Rosacea is a common inflammatory facial skin disorder classically marked by flushing, facial erythema, inflammatory papules and pustules, and telangiectasias. It typically presents in adults, with prevalence reported as 1 to greater than 20%, with a female predominance; whether rosacea exists in children and adolescents is debated in the literature. Individuals in all racial and ethnic groups may be affected by rosacea. Patients often report a strong familial history of rosacea and individuals of Celtic background are commonly affected.
The classification of rosacea is largely based on the predominant cutaneous morphologic features (erythemato-telangiectactic, papulopustular, phymatous and ocular). Rare variants, such as granulomatous, must be distinguished from other inflammatory conditions such as sarcoidosis. Treatment is largely targeted to the key skin characteristics. However, rosacea is a condition of many faces: it is important to recognize that facial erythema is present in almost all types of rosacea, and many subtypes of rosacea will overlap within an individual patient.
Rosacea typically affects the central face: cheeks, chin, forehead and nose. In rare cases, it will also present on the ears. The hallmark of rosacea is persistent facial erythema, present in all rosacea subtypes. Patients describe intermittent facial flushing, which results in persistent facial erythema, sometimes followed by development of papulopustular lesions, and rarely, phymatous changes. As such, the most common subtype is the erythemato-telangiectatic (ET) type, marked by persistent facial erythema, telangiectasias, and intermittent flushing. These patients often report highly sensitive, cosmetically intolerant skin which likely stems from an abnormal skin barrier. The papulopustular form of rosacea describes patients with persistent facial erythema and transient papules and pustules, which is sometimes confused for acne vulgaris. Key clinical features that distinguish this rosacea subtype from acne vulgaris are the presence of flushing, absence of comedones, and commonly, the absence of nodulocystic lesions and scarring.
Phymatous rosacea is the rarest subtype, seen almost exclusively in males. It is characterized by highly glabrous skin, sebaceous hyperplasia, and firm induration of the skin (resulting from fibrosis) that can be cosmetically disfiguring in appearance. The nose is the most common site of phymatous rosacea, termed rhinophyma, but the ears (otophyma), chin (gnathophyma), forehead (metophyma), and eyelids (blepharophyma) can also be affected. Ocular rosacea is estimated to affect almost half of patients with cutaneous rosacea. Ocular symptoms of rosacea include blepharitis, conjunctivitis or keratitis and patients may complain about bloodshot eyes, foreign body sensation, excessive tearing, light sensitivity and blurred vision. It is important for clinicians to recognize this ocular form of rosacea, as it – left untreated – can result in devastating visual impairment primarily due to chronic keratitis.
Patients with rosacea commonly report flushing as a preceding symptom and identify clear triggers of flushing: sun exposure, stress, hot and cold weather, temperature changes, physical exercise, hot beverages, alcohol consumption, and spicy foods. Rarely, medications (such as niacin used for cholesterol or vasodilators) are a cause of flushing that exacerbates a flare of rosacea.
The etiology of rosacea is unknown. Investigators hypothesize that rosacea stems from a constellation of abnormalities of skin, including of small cutaneous blood vessels and nerves, the surrounding connective tissue and an abnormal inflammatory response. Chronic inflammation is the hallmark of rosacea, underlying many of the clinical signs and symptoms of the disease. Recent studies have highlighted the role of key innate immune factors, including antimicrobial peptides (cathelicidin, LL-37, beta-defensins), serine protease enzymes, and Toll-like Receptors (TLRs) in mediating inflammation. The articulation between the cutaneous nervous system and vasculature, largely through key neuropeptides, may also promote inflammation and may also underlie the complaint of stinging or sensitivity of skin that is frequently reported by patients with rosacea. The contribution of the commensal cutaneous mite, Demodex folliculorum, is speculated, as patients with rosacea have been characterized to have numerous mites and pathways have been identified that link these mites back to key immunologic mediators known to play an important role in pathogenesis of rosacea. Demodex mites may play a particularly important role in underlying the rare papulovesicular variant of rosacea, which is best treated by therapies that target this cutaneous mite. The efficacy of a newly approved agent, topical ivermectin 1% cream, whose dual mechanisms include anti parasitic activity, suggest the importance of this cutaneous mite in the pathophysiology of disease.
There is currently no definitive cure for rosacea. The most important principle of rosacea therapy is that it is a chronic condition that must be managed over time. Despite the best treatment plans, patients commonly relapse and remit. Still, avoidance of triggers is the foremost recommendation, and thus patients with rosacea must be counseled carefully to their pivotal role in managing their own disease through trigger avoidance. Treatment is discussed in Therapeutic Strategies. Most patients with rosacea will require some type of additional treatment on a long-term basis for maintenance of their disease. For the most common feature of rosacea, lasers and intense pulsed light devices have been used for telangiectasia and redness with variable efficacy. Topical brimonidine gel (Mirvaso) is a recently approved medication indicated for the treatment of facial erythema in rosacea, representing a novel approach to the treatment of ET rosacea.
Patient education is a key principle in the management of rosacea and most experts incorporate advice on potential trigger factors and on use of gentle, non-irritating skin care products. Facial moisturizers should be recommended to hydrate the skin and restore skin barrier; restoration of a normal skin barrier may in turn alleviate symptoms of cosmetic intolerance and also mitigate skin inflammation. Protection from ultraviolet light is paramount, for which physical coverage and sunscreens are first-line (to reflect light and heat that can exacerbate flushing). Camouflage techniques, especially with green tint-containing make-up, can be employed to mask facial redness.
Though rosacea primarily affects the face and eyes, it can cause significant detriment on quality of life due to both physical discomfort and impact on self-esteem, discussed in the following section entitled Living with rosacea: Impact on quality of life. Patients with rosacea may suffer from the common misconceptions and social stigmas about the disease, including being viewed as heavy users of alcohol. Surveys indicate that people have a negative impression of patients with rosacea.
There are many available current therapies to treat the different hallmarks of rosacea; some key therapies are approved for the indication of rosacea whereas many others are off-label uses with variable efficacy. More studies are clearly needed to provide the evidence for the most effective management strategies for this common, chronic skin condition. Because overlap features of the rosacea subtypes often exist, it is imperative for the clinician to correctly identify subtype features and target them with available treatments. Patient education on skin care, photoprotection, and trigger avoidance are also essential. Clinicians should also be aware of the significant impact of this disease on patient quality of life, and provide support as part of a holistic, long-term plan of care.