An Overview of Dermatitis

Dermatitis is irritation or inflammation of the skin. There are many types of dermatitis. Some, such as diaper rash, are characterized by red skin on a specific area of the body. Others involve blisters or breakouts that resemble acne. Dandruff is considered a mild form of dermatitis that affects the scalp. Because most types of dermatitis have a distinctive appearance, they often can be diagnosed based on a physical exam, although other testing, such as patch testing to determine if a specific allergen is to blame for dermatitis, sometimes is necessary. Treatment for dermatitis depends on the type and includes measures to relieve dry skin, itching, and other symptoms.

Types

Strictly speaking, almost any rash could be considered dermatitis. However, dermatologists generally use this term for several specific skin conditions.

• Allergic contact dermatitis is a delayed reaction to touching something you're allergic to (such as nickel) or certain ingredients in personal care products.
• Irritant contact dermatitis is a non-allergic reaction to having direct contact with an item or substance that irritates the skin. Detergents, solvents, and other chemicals are common causes of irritant contact dermatitis.
• Atopic dermatitis is itchy, red, and/or flaky skin that is most common in early life but can affect a person at any age. This rash often occurs in people who have a variety of allergies, although the rash can occur in susceptible people even without exposure to any particular allergen. A specific allergen is not always involved
• Stasis dermatitis results from poor circulation in the ankles and lower legs, causing the skin in these areas to become dry, itchy, scaly, and discolored. Severe statis dermatitis can result in complications such as cracks in the skin oozing sores, or an infection called cellulitis.
• Diaper dermatitis, more commonly known as diaper rash, is a common condition of infancy characterized by a red rash on a baby's bottom and nearby skin caused by extended exposure to a wet and/or soiled diaper.
• Dyshidrotic dermatitis (pompholyx) affects the palms, sides of fingers, soles of feet, and the area between the toes. It starts as a rash made up of small, itchy blisters that eventually become scaly spots. This rash can lead to cracked skin and be painful. Outbreaks tend to recur.
• Nummular dermatitis is also known as nummular eczema or discoid eczema. This condition appears as itchy, red, scaly, coin-shaped patches anywhere on the body. Potential causes include an allergic reaction such as a burn or insect bite.
• Seborrheic dermatitis is characterized by yellow, greasy scales on the scalp and hair-bearing areas of the head, neck, and upper chest. Dandruff is a mild form of seborrheic dermatitis. In babies, this condition is known as infantile seborrheic dermatitis or cradle cap.
• Autosensitization dermatitis is characterized by itchy, water-filled blisters that develop in response to an intense inflammatory process somewhere else on the body, such as a fungal infection. This response is known as an ID reaction.
• Perioral dermatitis is a rash caused by a variety of triggers, including irritants and/or allergens. It affects the skin around the mouth and can sometimes be mistaken for an acne breakout. Many times, the cause is never identified.

Symptoms

Changes in the appearance of the skin are the most obvious symptom of dermatitis. Many types cause a dry, red rash. Others are characterized by more distinct changes such as scaling or flaking, blisters, distinct patches of affected skin, or acne-like breakouts.

Itching is common among most types of dermatitis and can be quite intense and uncomfortable. Scratching can lead to a condition called lichen simplex chronicus, in which frequent scratching causes skin to become thick, leathery, and discolored.

Diagnosis

Determining the specific cause of dermatitis often can be done based on a physical exam and medical history taken by a doctor. A general practitioner can diagnose obvious cases, while others may need to be assessed by a dermatologist or an allergist.

Testing sometimes is necessary. For example, to diagnose the cause of dermatitis caused by an allergic reaction, a patch test may be required. This involves placing small amounts of suspected allergens on an unaffected area of skin to see if any bring on an allergic reaction.

A KOH test, in which samples of skin or nails are placed in a solution of potassium hydroxide and examined under a microscope, can identify an underlying fungal infection associated with dermatitis.

Finally, because some types of dermatitis resemble other skin conditions, a practitioner may need to assess for other conditions such as psoriasis or rosacea.

Treatment

Treatment for dermatitis typically focuses on relieving symptoms. Often an over-the-counter hydrocortisone cream can effectively reduce dry skin and itching. For severe dermatitis, a prescription topical steroid may be necessary. An oral antihistamine can ease intense itching.

Some types of dermatitis require specific treatment. For example, a dandruff shampoo may help clear up seborrheic dermatitis. Diaper rash often can be alleviated with more frequent diaper changes and a generous layer of diaper cream to create a barrier between a baby's skin and moisture.

It's also important to avoid allergens or contact with known irritants to prevent reoccurrences of dermatitis.

A Word From VeryWell

Dermatitis is a common skin condition. Though it can be uncomfortable, painful, or embarrassing at times to have an itchy rash on your body, once correctly diagnosed most types of dermatitis can be effectively treated and prevented. This is why it's important to see a doctor about any rash or other skin change you develop. The sooner you start treatment, the sooner your symptoms may subside.