Redness: When should you consult a dermatologist?

Redness and rosacea both manifest themselves through the presence of redness on the face. Despite this similarity, there are fundamental differences.

Redness is a physiological condition during which the face, or other parts of the body, take on a more or less intense red color. This phenomenon indicates a significant blood flow, when the blood capillaries that irrigate the skin excessively dilate at the level of the dermis. They are generally observed on hypersensitive skin, due to an altered skin barrier and hyper-reactivity of sensory fibers, whereas they would not necessarily have manifested on normal skin.

Unlike physiological redness, the rosacea is a chronic skin disease that can manifest in 4 different forms: vascular, ocular, papulopustular, or hypertrophic. The presence of facial redness, due to an exaggerated reaction of the blood vessels, is the common point among the 4 forms, but other symptoms may appear.

Redness being physiological, the symptoms generally limit themselves to a redder skin. On the contrary, rosacea being a disease, other signs are observed and complicate the daily life of those affected. Thus, when these signs are observed, it is essential to consult a dermatologist so that they can make a diagnosis and prescribe an appropriate treatment.

Rosacea is a chronic skin disease that affects approximately 4 million people in France. This condition predominantly affects women and individuals with a light phototype (light skin, light eyes, light hair).

As previously mentioned, there are 4 forms of rosacea. There are specific signs for each type of rosacea:

• Vascular rosacea or telangiectasia:

Rosacea is themost common form of rosacea. It is characterized by temporary redness (erythema) or permanent redness (erythrosis) associated with the development on the skin's surface of small, fine, red or purple blood vessels that become visible to the naked eye (telangiectasias). These rednesses are located in thecenter of the face (forehead-eyes-nose-cheeks-chin).

This condition is accompanied by skin dryness and a significant sensitivity of the skin. This skin sensitivity is due to a high number of nerve endingsin the deeper part of the skin and the presence of a substance called "substance P"which is found locally and in the blood, leading to local inflammation.

In addition to redness, rosacea is accompanied by repeated sensations of hot flashes (flushes) that occur under certain conditions (consumption of alcohol, spicy foods, etc).

An extra-cutaneous sign manifests in 1 out of 3 people: ocular burning (a constant sensation of having a grain of sand in the eye).

• Ocular Rosacea:

In 30 to 50% of cases, individuals with rosacea develop an ocular condition.

Ocular rosacea can sometimes precede skin involvement. It presents itself in the form of conjunctivitis, eye irritation, eyelid inflammation (blepharitis), teary red eye (conjunctival hyperemia), a burning sensation, dryness with a feeling of a foreign body in the eyes and light sensitivity (photophobia).

This ocular condition would be due to the malfunction of the Meibomian glands. These glands are located along the eyelids and secrete an oily substance responsible for the lubrication of the eyes.

• The Papulopustular Form:

This form is recognized by redness accompanied by inflammatory lesions similar to acne lesions : the papules and pustules.

The papules are inflammatory red bumps without pus that are less than 5 mm. They can be round or oval in shape and are often painful. They are possibly caused by the invasion of the sebaceous gland by Demodex Folliculorum, a parasite typically found in the follicle.

Unlike papules, the pustules are characterized by the presence of pus. These are red bumps with a white head containing pus.

These lesions progress in flare-ups. In other words, the redness persists and the papules and pustules recede. However, during subsequent flare-ups, the number of papulopustular lesions increases and the flare-ups become more and more frequent.

Note : There is a very rare form of rosacea characterized by the presence of numerous painful pustules and nodules: this is the fulminant rosacea. It generally appears in women aged 30-40 years, during pregnancy, following Crohn's disease, or after treatment with interferon alpha.

• The Hypertrophic Form:

The hypertrophic form is the rarest form of rosacea and generally affects men.

A fibrosis of the dermal tissues is observed. The sebaceous glands of the nose increase in size and the pores dilate. The nose is the part of the face most affected by these deformations known as rhinophyma.

The skin thickens, forming fleshy protrusions or swellings that are very unsightly.

Note : fibrosis is the result of an inflammatory process triggered by tissue damage.

Although the signs and symptoms of rosacea can manifest in various ways, it typically begins with transient facial redness.

Regrettably, these redness episodes recur and become more intense and last longer each time. Visible blood vessels may eventually appear.

In the absence of treatment, bumps and pimples often develop, spreading over time, and in the most severe cases - especially in men - the nose can become swollen and enlarged due to excess tissue. In some individuals, the eyes are also affected: this is ocular rosacea.

The only way to treat this chronic medical condition is to consult a dermatologist at the first signs of its appearance. The dermatologist can confirm the diagnosis and assess the stage of the disease. They will then prescribe a treatment that is suitable for your case.

The treatment varies depending on the stage of the disease:

• For minor forms, the dermatologist prescribes topical treatments based on ivermectin, azelaic acid or metronidazole. The brimonidine is a new vasoconstrictor treatment in gel form that helps reduce redness in cases of moderate to severe erythema ;

• For severe forms (papulopustular), the dermatologist prescribes the doxycycline (an antibiotic) for 3 months in conjunction with a local treatment ;

  Note : Generally, the combination of oral antibiotics and topical treatment is most often prescribed due to its significant effectiveness. After the initial 3 months, the topical treatment is continued to reduce the number of flare-ups.

• In rare forms of fulminant rosacea, it is necessary to combine a corticosteroid therapy through general administration with isotretinoin ;

• For ocular forms, a consultation with an ophthalmologist is necessary. The doxycycline is the standard treatment but other local antibiotics can be used in corneal complications (fusidic acid, tetracycline etc).

Beyond pharmaceutical treatments, there are physical treatments such as the laser (the KTP laser, pulsed dye lasers, and the Nd Yag laser). The laser helps to reduce redness and visible telangiectasias associated with rosacea. It is particularly recommended for rosacea. It appears that the laser may help to reduce the recurrence of the disease.

• NAVARINI A.A. & al, Swiss S1 guideline for the treatment of rosacea (2017)