(Last Updated on : 13/03/2014)
Many types of dermatitis or eczema are seen developing on the skin. Almost all types of dermatitis have in common an allergic reaction to specific allergens. The disease can broadly be divided into two main types like acute and chronic. The acute dermatitis is related to a rapidly evolving red rash that may be blistered and swollen and the chronic dermatitis is referred to a longstanding irritable area. This area is often darker than the surrounding skin; thickened (lichenified) and much scratched. Another two major types of dermatitis are allergic dermatitis and contact (irritant) dermatitis. These two types are most commonly seen in workplaces and they together comprise a major portion of all reported occupation-related diseases in India. The other common types of dermatitis include the atopic dermatitis, Contact dermatitis, Seborrheic dermatitis, nummular dermatitis, Neuro dermatitis, Stasis dermatitis, Dyshidrotic dermatitis, etc.
The atopic dermatitis is considered as one of the most common types of dermatitis.
This is characterised by itchy, inflamed skin and is believed to be caused by an abnormal function of the body's immune system.Depending upon exposures to triggers or causative factors, the atopic dermatitis tends to come and go, on a regular basis. This type of dermatitis starts in infancy, and is sometimes termed as infantile eczema. It tends to run in families, and people who develop the condition often have a family history of allergic conditions like asthma or hay fever.
Contact dermatitis is another type of dermatitis, which is actually a localised reaction including redness, itching, and burning. The contact dermatitis may develop when the skin has come into contact with an allergen (an allergy-causing substance to which an individual is sensitized) or with a general irritant like an acid, a cleaning agent, or other chemicals. Apart from these, reactions to laundry detergents, nickel (present in jewelry), cosmetics, fabrics, clothing, and perfume, may also cause contact dermatitis. The main cause behind the development of this type of dermatitis can be difficult to determine, as the number of substances with which individuals have contact, is vast. This condition is also sometimes referred to as allergic contact dermatitis, if the trigger is an allergen. It is termed as irritant contact dermatitis, if the trigger is an irritant.
Another type of dermatitis is the seborrheic dermatitis. This is a form of skin inflammation and its cause is still unknown. However, some of the potential causes behind development of seborrheic dermatitis include emotional stress, oily skin, infrequent shampooing, weather conditions, etc. The most common signs and symptoms of seborrheic eczema include yellowish, oily, scaly patches of skin. This type of dermatitis can be seen on the scalp, face, and occasionally on other parts of the body. Dandruff in adults and "cradle cap" in infants are examples of seborrheic eczema. This type of dermatitis is not necessarily associated with itching and it tends to run in generations. A type of seborrheic eczema is also found to be common among the AIDS-affected people.
Nummular dermatitis is considered as one of the common types of dermatitis. This is usually a chronic type of dermatitis. This type of dermatitis is characterised by coin-shaped patches of irritated skin, and is most commonly located on the arms, back, buttocks, and lower legs. The skin may be crusted, scaling, and extremely itchy in case of nummular dermatitis. It is relatively uncommon and occurs most frequently in elderly men. The people with a personal or family history of atopic dermatitis, asthma, or allergies have an increased risk of developing nummular dermatitis.
Neuro dermatitis, also known as lichen simplex chronicus, is a common type of dermatitis. This is also a chronic type of dermatitis and is mainly caused by a scratch-itch cycle that begins with a localised itch, like an insect bite. The itch becomes intensely irritated when scratched. Neuro dermatitis affects women more commonly compared to men, and this condition is most frequently found in people aged 20-50 years. The Neuro dermatitis may result in scaly patches of skin on the head, lower legs, wrists, or forearms. In this case, the skin may become thickened and leathery. Mental stress can further degrade the symptoms of Neuro dermatitis.
Another common type of dermatitis is the stasis dermatitis. It is also referred to as varicose eczema. This is a skin irritation, most commonly found on the lower legs. It is generally related to the circulatory problem known as venous insufficiency, where the function of the valves within the veins has been affected. This type of dermatitis occurs almost exclusively in middle-aged and elderly people and the risk of developing stasis dermatitis increases with advancing age. The common symptoms of this type of dermatitis include itching and/or reddish-brown discolouration of the skin on one or both legs. The condition can lead to the blistering, oozing skin lesions seen with other forms of eczema, at an advanced stage and ulcers may also develop in the affected areas. The chronic circulatory problems associated with the stasis dermatitis can lead to an increase in fluid buildup (edema) in the legs.
The Dyshidrotic dermatitis or Dyshidrotic eczema is another common type of dermatitis. It is also known as vesicular palmoplantar dermatitis, dyshidrosis, or pompholyx. In this type of dermatitis, the irritation of the skin is seen on the palms of hands and soles of the feet and it is mainly characterised by clear, deep blisters that itch and burn. The main cause behind development of dyshidrotic eczema is not known. This form of dermatitis is more common among people suffering from hand eczema and commonly develops during the spring and summer months and in warmer climates. The Dyshidrotic dermatitis can equally affect both males and females of any age.
The Psoriasis or psoriatic dermatitis is a type of dermatitis that has distinct relationship to a defined entity, psoriasis. This type of dermatitis can be hereditary and it is also associated with arthritis. Urticaria is another type of dermatitis, which is also known as hives. This is a pattern of allergic dermatitis and characterised by transient wheals or welts. In this type of dermatitis, the lesions may shift, move, or change within 24 hours. Another type of dermatitis is the Vesicular or bullous dermatitis, which is mainly caused by drug reaction or auto immune diseases. Athlete foot fungus can also cause bullous dermatitis of the foot. Steven Johnson Syndrome, bullous erythema multiforme, bullous pemphigoid, and pemphigus vulgaris, etc. are some of the common examples of Vesicular or bullous dermatitis.
Apart from all the above mentioned types, there may be a few other types that are not common but can affect people of all age. Each type of dermatitis has different causes and symptoms and they are treated following different treatment methods, as well.