% of adults are affected by the disease. Males and females are affected equally.
Treatment involves regular rehydration of the skin with emollients or moisturizers. Topical steroids may be used to reduce inflammation and itching. Oral antihistamines also have a role in breaking the “itch-scratch” cycle. Oral antibiotics may be prescribed in case of secondary infection of the skin lesions.
Signs and Symptoms
Signs and symptoms of atopic dermatitis vary widely from person to person. Also, the severity varies greatly.
In more than 90% of the cases, the disease begins before the child is 5 years of age. Many children outgrow the disease as they get older. In some cases, the disease may persist into adolescence and adulthood. Rarely the disease begins in adulthood.
In some people, the disease flares periodically with a change of seasons or other environmental factors. This may be followed by periods when the skin lesions clear up completely called remissions.
Common symptoms include:
- Dry skin
- Itching: It can be very severe. It can be especially problematic during night time and may disrupt sleep.
- Rash: It is in the form of red to brownish patches and is usually itchy and scaly. Common sites are creases of the wrists, elbows, and knees, hands, feet, ankles, legs, neck, upper chest, and eyelids. In infants and young children, it can involve the scalp, face, cheeks, knees, and elbows.
- The skin rash may consist of small, raised bumps that ooze fluid. When scratched, they may show crusting.
- Scratching may result in the skin becoming raw, sensitive, and swollen.
- Intense itching may cause scratch marks.
- The presence of rash for a prolonged period of time can cause the involved skin to become thicker or lichenified.
- The dryness of the skin can worsen the itching and rash. An “itch-scratch cycle” usually occurs in which scratching the skin results in more irritation, and hence, more itching.
Read more about Itching or Pruritis: Causes, Diagnosis, and Treatment
Causes and Risk Factors
The exact cause of atopic dermatitis is not known.
It is thought to result from a combination of genetic and environmental factors.
Atopy is a special type of allergic hypersensitivity. Atopic dermatitis denotes hypersensitivity of the skin with an increased tendency for itching. The disease is associated with other atopic disorders such as hay fever (seasonal allergies), allergic rhinitis and asthma.
Read more about Allergic Rhinitis-Types, Clinical Features, Prevention, and Treatment
All these diseases have a hereditary component and are known to run in families.
Many children who outgrow atopic dermatitis as they grow older can go on to develop asthma or hay fever in adulthood. This is known as ‘atopic march’.
Patients of atopic dermatitis appear to have a misguided immune response.
They have either a reduced quantity of or a defective form of a protein called filaggrin in their skin. This protein is important in maintaining the integrity and hydration of normal skin. The deficiency of filaggrin results in the inability of the skin to protect from bacteria, irritants, or other environmental allergens.
Food allergies may be responsible in some cases, though they are not usually responsible for causing atopic dermatitis
Stress or other negative emotions are known to aggravate the condition.
Other factors that can trigger or aggravate atopic dermatitis, include seasonal allergies, exposure to harsh soaps, detergents or chemicals, house dust mite, pollens, animal dander, air pollution, dry and cold weather, etc. Exposure to these environmental factors can produce symptoms of atopic dermatitis in persons who have the atopic disease trait in their genes.
Is Atopic Dermatitis Contagious?
The disease isn’t contagious meaning that it can’t spread from one person to another through skin contact.
Some patients with atopic dermatitis get secondary skin infections with staphylococcus bacteria, other bacteria, herpes simplex virus, or fungal organisms. These infections may pass through close skin contact.
Complications of Atopic Dermatitis
- Skin infections: Repeated itching can break the skin resulting in open sores and cracks. These become vulnerable to infection from various bacteria and viruses.
- Chronic itchy, scaly skin: Scratching of the dry itchy skin further increases the itch. This propagates the scratch-itch cycle. Ultimately the affected skin may become discolored, thick, and leathery. This is called neurodermatitis or lichen simplex chronicus.
- Sleep problems: Severe itching at night can result in poor sleep quality.
- Asthma and hay fever: More than half of children with atopic dermatitis develop asthma and hay fever in adulthood. This is known as ‘atopic march’.
Diagnosis
The diagnosis is made on the basis of visually inspecting the skin. A personal or family history of allergies or asthma often supports the diagnosis.
Complete Blood Count
There may be an increase in eosinophil count.
Serum IgG
Increased levels usually confirm the diagnosis.
