Demodex folliculorum and Demodex brevis are two species of tiny parasitic mites that live in the hair follicles and sebaceous glands of human skin, respectively. Both species are found primarily on the eyelashes and eyebrows or near the nose. Demodex infestation is relatively common, and is only rarely associated with disease. Occasionally, mite populations can expand, resulting in a condition called demodicosis, which causes itching and inflammation. Demodicosis most commonly occurs in individuals with a compromised immune system. Demodex are also implicated in some instances of rosacea, possibly due to bacteria carried by the mite, although the link between Demodex and this inflammatory skin condition is not fully understood.
Demodicosis results in non-specific symptoms and signs on facial skin. These most often include:
- Follicular scales
- Sensitive skin
Macules , papules , eczema , folliculitis and pigmentation have also been described.
Patients with demodicosis may have eye irritation, itching and scaling of eyelids (blepharitis or eyelid dermatitis ). There may be lid thickening, loss of lashes ( madarosis ), conjunctival inflammation and decreased vision.
Increased numbers of Demodex mites have been observed in the following conditions:
- Demodex folliculorum – rough skin due to increased scale within hair follicles
- Demodectic frost of the ear – frosted, gritty follicular scaling of the ear lobe and helix , particularly asymmetrical papulopustular or granulomatous variants
- Some cases of perioral dermatitis (also affecting periorbital or periauricular sites) (auricular demodex)
- Demodex abscess
Rosacea due to demodicosis
The skin condition known as demodex folliculorum is also known as pityriasis folliculorum or spinulate demodicosis. It is a form of digitate keratosis , with slight redness and sandpaper-like texture of the skin due to follicular scale. It can cause irritation and burning sensation.
Generally, you may not know if you have high concentrations of D. folliculorum on your skin until they experience a flare-up. That’s because these microscopic mites aren’t detectable with the naked eye. To diagnose D. folliculorum, your doctor will take a small tissue sample.
The doctor collects the sample by scraping the affected skin. They then examine it under a microscope.
This helps the doctor diagnose a D. folliculorum flare-up. Depending on the number of D. folliculorum, your doctor will prescribe treatment.
Dado que D. folliculorum no es visible a simple vista, deberá consultar a un médico para obtener un diagnóstico definitivo. Para diagnosticar estos ácaros, su médico raspará una pequeña muestra de tejidos y aceites foliculares de su cara. Una biopsia de piel que se muestra bajo un microscopio puede determinar la presencia de estos ácaros en la cara.
Las personas que tienen grandes cantidades de ácaros en la cara pueden ser diagnosticadas con demodicosis. Los síntomas de la demodicosis incluyen:
- escamas alrededor de los folículos pilosos
- piel roja
- piel sensible
- picazón en la piel
Su médico puede recetarle una crema que puede ayudar a eliminar los ácaros y sus huevos.
D. folliculorum también puede causar complicaciones con afecciones cutáneas preexistentes. Puede empeorar los brotes de acné, las erupciones por rosácea y los parches de dermatitis. El control de los ácaros puede ayudar al resultado de este tipo de afecciones inflamatorias de la piel.
The Demodex folliculorum mite is a type of parasite that lives on humans. Most of the time, these mites are harmless and will go unnoticed. However, larger numbers of D. folliculorum mites can cause unwanted symptoms and skin problems.
D. folliculorum mites live in or around hair follicles, feeding on the dead skin cells, oils, and hormones that build up there. These mites usually live on the face, including the eyelids and eyelashes.
D. folliculorum mites are more common in males than in females, with people aged 20–30 years old the most likely to be affected.
In this article, we look at what causes D. folliculorum mites to become a problem and the conditions associated with their presence. We also cover diagnosis and treatment, including home remedies.
Share on Pinterest A magnified image of the D. folliculorum mite on a human eyelash.
Image credit: Vladimir064, 2017
D. folliculorum mites are usually harmless but can cause problems for people with weakened immune systems.
Therefore, people at risk of experiencing symptoms include those who:
- are taking corticosteroids, such as prednisone
- have a history of cancer or liver disease
- are living with HIV
Some other people may be genetically susceptible to D. folliculorum and thus more sensitive to the presence of the mites.
