Seborrheic dermatitis, also known as seborrheic eczema, is a common skin disease and non-serious. This form of dermatitis is a chronic inflammation that occurs in skin areas that contain large numbers of sebaceous glands.
Seborrheic dermatitis does not affect your health in a relevant way, but can be uncomfortable because of the itching, and cause embarrassment when lesions develop on visible parts of the body, as in the case of seborrheic dermatitis on the face.
Seborrheic dermatitis is characterized by rash type skin lesions, red plaques that itch and can flake off. The lesions usually occur in areas with large production of sebum in the skin such as the scalp, face, chest area, ear canal and back. When it affects the scalp, dandruff production is one of its most common signs.
Seborrheic dermatitis is not contagious and is not a poor personal hygiene signal. Touching the injuries will not make you catch the disease.
Seborrheic dermatitis affects about 20% of world population, but only 3% skin lesions are clinically relevant. Men are more affected than women. It is a disease having two peaks of incidence: during the first year of life and after puberty. Once the lesions have appeared for the first time, it becomes a chronic disease that goes back and forth over the decades, with periods of aggravation of injuries, followed by great improvement and disappearance of symptoms.
The cause of seborrheic dermatitis is not fully understood. We know that it is not actually a disease of the sebaceous glands, and the affected patients do not necessarily have an increased production of sebum (oils) by these glands. However, the predilection of seborrheic dermatitis of the skin areas rich in sebaceous glands tells us that these structures are part of the pathophysiological process of the disease.
The theory most widely accepted is that the sebaceous glands, and the oils produced by them, play a permissive role in the pathogenesis of seborrheic dermatitis, possibly by creating a favorable environment for the growth of Malassezia fungi of the genus (formerly called Pityrosporum ovale ). The fungus Malassezia feeds on skin debris and dead prefers areas with higher sebum production. It should be noted, however, that there is still no direct evidence that Malassezia is implicated in the origin of seborrheic dermatitis. This fungus is part of normal flora of the skin germs and may be easily found in many people. Furthermore, patients with seborrheic dermatitis does not necessarily have a larger population of Malassezia fungus in the skin, even in the most severe forms of the disease.
However, how the patient's immune system deals with the presence of Malassezia on the skin is that seems to be the cause of the inflammation and symptom. Malassezia can be irritating to some people genetically predisposed, which explains the occurrence of seborrheic dermatitis only in a small percentage of people colonized by this fungus.
Seborrheic dermatitis is not considered an infectious disease, although there was improvement in symptoms when treated with antifungal medications. No need to fear contact with people with seborrheic eczema, you probably already have the fungus Malassezia on your skin, and do not have dermatitis because your immune system coexists peacefully with it.
Seborrheic dermatitis is characterized by a reddish rash on the skin, usually plates or crusts, and itching associated with skin peeling. Flaking can cause dandruff on the scalp, eyebrows, beard and other regions by as the thoracic region in men.
The scalp lesions may exceed the limits of hair, becoming visible, appearing as slightly elevated crusts or plates, salmon and yellow or silver flaking. There may be hair loss, which usually regress with treatment.
Seborrheic dermatitis on the face usually appear on the forehead, eyebrows, eyelashes, behind the ear, the beard region and around the grooves of the nose and mouth. Involvement around the eyes favors the development of blepharitis, and stye.
The involvement of the ear canal usually cause itching in the ear and favors the formation of cerumen.
The trunk is another area often affected by seborrheic dermatitis. The lesions, usually on rounded plates or geographical format, and affect the heart and the sternum region. Men with chest hair are most affected.
Other areas of the body can also be affected, such as groins, armpits and buttocks.
Seborrheic dermatitis has a chronic character, with periods of improvement and deterioration that persist for decades. The disease tends to worsen in cold, dry weather, fatigue situations or emotional stress after eating fatty foods or alcohol in people who smoke or after hot baths. sunbathing seem to improve the lesions.
There is no cure for seborrheic dermatitis. However, treatments and disease can be controlled so as to hardly cause discomfort to the patient.
Mild cases only with dandruff on the scalp, can only be controlled with anti-capsa shampoo. There are several types of antidandruff shampoo available in the market. The difference between them is the active ingredient. Shampoos with any of the following substances are equally effective after four weeks of use:
Selenium sulfide
Ciclopirox
Salicylic acid
Tar
Zinc pyrithione
Ketoconazole
The shampoo should be left on the hair for at least 5 minutes before rinsing.
If there is no improvement with traditional shampoos, or if the injuries are very intense, a consultation with a dermatologist is necessary. The use of lotions or special shampoos with corticosteroids may be required for the control of injuries.
