Learn about Demodex dermatitis

Demodex dermatitis is caused by demodex articular insects that are parasites in humans and animals of the sebaceous hair follicles. For healthy people, skin scales and hair follicles are 2 locations of pathogenic Demodex bacteria.

1. What is Demodex bacteria?

Demodex bacteria that cause dermatitis in humans have two types: Demodex folliculorum and Demodex brevis. In terms of demodex folliculorum size: Adults can grow up to 440um long and demodex brevis can reach 240 um, however they are not visible to the naked eye but can only be observed under an optical microscope.

Demodex consists of a tail head and 4 pairs of legs near the head with a life cycle: 14 – 24 days. Its life cycle has 5 stages: eggs, larvae, pre-pupae, pupae and adults.

Demodex usually lives in pairs, after intercourse, the bacteria on the skin of the face go deep inside the skin and lay eggs in the position of hair follicles or sebaceous glands, carrying bacteria and excreting waste, dying in the skin immediately after laying eggs. After death, their corpses become laxative and decompose on the surface of the skin, and cause allergic reactions in some parts of the skin tissues, red spots (acne) occur local alleritis, encephalitis, encephalitis and pustules. These are all reactions by the immune system.

Demodex dermatitis is spread through direct contact or may be caused by dust containing eggs attached to the surface of the skin, or shared items, kissing, cheek brushing, the use of a common face towel.

Demodex bacteria

Demodex bacteria

2. Classification of demodex dermatitis

Demodex is a bacteria on the skin of the face that can survive a healthy human body without any characteristic clinical manifestations, but will cause disease when large numbers of bacteria are concentrated on the surface of the skin, skin scales, hair follicles or when the body's immunity declines. Demodex dermatitis consists of 3 common diseases:

  • Exfoliative folliculitis (mildest): lesions are red skin, the surface has skin scales, buttons in the hair follicles, patients have a sensation of ants crawling on the skin.
  • Caviar demodex dermatitis.
  • Granules of red caviar (this is rare, common in people with weakened immune systems).

Two types of a caviar demodex dermatitis and psoriasis folliculitis are caused by the use of cosmetics that in cosmetics contain corticoids used for a long time from floating products, of unknown origin. The ingredients of these cosmetics are the cause of dermatitis, skin atrophy, dilation, caviar rash and demodex dermatitis.

Classification of demodex dermatitis

Demodex bacteria cause demodex dermatitis

3. Symptoms of demodex dermatitis

Symptoms of demodex dermatitis:

  • Redness of the skin
  • Pustules
  • Red-ede
  • Vascular dility
  • The pores on the nose, chin, forehead and cheeks become wider, after a while the skin of the face can become red, the capillaries float thickening to the sides of the nasal wings.
  • Loss of eyebrows, eyelashes, hair loss, lash inflammation, itching (crawling ant sensation), burning of the lesion area.
  • Sensation of ants crawling on the skin of the face: Appearing on the forehead, nose, cheeks, especially in the evening and at night caused by bacteria mating on the surface of the skin, there are many scratches on the surface of the patient's skin that they do not recognize.
  • Itching on the scalp is the cause of scalp abrasions, such as lice and dandruff (which should be excluded to determine the appropriate treatment).
  • Hair loss: in some cases, early hair loss may be associated with the activity of Demodex bacteria at the pores on the surface of the skin.

Juvenile demodex dermatitis is often misdiagnosed as juvenile acne. Demodex dermatitis can be repeated and severe so after healing often leaves the skin of the face rough and ugly.

Demodex bacteria

Photos of patients with demodex dermatitis

4. How to treat demodex dermatitis?

4.1 Principles of treatment

  • Remove demodex ticks on the surface of the skin as soon as possible and fight further infections.
  • Treatment should be started early because demodex dermatitis is highly contagious and spreads quickly through hugging, kissing, using a common face towel.
  • People infected with demodex dermatitis with no visible signs can also transmit bacteria on the surface of the skin to others. Once infected, the incubation period can take months or even years.
  • Minimize the use of cosmetics during the treatment of the disease. This is because this bacterium is capable of multiplying very quickly in a cosmetic-applied skin environment.

In addition, patients need:

  • Wash your face every day
  • Avoid the use of oil cleaners and lubricant makeup
  • Regular exfoliating to remove dead skin cells
  • Use of drugs prescribed by a doctor

To register for examination and treatment at Share99 International Health Hub, you can contact Share99 Health System nationwide, or register for an online examination HERE.


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About: Minh Quynh

b1ffdb54307529964874ff53a5c5de33?s=90&d=identicon&r=gI am the author of Share99.net. I had been working in Vinmec International General Hospital for over 10 years. I dedicate my passion on every post in this site.


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