Thyroid function tests
Since hypothyroidism can result in dry and itchy skin, tests to detect any thyroid abnormality are used to rule out other causes of dry skin.
Skin swab test
It can help to identify Staphylococcal aureus superinfection.
Skin allergy tests
The various types of skin tests include scratch, intradermal, and patch tests. The skin is exposed to a particular allergen and the response of the skin to that allergen is noted. The results of the test need to be interpreted with caution as there may be a significant number of false-positive or false-negative results.
Read more about Allergy Skin Tests – Indications, Procedure, and Interpretation
Blood allergy tests
A sample of blood is withdrawn and examined for the presence of antibodies that fight specific allergens. This test is able to detect IgE antibodies against common allergens.
Skin biopsy
A small piece of skin is sent to the lab to be examined under the microscope by a pathologist. The changes seen can help to diagnose the disease. This test is not required for the diagnosis and is not routinely performed. Its importance lies in ruling out cancerous conditions of the skin (such as cutaneous T-cell lymphoma) which may present with similar features.
Diagnostic criteria
According to the American Academy of Dermatology (AAD) 2014 Guidelines, the following features should be considered for the diagnosis:
Essential features that must be present:
- Itching
- Eczema
- Typical features and areas of involvement (facial/neck/extensor involvement in children, flexural involvement in any age group)
- Chronic or relapsing history
Important features that support the diagnosis:
- Early age of onset
- Atopy
- Personal and/or family history
- Elevated IgE levels
- Dryness of the skin
Self-care Tips and Home Remedies
- Use skin creams, petroleum jelly, or emollients frequently to moisturize your skin and prevent dryness. It is best to apply these immediately after a bath when the skin is still damp so that the moisture gets locked within the skin.
- Avoid frequent baths.
- Use lukewarm water for bathing in cold weather. Do not use hot water as it irritates the skin.
- Oatmeal can be added to water for bathing.
- Very dilute bleach baths (in a proportion of one quarter to one-half cup of bleach mixed with 150 liters of water bath) once or twice weekly can improve the rash and prevent skin infections.
- Use a mild soap for bathing. The soap used should not rob the skin of its natural moisture or irritate your skin.
- Cleansing agents or soaps used should have a low pH so as to maintain the acidic pH of the skin. This helps to preserve the skin barrier function and reduces skin irritation.
- Use sunscreens when out in the sun to prevent sunburns and skin damage.
- Avoid fabrics that irritate the skin, such as wool and synthetics. Use cotton clothing and bedsheets. Even in winters, do not let the woolen clothes come in direct contact with the skin. Always wear a layer of cotton clothing underneath the woolens.
- Always wear light and loose-fitting clothes. Avoid wearing tight or restrictive garments.
- Warm and dry air tends to make the skin dry. So avoid excess use of heaters or air conditioners. You can also use a humidifier to prevent the air from becoming dry.
- Try to avoid common allergens like pollen, pet dander, dust mites, and mold. At home, dust and vacuum regularly. Wash bedding weekly in hot water. Avoid using heavy drapes and carpeting at home or workplace.
- Avoid hot or spicy foods or alcoholic beverages.
- Resist the temptation to scratch your skin. Try pressing on the skin rather than scratching.
- Keep your fingernails short. This may prevent damage to the skin if you can’t resist the urge to scratch
- To relieve itching, place a cool cloth or some ice over the skin that itches.
- Cooling lotions like calamine, menthol, and camphor provide a soothing effect to the irritable skin. They stimulate the nerve fibers which transmit the sensation of cold, and hence mask the itchy sensation.
- Avoid stress and anxiety. Taking care of your emotional health by practicing meditation and other behavioral modification techniques can help to prevent flare-ups.
Treatment
There is no definite cure for atopic dermatitis. Treatment aims at relieving the symptoms and regular moisturizing of the skin.
If regular moisturizing and other home remedies don’t provide relief, prescription medicines or other treatments may be recommended.
Topical corticosteroid ointments
They are applied after moisturizing the skin. They are quite effective. Commonly used steroids are hydrocortisone, triamcinolone, or betamethasone valerate. However, they shouldn’t be used for prolonged periods as they may cause thinning of the skin. As soon as the lesions disappear, steroid ointment should be discontinued and can be resumed when a new rash appears.
