How to determine if you have seborrheic dermatitis

Symptoms

Seborrheic dermatitis occurs most frequently within the first 3 months of life and between the ages of 40 and 70. In infants, there is no difference between genders, but in adults, it is more common in males and is associated with oily skin.

It is characterized by dry or oily yellow scales (scales) that occur on the erythema, and it may be accompanied by itching. It can recur with improvement and worsening, and may appear all over the body, but it can also present as a rash confined to one area. On the scalp, there may be rice bran-like epidermal peeling, which is called dandruff.

Seborrheic dermatitis of the face may present as papular eruptions (raised bumps less than 1cm in size) on the cheeks, nose, and forehead. Scales that easily peel off and erythema are found on the eyebrows, and the skin beneath the scales appears red. The eyelids may also appear yellowish-red and be covered with fine scales.

Seborrheic dermatitis that develops in the ear can be misdiagnosed as otitis externa (outer ear canal infection) caused by infection. On the outer ear canal, scales accompanied by severe itching can occur, and it may also affect the skin behind the ear and below the earlobe. In the armpit area, a rash begins bilaterally from the nipple and spreads to the surrounding skin, resembling allergic contact dermatitis caused by deodorants. In the groin and between the buttocks, the scales are fine, with less distinct borders, and tend to be bilateral and symmetrical. Cracks may also develop in areas where the skin overlaps.

Yellow or brown lesions that accumulate and stick together on the scalp of infants are called baby hair oil.

Cause

The exact cause of seborrheic dermatitis has not yet been definitively identified, but there are several theories.

First, it is a theory that sebum is directly or indirectly involved in the occurrence of the disease. This claim is supported by the fact that the disease commonly appears in areas with well-developed sebaceous glands and occurs during infancy and adulthood when sebaceous gland activity is high.

Secondly, the theory that bacteria and yeast are the causes of seborrheic dermatitis. However, this hypothesis has not gained support despite the detection of large amounts of bacteria and yeast in the affected areas. This is because, in inflammatory seborrheic dermatitis, the detection rate of Pityrosporum was actually lower than normal, and the spore count was also low, making it difficult to conclude that Pityrosporum is the direct cause of seborrheic dermatitis.

Third, it is a theory that is associated with abnormalities in neurotransmitters. This is because seborrheic dermatitis frequently occurs in patients with nervous system disorders.

Fourth, there is a theory that seasonal changes in temperature and humidity are related to the occurrence of the disease. In fact, symptoms are known to worsen in environments with low temperatures during autumn and winter, and low humidity caused by central heating.

Fifth, it is a theory that abnormal proliferation of the epidermis is the cause of the disease. This is because, in seborrheic dermatitis, epidermal proliferation increases similarly to psoriasis, and symptoms improve when drugs that inhibit cell proliferation are used.

In addition, there is a hypothesis that attributes the cause to drugs and nutritional deficiencies, based on the fact that medications such as neuroleptics, cimetidine, gold, and methyl dopa can cause lesions similar to seborrheic dermatitis; that zinc deficiency can lead to enteropathic stomatitis; and that prolonged reliance solely on intravenous fluids for nutrition can result in symptoms resembling seborrheic dermatitis on the face.

Related body organs

Skin areas with well-developed sebaceous glands and high sebum production, such as the scalp, face, armpits, and chest.

Diagnosis

Generally, no special tests are necessary, and diagnosis can be made based on the appearance and distribution pattern of characteristic symptoms.
It is important to distinguish it from psoriasis, which presents with erythema, thick scales, bleeding points when scales are removed, and commonly occurs at the front of the head and the edges of the scalp. Psoriasis does not cause hair loss, pain, or itching, but may be accompanied by characteristic symptoms in other areas such as changes in the fingernails and toenails.

Test

Generally, it is diagnosed through physical examination. In cases of chronic seborrheic dermatitis that do not respond to treatment, skin biopsies and other tests should be performed to differentiate from other diseases and to identify any associated conditions. When a biopsy is conducted, findings of scales and crusts partially appearing around hair follicles are observed.

Treatment

In seborrheic dermatitis, treatment of the scalp is particularly important. The scalp can be effectively treated by washing 2 to 3 times a week with a cleanser containing ketoconazole, selenium sulfide, or zinc pyrithione, and applying steroid-based lotions, solutions, or gels to the scalp is also effective. For areas without hair, steroid creams are most effective, and in severe cases with bacterial infection, steroid preparations containing antibiotics are effective. However, it should be noted that long-term use of potent steroids on the face can cause side effects, and since it is a chronic condition, systemic administration of steroids should generally be avoided.
In cases of infants' scalps, apply olive oil as a compress to remove scabs and use a low-concentration steroid for a short period.

Progression/Complications

The course of the disease is characterized by repeated episodes of improvement and worsening, and symptoms can also worsen due to excessive stress, fatigue, or scalp irritation. Therefore, treatment should be maintained consistently not for complete cure but for the suppression and prevention of symptom occurrence, and sufficient rest for psychological stability and fatigue prevention is necessary.

Prevention methods

Prevention is not possible, but the frequency and number of recurrences can be reduced by avoiding stress, overwork, smoking, and alcohol consumption.

Living Guide

Seborrheic dermatitis requires maintaining cleanliness of the hair and skin as a priority, and it is essential to remove excess oil and dust from the scalp to eliminate aggravating factors. Additionally, severe scalp inflammation can lead to significant hair loss, so avoiding alcohol and overexertion is important for self-care. It is also crucial to seek proper treatment at the onset of symptoms such as dandruff or itching on the scalp. On the face, avoid using oily ointments or cosmetics, reduce the frequency of soap use, and refrain from using alcohol-based aftershave lotions before and after shaving. Reducing physical fatigue and stress is necessary. The frequency of hair washing should be about five times a week in severe cases, and about three times a week during normal times; using shampoo is preferable to soap. Medicinal shampoos can make hair coarse, so it is recommended to use them about twice a week. Products like mousse, spray, and gel tend to combine with scalp oils and skin cells, irritating the scalp, so it is best to avoid using them if possible. Sweating from intense work or exercise can irritate the scalp and cause skin cells to shed more quickly, so it is advisable to shower and wash the scalp promptly afterward.

Source:Medical Information on N (Seborrheic Dermatitis) | Seoul National University Hospital

I think it's nothing special, so I often wash and apply lotion, thinking it will get better, but then I go to the hospital.
I received prescriptions for both oral medication and topical medication...
These days, because the environment is not good, seborrheic dermatitis has become very common...
Please don't neglect it and go to the hospital~