Rosacea

Rosacea is a chronic inflammatory (red, painful, often swollen part of the skin) disease affecting the central area of the face (nose, cheeks, the centre of the forehead, and chin). Rosacea most commonly affects people between 30 and 60 years of age. Females are affected three times more often than males. However, the disorder of phymatous (termed ‘cauliflower’ nose) is more frequent in males.

This disease is characterised by a temporary reddening of the face at the damaged area and by the dilatation of small skin blood vessels. As rosacea develops, the symptoms worsen. Pimples and blisters form along with telangiectasia (visible, permanently dilated blood vessels, also known as spider veins) and patients may suffer from an itching and burning sensation. In certain patients, the disease is accompanied by vision problems.

The exact cause of the disease is unknown, but it is believed that a number of factors are involved in the onset of rosacea. These include a disorder of congenital immunity, changes affecting the blood vessels, digestive system disorders, and the presence of skin microorganisms. It has been proven that individuals affected by rosacea often suffer from allergies, high blood pressure, and cardiovascular (relating to heart and blood vessels) diseases.

A genetic predisposition is one of the key risk factors which leads to the development of rosacea. The genetic predisposition effects may cause congenital disorders of dilatability and the constriction of small blood vessels and produce an abnormal inborn immune response in the skin. The identification of the precise mechanism explaining the association of genetic variants with the development of rosacea is still the subject of research.

Prevalence of rosacea

Rosacea predominantly affects light-skinned people from Northern and Eastern Europe. The prevalence of the condition in children and in persons with darker complexions is rare.
Rosacea is a common skin disease resulting in the reddening of the skin in the central area of the face due to a flush of blood into the affected areas. The degree and duration of the redness of the skin vary depending on the progression of the impairment.

Based on the severity of the symptoms, rosacea has been classified into four categories:

1. Erythematoteleangiectatic rosacea (vascular form) is an initially transient redness of the skin (erythema), which is later transformed into persistent flushing accompanied by telangiectasia (visible, permanently dilated blood vessels). This condition may be worsened by swelling, burning, and tingling.

2. Papulopustulous rosacea (inflammatory form) is characterised by the formation of pimples and blisters on persistently reddened skin. This type is similar to acne but without comedones (blackheads or whiteheads) present. Sometimes, this type of rosacea may manifest itself in a slight swelling of the subcutaneous tissue of the face (under the skin).

3. Phymatous rosacea (hyperplastic form) is typical of the development of large inflammatory foci (central point), accompanied by hypertrophy (the enlargement of the tissue due to an increase of cell size) of the connective tissue and sebaceous glands (skin glands which secrete oily matter). The result is a toughening and thickening of the skin to cauliflower hypertrophy, commonly on the nose (rhinophyma).

4. Ocular rosacea is associated with eye complications and develops in about 20% of those persons affected by rosacea. Ocular rosacea may manifest itself by increased tear production, burning sensation in the eyes, blurred vision, stinging in the eye, dryness, and the sense of a foreign body in the eye.

Pathophysiology of rosacea

The exact mechanism of rosacea development remains unknown, but it is a comprehensive process induced by a number of pathological changes along with provocative factor effects. In individuals suffering from rosacea, disorders of the immune system arise, resulting in the abnormal release of inflammatory cytokines and the production of antimicrobial peptides (AMPs).

Skin affected by rosacea shows a marked production in cathelicidin. Cathelicidin, produced by the cells of the immune system, is an important defence in the response to bacteria. Cathelicidin is split into the active molecule (LL-37) by an enzyme (serine protease KLK5). In individuals affected by rosacea, these molecules (LL-37 and KLK5) are altered, which leads to changes in the vasodilatation process (blood vessel dilatation), angiogenesis (neovascularization), and deposition (forcing out) into the extracellular matrix (situated outside cells).

An increased number of enzymes (collagenases, elastases) causes inflammation, damage to the vessel wall, and skin hypertrophy (tissue enlargement due to cell size increase). It is believed that these changes and the subsequent swelling promote the colonisation and spread of the Demodex folliculorum acarid (follicle mites) and other microorganisms. The presence of these organisms in hair follicles (a small secretory gland located at the hair follicle) may lead to their clogging and to blister and pimple formation.

Follicle mite (Demodex folliculorum)

The follicle mite is a mite living in human hair follicles (position where body hair grows) and in the sebaceous glands (secretes oily matter) of its hosts. This parasite occurs in the area of the chin, nose, forehead, and back. It is assumed that most of the human population is affected. The probability of infection increases with age. At 60+ years of age, over 50% of the population is reported to host an average contagion (spread by close contact, i.e. sharing common towels).

History of rosacea

Rosacea was described in the literature in medieval Britain in The Canterbury Tales. According to some sources, the Greek poet Theocritus mentioned the disease in the 3rd century BC. The Italian painter Ghirlandajo (1449-1494) clearly depicted the condition of rhinophyma in his portrait of an old man on the painting An Old Man and His Grandson, currently exhibited in Paris at the Louvre.

The first person who referred to rosacea as a health condition was the French surgeon Dr. Guy de Chauliac, who observed distinctive red areas on the faces of some patients. This condition was called goutterose (meaning pink droplets) as well as couperose, a French term describing this disease still currently used.

Treatment options for rosacea

The treatment of rosacea is a lengthy process with relatively slow improvements in the symptoms. At the outset, ocular rosacea is nearly invisible. It causes short-term redness in the central area of the face particularly when exposed to sunlight, consuming hot drinks, and during strong emotional fluctuations. However, symptoms may gradually deteriorate. Therefore, it is advisable to visit an ophthalmologist (eye disease specialist) if any of the initial symptoms occur.

The treatment itself is very comprehensive and is specific to each individual person. The treatment should include the education of the patient about the impairment, identification of the factors that aggravate the symptoms of rosacea (provocative factors), and information about prevention, choice of appropriate skin care products, and suitable treatment options. The treatment is also specific to the stage of the disease itself.

In the first stage, local applications of medical creams are used, namely gels and creams containing topical antibiotics and antimycotics, which prevents the growth of fungi (i.e. metronidazole, azelaic acid, tetracyclines, and erythromycin). These substances have an anti-inflammatory effect and suppress bacterial growth on the skin. For maintenance treatment, lotions containing sulphur and ichthammol are applied. In more serious cases, systemic antibiotic treatment, laser treatment, or surgery are chosen.

In the case of ocular rosacea, the application of eye drops and antibiotics is recommended. Alternatively, laser treatment methods, intensive pulse light sources, or other medical and/or surgical means may be used to remove small visible blood vessels and to reduce excessive redness.