Anti-allergic medicines
Oral H-1 receptor blockers or antihistaminics are effective as they tend to break the scratch-itch cycle. Commonly used drugs are hydroxyzine, diphenhydramine, chlorpheniramine, cetirizine, and loratadine. Due to their sedative effect, they are particularly useful in patients who face problems in sleeping due to intense itching. However, their effects can persist into the daytime and can impair cognitive function, such as alertness learning, and memory. Non-sedative alternatives like fexofenadine may be used if sedation is not acceptable to the patient.
Antibiotics
Antibiotic cream is applied if the skin shows a bacterial infection. In some cases, oral antibiotics may be prescribed for a short duration to treat an infection.
Oral steroids
Oral drugs such as prednisone may be rarely prescribed in very severe cases to control inflammation. Although effective, they can’t be used for a long time because of serious side effects.
Read more about Side Effects of Corticosteroid Therapy
Immunomodulators
Tacrolimus and pimecrolimus are non-steroidal topical ointments. They work as immune modulators by inhibiting a substance called calcineurin which has a role in inflammation. They are especially useful in children when applied on the faces as they don’t cause skin thinning.
In 2006, a black box warning was issued in the US about the potential risk for cancer with these drugs. Although these claims are still being investigated, these drugs should only be used in persons more than 2 years of age and only when other treatments have failed. Moreover, they are quite expensive.
Anti-IL-4Ra therapy (dupilumab)
A new monoclonal antibody called dupilumab (Dupixent) has been recently approved by the US Food and Drug Administration (FDA) for the treatment of severe atopic dermatitis in adults who are unresponsive to other treatments. It inhibits interleukin (IL)–4 and IL-13 signaling by blocking the shared IL-4Ra. It is given by injection twice a month and is quite expensive.
Crisaborole (eucrisa)
It is another recently approved drug for the treatment of children and adults with mild to moderate atopic dermatitis. It is in the form of topical ointment and works by acting as a phosphodiesterase-4 (PDE-4) inhibitor.
Wet-wrap therapy
It is used in patients with severe eczema having widespread skin lesions. Topical medications (steroids or other medications as described above) are applied to the affected areas of the skin. Then, a wet dressing (wet gauze or clothing) is placed over it. On top of it, a dry wrap material, such as elastic bandage is placed.
This is an effective treatment usually carried out in hospital settings under nursing expertise.
Light therapy
This treatment is reserved for people who either don’t respond to other treatments or who rapidly flare again after adequate treatment.
Ultraviolet light – UV-A, UV-B, a combination of both, psoralen plus UV-A (PUVA), or UV-B1 (narrow-band UV-B) therapy may be used.
Though effective, this therapy has side effects, such as premature aging of the skin and an increased risk of skin cancer. Hence it should not be used in children or infants.
Long–term Outlook
Home remedies and lifestyle changes along with intermittent use of medications can help to relieve dry skin, provide relief from itch and rashes, and prevent future flare-ups.
Thus atopic dermatitis or eczema is usually manageable. With adequate care and treatment, most of the patients can enjoy a high quality of life and participate in all activities.
References
- Eichenfield LF, Tom WL, Chamlin SL, Feldman SR, Hanifin JM, Simpson EL, et al. Guidelines of care for the management of atopic dermatitis: section 1. Diagnosis and assessment of atopic dermatitis. J Am Acad Dermatol. 2014 Feb. 70(2):338-51.
- Carlsten C, Dimich-Ward H, Ferguson A, Watson W, Rousseau R, Dybuncio A, et al. Atopic dermatitis in a high-risk cohort: natural history, associated allergic outcomes, and risk factors. Ann Allergy Asthma Immunol. 2013 Jan. 110(1):24-8.
- Spergel JM. From atopic dermatitis to asthma: the atopic march. Ann Allergy Asthma Immunol. 2010 Aug. 105(2):99-106.
- Van Velsen SG, Haeck IM, Bruijnzeel-Koomen CA. Severe atopic dermatitis treated with everolimus. J Dermatolog Treat. 2009. 20(6):365-7.
- Huang JT, Abrams M, Tlougan B, Rademaker A, Paller AS. Treatment of Staphylococcus aureus colonization in atopic dermatitis decreases disease severity. Pediatrics. 2009 May. 123(5):e808-14.
- Heller M, Shin HT, Orlow SJ, Schaffer JV. Mycophenolate mofetil for severe childhood atopic dermatitis: experience in 14 patients. Br J Dermatol. 2007 Jul. 157(1):127-32.