Dermatitis is defined as inflammation of the skin, and it encompasses many conditions. Also referred to as eczema, dermatitis is rarely debilitating, but it can be a constant source of frustration and insecurity. It is also one of the most common health conditions in the world, affecting more than 240 million people globally in 2015. Some versions of dermatitis are present at birth, or very soon after, making it a genetic condition as well as one than can be acquired.

What are the symptoms of dermatitis?

There are several forms of the condition, and each one presents with its own set of symptoms, but they all share some common characteristics. They include:

  • Redness of the skin (erythema)
  • Inflammation
  • Itchiness
  • Skin lesions (these may or may not scar or ooze)

The degree to which these symptoms are present depend on the exact form of dermatitis. For example, dermatitis that affects the genitals tends to be very itchy, while perioral dermatitis (dermatitis around the mouth) is less itchy and presents with red bumps.

When diagnosing dermatitis, the most important criteria is where the condition is located and whether the condition was acquired or has been present since birth. Once a healthcare provider establishes these criteria, they can take measures to alleviate symptoms the patient experiences.

What causes dermatitis?

The picture of dermatitis isn’t entirely clear, though in most cases, it is believed to be caused by a mix of environmental and genetic factors. The genetic side of the diagnostic equation is particularly interesting, as there are other medical conditions that often appear in concert with some forms of dermatitis. Recent genome studies have uncovered a few genetic variants linked with dermatitis, confirming that there is at least some association with a patient’s genetics and their eczema. Further, people with dermatitis are three times more likely to also suffer from celiac disease, making an even more compelling case for genetics.

Environmental factors are also implicated in how and when dermatitis presents. The most interesting of the environmental hypotheses is the clean environment hypothesis. In other words, there is evidence that shows children that are exposed to an unusually clean environment are more likely to develop dermatitis. Without bacteria and other immune system modulators present, the child’s system becomes hypersensitive and cannot properly measure its response to minor threats. One of the consequences, according to the hypothesis, is dermatitis.

How is dermatitis diagnosed?

Healthcare providers can normally diagnose the exact variety of dermatitis with little trouble using the patient’s history and a physical examination. If these factors cannot elucidate the problem, then a skin biopsy might be effective, especially when attempting to rule out food allergies.

There is some confusion regarding the terminology used to define a case of dermatitis. The biggest sticking point is the use of dermatitis versus eczema. Some physicians use the terms interchangeably, while some refer to atopic dermatitis as eczema, and acute forms of the condition as dermatitis. It’s helpful, then, to get a perfectly clear idea from the healthcare provider on what they mean exactly when referring to skin irritation as eczema or dermatitis.

That said, there are several forms of dermatitis that are firmly established and universally recognized by healthcare professionals. They include:

1. Atopic dermatitis – Atopic dermatitis is among the most common forms of the condition and some physicians refer to it as eczema to the exclusion of other versions of dermatitis.

When someone is said to be “atopic,” that means they have a tendency to be hyperallergic to allergens. In other words, the body does not formulate a proper response to a standard allergen load, so it’s usually impossible to determine what allergens are responsible.

Atopic dermatitis normally occurs during childhood, so it likely has a significant inheritable factor. It is most obvious on the scalp, but it can also manifest on the neck, behind the knees, inside the elbows and on the buttocks. For reasons not entirely understood, it often runs in families that also have a history of asthma.

Because atopic dermatitis presents like other forms of the condition, it is often misdiagnosed, so patients must be precise with their medical history.

2. Contact dermatitis – Contact dermatitis is split up into allergic dermatitis and irritant dermatitis. In both cases, the condition presents after the patient’s skin comes into contact with the offending material. Allergic dermatitis can be caused by a huge variety of allergens, including plants and animals.

Irritant dermatitis makes up 75 percent of contact dermatitis cases and is the result of contacting a detergent. A common detergent implicated in contact dermatitis is sodium lauryl sulfate, which is found in many shampoos and body washes.

Contact dermatitis is usually curable and preventable, as long as the patient can remove the problematic material from their environment.

3. Seborrheic dermatitis – Seborrheic dermatitis almost always involves the parts of the skin regularly exposed to the body’s natural oils. This includes the face, chest and scalp, and presents with red, itchy and scaly skin, so is often mistaken as dandruff.

Like most other forms of dermatitis, seborrheic dermatitis is believed to be the result of both genetic and environmental factors, and the former clearly has a major impact, as the condition is often seen soon after birth. When it is present in infants and involves the scalp primarily, it is referred to as cradle cap.

Though this form of dermatitis is not associated with poor hygiene, it can worsen when experiencing stress or in dry, cold climates. It also comes with some startling risk factors, as poor immune function, epilepsy, Down Syndrome and Parkinson’s disease all increase the likelihood of developing seborrheic dermatitis. Fortunately, it is typically treatable.

Less common forms of dermatitis include venous (also referred to as stasis), dyshidrosis, discoid, herpetiformis, neurodermatitis, autoeczematization and viral. These forms of dermatitis are usually the result of underlying health conditions, such as impaired circulation or infection, and can often be treated by resolving the primary problem.

Can a primary care physician treat dermatitis?

In the vast majority of cases, the answer is yes. Physicians are equipped to treat both children and adult patients with the condition, as more than half of the cases resolve during adolescence. However, treatment is focused on preventing symptoms, as dermatitis is not curable in many instances. Reducing symptom severity, though, can offer great relief to many.

The standard treatment for dermatitis is the use of antifungal or anti-inflammatory creams that reduce itching, swelling and redness. They are reliable in most cases, though a very few number of patients will not respond to them. The use of corticosteroids can help in particularly stubborn cases or during bad flare ups.

When possible, avoiding certain irritants, regular bathing and applying moisturizers to the skin can improve many instances of dermatitis without the need for medication. A healthcare provider can help patients determine which moisturizers to use and which irritants to avoid.

Dermatitis is one of the world’s most common health conditions, but that doesn’t make it any easier to live with. Fortunately, diagnosis and treatment are affordable, non-invasive and usually efficacious.