Seborrheic dermatitis, also known as seborrheic eczema, is divided into dry seborrheic dermatitis and oily seborrheic dermatitis (both seborrheic diseases are caused by excessive sebum secretion due to hyperfunction of sebaceous glands), and is a chronic inflammatory skin disease that occurs on the head (seborrheic alopecia mostly occurs in men), face, forehead (forehead oil secretion with acne), back, behind the ears and other areas with high sebum secretion. It may be accompanied by varying degrees of itching.
Etiology
The cause of seborrheic dermatitis is unknown, and it has been found to be related to a variety of factors such as physical-climatic factors and medications. Some develop due to neurotransmitter abnormalities, others due to nutritional deficiencies, and others due to seborrhea. Chronic alcohol abuse, poor diet, and mental depression can also trigger the disease.
In addition to excessive sebum production, seborrheic dermatitis has been associated with microbial infections, genetics, vitamin B deficiency, and irrational therapeutic use of medications.
Mechanical irritation and improper use of skin care products can also be “accomplices” in the onset of seborrheic dermatitis. In the present time of advanced information, many articles with the theme of “skin care” are widely spread through WeChat and Weibo, and in these articles, “deep cleansing”, “oil control” and other The keywords “deep cleansing” and “oil control” appear frequently in these articles. We would like to warn you that oil is an important part of the skin barrier, which can block the invasion of harmful substances and neutralize the stimulation of harmful substances, while excessive oil removal can damage the skin barrier and change the skin microenvironment, which is detrimental to skin health. Therefore, it is recommended that you do not use too strong oil removing cleansers.
Recent studies have shown that seborrheic dermatitis is also associated with an increase in Malassezia (also called Bacillus furfuraceus).
Clinical presentation
The disease is often confined, initially on the head, and in aggravated cases may progress to the face, behind the ears, axillae, upper chest, interscapular region, umbilicus, vulva and groin. The initial lesion is a perifollicular inflammatory papule, and as the disease progresses, the papules fuse into yellow-red patches of varying size with clear borders, covered with greasy scales or crusts. The clinical presentation varies depending on the location and severity of the lesions.
Mild lesions on the head are small grayish-white chaffy or greasy scaly patches with a flushed base. Later, the lesions gradually expand and fuse into large map-like patches with clear borders, and in severe cases involve most of the scalp, covered with greasy thick crusts, which may exude and have a fishy odor.
Facial lesions spread from the scalp. The forehead, eyelids, and nasolabial folds are heavily involved, with yellowish-red, greasy, scaly crusts, and sparse eyebrow hair due to scratching. The eyelids are involved in the form of ophthalmoplegia, with the lid margins covered by red, fine white scales. The nasolabial folds and nasal flanks mostly appear as yellow-red greasy patches. In men, the lesions in the beard area may appear as flaky, greasy, scaly erythematous plaques and are often associated with folliculitis. Unilateral or bilateral erythema, swelling, and chancroid may be present behind the ear. Seborrheic otitis externa is commonly seen in older patients.
The trunk lesions are usually found on the chest and between the scapulae, initially as small reddish-brown follicular papules with greasy scales that later fuse into round, oval, or irregular yellowish-red or reddish greasy patches, sometimes with central fading of the patches and peripheral formation of annular or polycyclic damage. There may also be a pityriasis rosea-like lesion pattern.
The lesions on the axillae, vulva, groin, submammary and umbilicus are in the form of disseminated frictional erythema with greasy scales and well-defined borders, often with acute eczema-like changes.
The severity and etiology of seborrheic dermatitis varies from person to person. There are varying degrees of itching. Scratching due to itching can cause secondary infection. Inappropriate topical medications can cause contact dermatitis or eczema-like changes, which can develop into erysipelas in severe cases.
Infantile seborrheic dermatitis: often develops 2 to 10 weeks after birth and occurs on the scalp, face, and nasolabial folds. Eyebrow area. Around the ears and folds. The scalp may be partially or completely covered with greasy grayish yellow or yellowish brown scales or thick crusts of varying thickness, and invades the forehead. Severe cases may be accompanied by vesicles and oozing. Often in 3 weeks to 2 months gradually reduce, healing. For those who persist, the possibility of atopic dermatitis should be considered. May be secondary to bacterial or Candida infection
Infantile seborrheic dermatitis lesions develop suddenly, resulting in erythema and desquamation all over the body, and in severe cases, anemia, diarrhea, vomiting, and secondary bacterial infections. It is called desquamative erythrodermatitis or Leiner’s disease. Those with a family history often have complement deficiencies that lead to dysregulation of the tonin function.
Treatment
Most of the time, seborrheic dermatitis is self-healing, but some patients will have a chronic recurrent process, which requires treatment by a regular professional dermatologist.
1.General treatment
The patient should have a regular life, get enough sleep, regulate diet, limit fatty and sugary diet, avoid alcohol and spicy stimulating food, avoid excessive mental tension.
2.External medicine
(1) Glucocorticosteroids are mainly used for heavier inflammatory lesions, and can be applied externally with medium- or strong-acting glucocorticosteroid preparations, which are effective, but should not be used for a long time, especially on the face. Low-acting glucocorticoid (such as hydrocortisone) preparations are weaker and are suitable for infants and children.
(2) antibacterial drugs topical application of 2% erythromycin ointment or gel, 5% metronidazole cream or cream containing 1% chloramphenicol and 0.1% dexamethasone.
(3) Selenium sulfide lotion has the effect of killing fungi and inhibiting bacterial growth.
(4) Zinc mercaptopyridine shampoo zinc mercaptopyridine shampoo concentration of 1 to 2 percent. In addition to external use on the scalp, it can also be used on other parts, such as the face, the arch of the eyebrows and the trunk. It is not used on the lid margin to avoid irritation of the eyes. The shampoo has an inhibitory effect on the proliferation of epidermal cells. In addition, there is a broad-spectrum antibacterial effect, and can inhibit the growth of oval furfur spores.
(5) antifungal agents antifungal agents, especially imidazole class of drugs have better efficacy. Usually use shampoo or cream containing ketoconazole (2%), itraconazole, econazole, clotrimazole, miconazole, oxyconazole, isoconazole or cyproheptadine and terbinafine (1%) preparations. Antifungal preparations in addition to antifungal, but also anti-inflammatory, antibacterial and inhibit the formation of cell wall lipids and a variety of effects.
(6) sulfur and (or) salicylic acid lotion and other sulfur and (or) salicylic acid has antibacterial, anti-dandruff effect, has a certain effect on the disease.
3.Internal medicine
(1) Glucocorticosteroids such as prednisone, treated in cases with large lesions and heavy inflammation, the course of treatment is usually limited to 7-10 days and should not be too long.
(2) Reglanthoside is suitable for patients with obvious inflammation and large scope. If combined with small doses of glucocorticoids, the effect is better.
(3) AntibioticsInflammatory seborrheic dermatitis lesions with more severe inflammation are often combined with bacterial infection (mainly Staphylococcus aureus infection), sometimes even with pustules and enlarged cervical lymph nodes. Appropriate application of antibiotics is beneficial, such as tetracycline or erythromycin.
(4) B vitamins including vitamin B2, vitamin B6 and vitamin B complex, taken internally for a long time, may be beneficial for this disease.
Warm tip: Please combine the specific medication with the clinical and be guided by the doctor’s face-to-face consultation.