Also, D. folliculorum mites are sometimes present in greater numbers in people with certain skin conditions. Examples of these include:
Rosacea is an inflammatory skin condition that causes facial flushing, redness, and dry lesions on the face.
Some studies have found that a person with rosacea can sometimes have four times more Demodex mites on their face than someone without the condition. Among people with rosacea, those with subtype 1 are more likely to have a high number of these mites on their skin.
D. folliculorum mites have also been found in the tear ducts of people with ocular rosacea, which is a type of rosacea that affects the eyes.
Blepharitis is an inflammation of the eyelids that can cause crusting, watering, and redness. Increased numbers of Demodex mites have been noted in people with blepharitis.
Androgenetic alopecia is an inherited hair-loss condition that affects both men and women. It has been suggested that a chemical produced by the mites may trigger an inflammatory reaction that affects hair follicles. Although Demodex mites do not cause androgenetic alopecia, they may worsen the condition.
Non-specific facial dermatitis
Increased numbers of Demodex mites are also associated with symptoms of non-specific dermatitis on the face. These symptoms include itching, acne-like blemishes, and spots around the lips.
Large numbers of D. folliculorum mites can cause rosacea-like symptoms on the skin of the face. These symptoms include:
- acne-like blemishes
- rough-feeling skin
- eye redness
The symptoms caused by D. folliculorum mites are sometimes mistaken for acne or severe skin dryness.
A doctor will start the diagnosis of D. folliculorum by taking a medical history and examining the skin.
The mites are too small to be seen with the naked eye, so the doctor will usually do a skin biopsy. This involves taking a sample of the skin and examining it under a microscope.
It is important to determine the quantity of mites living on the skin. A small number of mites is unlikely to be the cause of an individual’s skin problems.
D. folliculorum mites are more likely to occur on the face. This can make treatment more challenging because the skin there is very sensitive.
A doctor may recommend treatment with creams such as crotamiton or permethrin. These are topical insecticides that can kill mites and so reduce their numbers. The doctor may also prescribe topical or oral metronidazole, which is an antibiotic medication.
A person can clean around their eyes using Demodex facial wipes or towelettes. Suitable products include Cliradex and Demodex Control. These products and others are available online.
Doctors may also apply a high-concentration alcohol solution to a person’s face. This brings the Demodex mites to the surface. The doctor can then apply substances to the skin that kill the mites and treat the condition.
For people who have a severely weakened immune system, a doctor may prescribe ivermectin.
There are also some preventive measures that a person can take at home. These include:
- Washing the face twice daily with a gentle cleanser. Scrubbing the eyelids with baby shampoo may also help.
- Avoiding oil-based cleansers and greasy makeup, which can provide further “food” for the mites.
- Exfoliating once or twice a week to remove dead skin cells.
Keeping the skin clean and dry as well as addressing any underlying conditions may help to reduce the number of D. folliculorum mites.
For most people, the presence of D. folliculorum mites on the face is harmless.
However, in larger numbers, these mites can cause rosacea-like symptoms. Individuals with certain skin conditions or weakened immune systems are at greater risk of developing these symptoms.
A doctor can do a skin biopsy to determine if a person is living with an abnormally high level of mites. Treatment involves cleaning the face regularly and using various medications to kill the mites.
Лечение глаз и век может принести быстрое облегчение людям, многие из которых страдали от клеща, блефарита или сухости глаз в течение многих лет.
Но есть средства, которые больные могут применять у себя дома, чтобы еще больше уменьшить проблему. Рекомендуется стирка простынь и наволочек в горячей воде и сушке при высокой температуре, чтобы убить клещей, которые способны перемещаться с постельных принадлежностей к лицу. В некоторых случаях имеет смысл купить новые подушки. Можно также отказаться от макияжа в течение недели, и выбросить старую косметику.
Многие врачи обеспокоены тем, что пациенты не будут соблюдать процедур, которые они рекомендуют. Но стоит только описать людям, как паразиты закапываются в их клетки и пируют на их телах, особенно, если показать фотографии микроскопических существ, то они сразу же готовы соблюдать рекомендации. Если лечение раздражает, как, например, продуктами из масла чайного дерева, то многие от него отказываются. Но если с терапией человек чувствует себя комфортно и ощущает веки более свежими, то он более склонен придерживаться режима.