Rosacea: Molecular Mechanisms and Management of a Chronic Cutaneous Inflammatory Condition

Diagnosis and Treatment of Rosacea Fulminans: A Comprehensive Review

Rosacea fulminans is a rare inflammatory condition of the central face marked by the abrupt onset of erythematous coalescing papules, pustules, nodules, and draining sinuses. Due to infrequent reporting in the literature, the pathophysiology, classification, and nomenclature of this condition remain controversial. This comprehensive review evaluated a total of 135 cases of rosacea fulminans for clinical and histopathologic features and reported treatment strategies. Patients were 91% female with an average age of onset of 31.3 years. Only 19% of cases reported duration of symptoms longer than 3 months, and reports of recurrence were uncommon. A majority of patients had history of rosacea or flushing, and common triggers included hormonal shifts, emotional stress, and medications. Extrafacial or systemic involvement was rare. Though oral and topical antibiotics were frequently utilized to treat rosacea fulminans, there was a clear shift in reported treatments for rosacea fulminans following the introduction of isotretinoin use in 1987, marked by increased reliance on isotretinoin in addition to topical and systemic corticosteroids. Newer treatments were associated with superior improvement compared with antibiotic monotherapy, most notably dramatically reduced rates of scarring, though reduced rates of disease recurrence were not evident. Several patterns revealed through this review reinforce the classification of rosacea fulminans as a severe yet distinct variant of rosacea and highlight key distinguishing clinical features and treatment options for optimal management.

Rosacea Pathogenesis

Rosacea is a chronic inflammatory skin disorder that is not fully understood but involves the complex interplay of genetic factors, immune dysregulation, neurovascular dysregulation, presence of microorganisms, and environmental factors. Increased activation of the immune system occurs through multiple stimuli, including increased levels of cathelicidin and kallikrein 5, Toll-like receptor 2, matrix metalloproteinases, and mast cells within the skin. Their effects are enhanced by the presence of microorganisms and external triggers, such as UV radiation.

Molecular Mechanisms and Management of a Cutaneous Inflammatory Disorder: Psoriasis

Psoriasis is a complex chronic inflammatory cutaneous disorder. To date, robust molecular mechanisms of psoriasis have been reported. Among diverse aberrant immunopathogenetic mechanisms, the current model emphasizes the role of Th1 and the IL-23/Th17 axis, skin-resident immune cells and major signal transduction pathways involved in psoriasis. The multiple genetic risk loci for psoriasis have been rapidly revealed with the advent of a novel technology. Moreover, identifying epigenetic modifications could bridge the gap between genetic and environmental risk factors in psoriasis. This review will provide a better understanding of the pathogenesis of psoriasis by unraveling the complicated interplay among immunological abnormalities, genetic risk foci, epigenetic modification and environmental factors of psoriasis. With advances in molecular biology, diverse new targets are under investigation to manage psoriasis. The recent advances in treatment modalities for psoriasis based on targeted molecules are also discussed.

Human Skin Permeation Studies with PPARγ Agonist to Improve Its Permeability and Efficacy in Inflammatory Processes

Rosacea is the most common inflammatory skin disease. It is characterized by erythema, inflammatory papules and pustules, visible blood vessels, and telangiectasia. The current treatment has limitations and unsatisfactory results. Pioglitazone (PGZ) is an agonist of peroxisome proliferator-activated receptors (PPARs), a nuclear receptor that regulates important cellular functions, including inflammatory responses. The purpose of this study was to evaluate the permeation of PGZ with a selection of penetration enhancers and to analyze its effectiveness for treating rosacea. The high-performance liquid chromatography (HPLC) method was validated for the quantitative determination of PGZ. Ex vivo permeation experiments were realized in Franz diffusion cells using human skin, in which PGZ with different penetration enhancers were assayed. The results showed that the limonene was the most effective penetration enhancer that promotes the permeation of PGZ through the skin. The cytotoxicity studies and the Draize test detected cell viability and the absence of skin irritation, respectively. The determination of the skin color using a skin colorimetric probe and the results of histopathological studies confirmed the ability of PGZ-limonene to reduce erythema and vasodilation. This study suggests new pharmacological indications of PGZ and its possible application in the treatment of skin diseases, namely rosacea.

Rosacea and its association with enteral microbiota in Korean females

Rosacea is a chronic inflammatory dermatosis affecting the face and eyes. An association between systemic comorbidities and rosacea has been reported, but the link to enteral microbiota is uncertain. We aimed to investigate the link between rosacea and enteral microbiota. A cross-sectional study was performed in a sample of Korean women who participated in a health check-up programme at the Kangbuk Samsung Hospital Health Screening Center between 23 June 2014 and 5 September 2014. The gut microbiome was evaluated by 16S rRNA gene and metagenome sequence analyses. A total of 12 rosacea patients and 251 controls were enrolled. We identified links between rosacea and several changes in gut microbiota: reduced abundance of Peptococcaceae family unknown genus, Methanobrevibacter (genus), Slackia (genus), Coprobacillus (genus), Citrobacter (genus), and Desulfovibrio (genus), and increased abundance of Acidaminococcus (genus), Megasphaera (genus), and Lactobacillales order unknown family unknown genus. A link between rosacea and enteral microbiota was observed in this metagenomic study. A large and elaborate study is needed to confirm these findings and to elucidate the mechanisms involved.

Long-term management of distinct facial flushing and persistent erythema of rosacea by treatment with carvedilol

BACKGROUND

The treatment of persistent erythema and flushing episodes in patients with rosacea remains a clinical challenge. A possible therapeutic option could be the use of antihypertensive drugs.

OBJECTIVES

We therefore evaluated the effect of the non-selective β-blocker carvedilol in five Caucasian patients.

METHODS

In a monocentric retrospective case study, the patients were treated with carvedilol titrated up to 12.5 mg twice a day over at least six months. Patients self assessment (PSA), clinicians erythema assessment (CEA), and the patients levels of embarrassment and satisfaction were performed by questionaires.

RESULTS

The CEA grade description as well as the PSA grade description decreased remarkably in all five patients. Furthermore, all patients reported to have a major improvement of their level of satisfaction and no feelings of embarrassment anymore.

CONCLUSIONS

These findings demonstrate that facial flushing and persistent erythema can be effectively treated by carvedilol long-term with a fast onset of improvement in a dose well tolerated.