The potential role of microorganisms in the development of rosacea

Abstract

SummaryRosacea is a chronic cutaneous disorder characterized by centrofacial persisting erythema, telangiectases, papules, pustules, edema, phymas and ocular involvement. Despite being one of the most common skin disorders, its pathogenesis remains unclear and controversial. Although the disease triggering factors are well recognized, the underlying causes of rosacea have not yet been identified. Several different postulates about its pathogenesis can be found in the medical literature. Abnormalities of the pilosebaceous unit, as well as genetic, vascular, inflammatory, environmental and microbial factors have been described. The microorganisms that have been associated include Helicobacter pylori, Demodex folliculorum, Staphylococcus epidermidis, and Chlamydia pneumonia; all the studies have been inconclusive. We review currently available scientific data on the potential pathogenetic role of microorganisms in the development of rosacea.

The Study of Prevalence of Helicobacter Pylori in Patients with Acne Rosacea

“…[25][26][27][28] Based on the different studies to date Lazaridou et al later concluded that due to the high prevalence of anti-Hp antibodies in humans in conjunction with the fact that the antibiotics are effective for both disease entities, it would be very difficult to stratify the population studied against all factors that influence both rosacea and H. pylori infection. 29 Similarly the trend for an increasing prevalence of H. pylori with severity of rosacea is suggested by the study reported by Diaz et al 30 Though the study did not achieve statistical significance a suggestion of a potential positive association between the severity of rosacea and both concurrent H. pylori infection and magnitude of anti-H. pylori CagA antigen humoral immune response was observed .Our study also shows that the mean values of anti H pylori IgG antibodies follow the linear trend. The measures of association was estimated with multiple correlation (R=0.447) showing a positive linear trend and the values increases with the clinical severity of rosacea has been supported statistically (F=5.74, df=1, P=0.025).…”

Ocular rosacea: a review

“…The prevalence of H. pylori infection was found higher in patients with rosacea when compared to the general population, and its eradication has been shown to influence the clinical outcome of this disease (31,39,(44)(45)(46) . However, other studies have not found such difference (41,(47)(48)(49) . Demodex, a microscopic mite found in hair follicles and sebaceous glands, is the most common ectoparasite in humans.…”

“…Studies support its role in the activation of immune mechanisms in certain subtypes of rosacea, especially papulopustular rosacea (32) . The Demodex count was shown significantly higher in patients with facial rosacea, and a study demonstrated a strong correlation between positive serum immunoreactivity and ocular Demodex infestation in facial rosacea and lid margin inflammation (41,50,51) . Another proposed mechanism is that Demodex mites may act as vectors for other microorganisms such as Bacillus olenorium, which may be responsible for initiation of inflammatory response in rosacea, through production of antigenic proteins and stimulation of Toll-like receptor 2 (TLR2) (23,25,38,42,50) .…”

“…Microbial organisms such as Helicobacter pylori, Demodex folliculorum, Demodex brevis and Staphylococcus epidermidis have been appointed as other possible causative factors in exacerbation of the disease; however this remains a controversy (23,26,31,(38)(39)(40)(41)(42)(43) . The prevalence of H. pylori infection was found higher in patients with rosacea when compared to the general population, and its eradication has been shown to influence the clinical outcome of this disease (31,39,(44)(45)(46) .…”

Potential role of Demodex mites and bacteria in the induction of rosacea

“…disorders of the pilosebaceous unit, nutritional and chemical factors and infectious factors (Crawford et al, 2004, Yamasaki & Gallo, 2009. Over a significant period of time, there have been numerous attempts to connect the etiopathogenesis of rosacea with the presence of some micro-organisms on or within the skin (Lazaridou et al, 2011), including Demodex mites and bacteria. It is well established that there is a higher density of Demodex mites in the skin of rosacea patients than control patients but the significance of this has been disputed (Vance, 1986;Bonnar et al, 1993;Erbagci & Ozgöztaşi, 1998).…”