Dermatitis: overview, causes, symptoms, diagnosis and management

Dermatitis is the term used for the skin condition in which it gets inflamed. Inflammation means the skin may swell, redden, itch or show rashes. Since, the inflammation can have any offending cause therefore dermatitis can be caused by infections, allergies or irritating substances. There are various forms of dermatitis depending upon the cause but atopic and contact dermatitis are the two most common forms. The term eczema is frequently used interchangeably with dermatitis but when used alone it usually refers to allergic dermatitis.

Types and causes

Atopic dermatitis is a lifelong skin condition that is inherited in most of the individuals. It can occur at any point of time in life but usually first appears during infancy. More than half of these infants grow out of atopic dermatitis by school age but flareups still occurs throughout the life. It may be associated with food allergies. Irritating substances like harsh soaps, chemicals and irritants can worsen atopic dermatitis.

Contact dermatitis: it occurs when skin comes in contact with a substance. If the substance is known to cause allergies it is known as allergic contact dermatitis or if it causes injury to the skin it is called as irritant contact dermatitis and it is the most common type of contact dermatitis. Common sources which can cause allergic contact dermatitis are cosmetics, dyes, adhesives, rubber derivatives and metals. Those substances that damages the oily protective layer of the skin can lead to irritant contact dermatitis like detergents, soaps, harsh disinfectants and chemicals.

Seborrheic dermatitis: It consists of greasy, yellowish or reddish scaling on the scalp, face or genital.  It can occur in both infants and adults. In milder forms it can cause dandruff in adults.

There are other forms of dermatitis too like stasis dermatitis, juvenile plantar dermatosis that are less common.

Signs and symptoms

Reddening, itching, scaling, dryness etc. may be the signs in any form of dermatitis but different forms of dermatitis have specific forms of signs and symptoms. Dry skin with severe itching and responsiveness to the environmental stimulus are important hallmarks of atopic dermatitis but their presentation varies with the age as

In infancy:

• Red, itchy and dry patch of skin
• Rashes on the cheeks which can ooze if scratched.
• Scaly or crusted lesion on arms, legs, trunk or scalp

In adolescence

• Rashes on the creases of hands or in the folding region of arms, legs, groin and neck
• Brownish-grey skin rash which may show thickening

Symptoms of contact dermatitis are different in allergic cases when compared to irritants. In allergic contact dermatitis the skin may show

• Reddening leading to blisters
• These blisters can ooze and these blisters are not infective and doesn’t spread to the others part of the body.
• Itching which can be intense

The symptoms of irritant contact dermatitis are related to the exposure and becomes more severe if left untreated

• Itching and mild swelling
• Dryness or cracking skin
• Blisters which can ooze
• Unhealed blisters can lead to ulceration.

Diagnosis

You must visit a healthcare professional if you suspect any of the symptoms of dermatitis or skin rash. The diagnosis of atopic dermatitis is purely clinical. The doctor will use your medical history, perform some tests to find out the type and cause of dermatitis

Medical history: The doctor will ask you about the symptom’s duration, any history of similar illness in the family, your work exposure, any use of cosmetics or dye or substance on the skin. It will help your doctor to narrow down the possible causes.

Physical examination: your doctor will look for the morphology and distribution of skin lesions across different parts of the body which may or may not be related to any substance exposure. Rashes of atopic dermatitis are known to occur more on the body creases.

Patch test: it is used for the diagnosis of allergic contact dermatitis. In this test, doctor put small samples of chemicals on an area of skin to see if the rash develops.

Management

Atopic dermatitis is a chronic condition which is not curable. It has a periodic course of flaring or worsening followed by improvement. Some people experience no symptoms at all for several years. It is possible to control symptoms with the help of medications and self-care measures like

Eliminating triggers: patients need to identify factors that increase the symptoms and try to eliminate these factors. Some of the common triggers are

• Dry or cold environments
• Rapid temperature changes
• Anxiety or emotional stress

Skin should be kept hydrated with the help of emollients.

Medications can be used to manage skin irritation and itching like

• immunosuppressants like topical or oral steroids can be used to control inflammation.
• over the counter antihistamines can help relive itching like diphenhydramine or hydroxyzine. Wet dressings can also be applied over the affected area.

The management of contact dermatitis includes

• Identification of the offending allergen or irritating substance and avoidance
• treatment of skin inflammation with the help of immunosuppressants
• use of skin moisturizer like emollients to restore the protective action of skin.

Prognosis

The prognosis of acutely occurring irritant contact dermatitis is better than people suffering from long term contact dermatitis. The recovery of barrier function of the skin occurs approximately within four weeks after irritant exposure.

References

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