Learn about Demodex dermatitis

Demodex dermatitis is caused by the arthropod insect Demodex parasitic in humans and animals in the area of ​​sebaceous hair follicles. In healthy people, skin scales and hair follicles are two sites of Demodex bacteria that cause disease.

1. What is Demodex bacteria?

Demodex bacteria that cause dermatitis in humans are of two types: Demodex folliculorum and Demodex brevis. About the size of demodex folliculorum bacteria: Adults can be up to 440um long and demodex brevis can reach 240um, but they are all invisible to the naked eye and can only be observed under an optical microscope.
Demodex consists of head and tail and 4 pairs of legs near the head with a life cycle: 14-24 days. Its life cycle has 5 stages: egg, larva, pre-pupa, pupa and adult.
Demodex usually live in pairs, after intercourse, bacteria on the skin of the face go deep inside the skin and lay eggs at the location of hair follicles or sebaceous glands, carrying bacteria and excreting waste, dead inside skin immediately after laying eggs. After death, their carcasses liquefy and decompose on the surface of the skin, and cause allergic reactions in some parts of the skin tissues, red spots (acne) occur atopic dermatitis in the skin. spots, erythema, papules and pustules. These are all responses by the immune system.
Demodex dermatitis is spread by direct contact or can be caused by dust containing eggs clinging to the surface of the skin, or shared utensils, kissing, rubbing cheeks, using shared towels.
Vi khuẩn demodex
Vi khuẩn demodex

2. Classification of dermatitis due to demodex

Demodex is a bacteria on the skin of the face that can exist in a healthy person's body without any specific clinical symptoms, but it will cause disease when a large number of bacteria are concentrated on the surface of the skin, scales, and follicles. hair or when the body's immunity is weakened. Demodex dermatitis consists of 3 common diseases:
Powdery mildew folliculitis (the mildest form): the lesion is a red patch of skin, the surface has scaly skin, the horny button in the hair follicle, the patient has a cold. ants crawling on the skin. Acne demodex dermatitis. Granulomatous rosacea (this form is uncommon, usually in people with weakened immune systems). The two types of acne demodex dermatitis and psoriatic folliculitis are caused by the use of cosmetics that contain corticosteroids for long-term use from floating products of unknown origin. The ingredients of these cosmetics are the cause of dermatitis , skin atrophy, vasodilatation, acne rash and demodex dermatitis.
Phân loại viêm da do demodex
Vi khuẩn demodex gây bệnh viêm da do demodex

3. Symptoms of dermatitis caused by demodex

Symptoms of dermatitis caused by demodex:
Red patches of skin Pussy red papule rash Vasodilation Pores on the nose, chin, forehead and cheeks become wider, after a while the skin of the face can become discolored red, thickened capillaries on both sides of the nose. Loss of eyebrows, eyelashes, hair loss, blepharitis, itching (crawling sensation), burning in the affected area. Feeling of ants crawling on the face: Appears on the forehead, nose, cheeks, especially in the evening and at night, caused by bacteria mating on the surface of the skin, many scratches appear on the surface of the skin. patients they do not recognize. Scalp itching is a common cause of scalp abrasions, such as head lice and dandruff (should be ruled out to determine appropriate treatment). Hair loss: In some cases, premature hair loss may be related to Demodex activity in the pores on the surface of the skin. Juvenile demodex dermatitis is often misdiagnosed as juvenile acne. Demodex dermatitis can recur many times and is so severe that after healing, it often leaves the face rough and ugly.
Vi khuẩn demodex
Hình ảnh bệnh nhân bị viêm da do demodex

4. How to treat demodex dermatitis?

4.1 Principles of Treatment Remove the demodex mite from the surface of the skin as soon as possible and prevent further infection. Treatment should be started early because demodex dermatitis is highly contagious and spreads quickly through hugging, kissing, and using shared towels. People infected with demodex dermatitis who have no visible symptoms can also transmit bacteria on the surface of their skin to others. Once infected, the incubation period can take months or even years. Minimize the use of cosmetics during treatment. The reason is that this bacteria has the ability to multiply very quickly in the skin environment where cosmetics are applied. In addition, the patient needs to:
Wash the face every day Avoid the use of oily cleansers and greasy makeup Exfoliate periodically to remove dead skin cells Use medications as prescribed by the doctor. Doctor To register for examination and treatment at Vinmec International General Hospital, you can contact Vinmec Health System nationwide, or register online HERE.
Package of examination and advice on treatment of atopic dermatitis Atopic dermatitis: What you need to know Children with atopic dermatitis: How to take care of it properly?
Bài viết này được viết cho người đọc tại Sài Gòn, Hà Nội, Hồ Chí Minh, Phú Quốc, Nha Trang, Hạ Long, Hải Phòng, Đà Nẵng.

310 lượt đọc

Dịch vụ từ Vinmec

Bài viết liên quan