Seborrheic dermatitis
What is seborrheic dermatitis? Learn about the symptoms, causes, and treatment for this type of endogenous eczema.
Symptoms and causes
Seborrheic dermatitis is a chronic inflammatory skin disease of multifactorial origin, associated with alterations in the function of the sebaceous glands and the skin flora.
It is a condition caused by the body itself, in which endogenous and exogenous factors influence its onset and progression.
This disease affects both adults and children, especially infants (cradle cap), and usually appears more intensely during periods when hormones stimulate sebaceous activity.
Seborrheic dermatitis develops in areas of the body with a higher density of sebaceous glands, such as the face, eyebrows, eyelids, beard area, ears, behind the ears, nasolabial folds, scalp, chest, back, or groin.
Symptoms
The symptoms associated with seborrheic dermatitis include:
- Redness and scaling of the skin in sebaceous areas (scalp, face, eyebrows, nose, ears, chest, and back). When it occurs on the scalp, the scaling is referred to as dandruff.
- White or yellowish scales.
- Rash.
- Itching, irritation, and discomfort.
- Redness.
- In rare cases, hair loss.
Causes
The causes of seborrheic dermatitis are still unknown, although the following factors are believed to play a role in its development:
- Genetic predisposition.
- Increased sebum production due to hormonal changes.
- The effect of Malassezia fungi, naturally present in areas of the skin with a higher number of sebaceous glands and usually harmless.
- External factors such as stress, climate, and certain neurological disorders.
Risk factors
The most significant risk factors for seborrheic dermatitis include:
- Hormonal changes (infants are affected by maternal hormone levels).
- Stress.
- Fatigue.
- Acne.
- Exposure to extreme climates, especially heat.
- Psoriasis.
- Nervous system disorders, particularly Parkinson’s disease, stroke, or head trauma.
- HIV (human immunodeficiency virus).
- Alcohol consumption.
Complications
Complications associated with seborrheic dermatitis are usually related to mental health:
- Low self-esteem.
- Depression.
- Anxiety.
- Social isolation.
When itching is intense and the patient scratches the eczema, sores may develop that promote bacterial or fungal infections. If these spread throughout the body—which is uncommon—they can become life-threatening.
Prevention
Seborrheic dermatitis cannot be prevented. Nevertheless, it is advisable to follow certain recommendations to control flare-ups and reduce symptoms:
- Maintain good hygiene.
- Shower instead of bathing, preferably with lukewarm or cold water.
- Use neutral soaps that do not contain alcohol.
- Avoid oily cosmetics.
- Manage stress.
- Avoid alcohol and spicy foods.
- Avoid heat and limit direct sun exposure, although small doses are beneficial.
Which specialist treats seborrheic dermatitis?
Seborrheic dermatitis is treated within the specialty of dermatology.
Diagnosis
The diagnosis of seborrheic dermatitis is clinical and based on the following procedures:
- Patient interview: anamnesis helps to identify the patient’s medical history, family background, and reported symptoms.
- Physical examination: observation of eczema and scaling, as well as other areas prone to these lesions.
- Symptom comparison with other types of dermatitis.
- Skin biopsy: when other conditions need to be ruled out, a skin sample is taken for laboratory analysis.
Treatment
There is no definitive cure for seborrheic dermatitis, so treatments focus on preventing flare-ups and relieving symptoms when they occur.
- Over-the-counter cosmetics: gels, creams, and shampoos specifically designed to treat dandruff or dermatitis. They usually contain zinc, acetylsalicylic acid, selenium sulfide, or resorcinol.
- Prescription cosmetics: in more severe cases, products with higher concentrations of medication (corticosteroids, pimecrolimus, ketoconazole, or sodium sulfacetamide) are required to control inflammation or modulate immune system function.
- Antifungal medications: in severe or persistent cases, these drugs may be administered orally to prevent fungal infections.
- Phototherapy: in resistant or severe cases, phototherapy takes advantage of the beneficial effects of sunlight to reduce inflammation and improve the appearance of eczema. Special devices are used to expose the skin to UVA or UVB rays in a controlled manner.
