Acne rosacea is a chronic disorder of unknown cause that affects the central face. At least 13 million people are affected by this noncurable disorder. It is characterized by two clinical components: a vascular change consisting of intermittent or persistent erythema and flushing and an acneiform eruption with papules, pustules, cysts, and sebaceous hyperplasia. There is no correlation between the sebum excretion rate and the severity of Acne rosacea. Lesional blood flow as measured by laser Doppler is three to four times that of controls. Onset is most often between the ages of 30 and 50; pediatric cases have also been reported. Although women are affected three times as frequently as men, the disease may become more severe in men. Acne rosacea is much more common in light-skinned, fair-complexioned individuals but may also occur in darker skin types. It is estimated that 10% of individuals in Sweden have Acne rosacea.
There is speculation that a defect in the trigeminal afferent nerve pathway contributes to a predisposition to facial flushing. Over time, after repeated bouts of flushing, the vessels become ectatic and there is permanent vasodilatation. Hot liquids are thought to promote erythema and flushing when they heat up the tissues of the oral mucosa, leading to a countercurrent heat exchange with the carotid artery. A further signal from the carotid body is then relayed to the hypothalamus (the body's thermostat), which signals the body to dissipate heat through flushing and vasodilatation because of the perceived increase in core body temperature.
Helicobacter pylori, a microaerophilic gram-negative bacteria implicated in gastric ulcer disease, has been theorized to be the inciting organism in Acne rosacea on the basis of an increased incidence of dyspepsia in this population and the responsiveness of Acne rosacea to metronidazole. Fifty percent of the world's population and 25% of the US population may have antibodies to this organism. Colonization is associated with increased levels of serum gastrin, which can cause flushing. Also, H. pylori infection can increase levels of histamine, prostaglandins, leukotrienes, and various other cytokines. Therapy to eradicate this organism usually consists of a combination of oral metronidazole, amoxicillin, and omeprazole. Conflicting studies regarding this association with Acne rosacea have recently been in the literature. In general, it is felt that strong support for a link between H. pylori infection and Acne rosacea is lacking. Large case control studies would be needed to prove this association because of the high baseline incidence of this exposure.
Infection with Demodex mites is common, with infection approaching 100% in sensitive tests of healthy adults. Some have hypothesized that infection with Demodex is a cause of Acne rosacea. There is controversy within the literature whether this is the case. In one study, there was a link between higher mite counts and papulopustular but not erythematotelangiectatic Acne rosacea. It is unclear whether Demodex is pathologic or just normal skin flora.
what is Rosacea
Rosacea is a common chronic inflammatory disorder of the hair follicles, sebaceous glands and vasculature of the face. The role of Demodex mite in the pathogenesis of Rosacea is controversial.
Rosacea sufferers have recurrent flushing, exacerbated by heat (shower, hot drinks), spicy foods, sunlight, cold, alcohol, and stress. They have sensitive skin, and may complain of dry and gritty eyes.
The peak incidence of Rosacea is 30—50 yr; Females being more affected than Males.
Rosacea sufferers may develop erythema, telangiectases, papules, and pustules of central face; there are no comedones in contrast to acne. Sebaceous hyperplasia, seborrheic dermatitis and facial lymphedema are also more common.
There are 4 Major Subtypes of Rosacea:
Erythematotelangiectatic, papulopustular, ocular, and phymatous.
Chronic inflammation may progress to rhinophyma (enlarged nose; in males). Ocular involvement is also common (e.g., gritty, conjunctival injection, styes, photophobia).
Investigations include clinical diagnosis; uncommonly, skin biopsy is indicated to rule out lupus or sarcoidosis.
Similar conditions that needs to be differentiated from Rosacea are: Acne, lupus erythematosus, perioral dermatitis, sarcoidosis, seborrheic dermatitis.
Treatment of Rosacea is based on severity and subtype.
Lifestyle modification:
Avoid triggers; sun protection and avoidance; facial massage for lymphedema.
Topical antibiotics:
Metronidazole 0.75% gel or 1% cream bid.
Sodium sulfacetamide lotion 10% bid.
Oral antibiotics (moderate to severe cases with inflammatory papulopustular component):
Tetracycline 500 mg po bid
Minocycline 100 mg po od—bid.
Doxycycline 20 mg po bid (subantimicrobial dose therapy) or 100 mg po qd–bid.
Isotretinoin (low dose); less commonly, topical retinoids may be used.
Laser therapy (e.g., PDL, IPL) for telangiectases and ablative laser (e.g., CO2) for rhinophyma.
Camouflage makeup (e.g., Dermablend, Covermark) for erythema.
Ophthalmologist to assess for ocular Rosacea (blepharitis, conjunctivitis, episcleritis).
