Positive correlation between serum immunoreactivity toDemodex-associatedBacillusproteins and erythematotelangiectatic rosacea

Rosacea in East Asian populations: Clinical manifestations and pathophysiological perspectives for accurate diagnosis

Rosacea is a chronic inflammatory disorder primarily affecting the facial skin, prominently involving the cheeks, nose, chin, forehead, and periorbital area. Cutaneous manifestations encompass persistent facial erythema, phymas, papules, pustules, telangiectasia, and flushing. The pathogenesis of rosacea is associated with various exacerbating or triggering factors, including microbial infestation, temperature fluctuations, sunlight exposure, physical exertion, emotional stress, consumption of hot beverages and spicy foods, and exposure to airborne pollen. These environmental factors interact with genetic predispositions in the development of rosacea. The roles of the lipophilic microbiome, ultraviolet radiation, nociceptive responses, and vascular alterations have been proposed as significant factors in the pathogenesis. These insights contribute to understanding the anatomical specificity of facial involvement and the progressive nature of rosacea. East Asian skin, predominantly classified as Fitzpatrick skin phototypes III to IV, is characterized by relatively diminished skin barrier function and increased sensitivity to irritants. Airborne pollen exposure may particularly act as a trigger in East Asian individuals, possibly mediated through toll-like receptors. The lack of specificity in objective clinical and histopathological findings leads to diagnostic challenges for individuals with colored skin, including East Asians, particularly when erythema is the sole objective manifestation. An alternative diagnostic scheme may thus be necessary. A diagnostic approach emphasizing vascular manifestations and nociceptive symptoms potentially holds promise for individuals with darker skin tones. More research focusing on potential variations in skin physiology across different racial groups is essential to establish more effective diagnostic schemes applicable to both dark and light skin colors.

Clinical spectrum in microbiologically proven Demodex blepharokeratoconjunctivitis: An observational study

PURPOSE

To study the demographic, clinical, and microbiological profile of Demodex-related blepharokeratoconjunctivitis (BKC) at a tertiary eye care hospital.

METHODS

This retrospective observational study was conducted from January 2016 to September 2022. It included 83 patients with microbiologically proven Demodex BKC who presented to the cornea department of our tertiary care eye center. The clinical, microbiological, and demographic data of the 83 cases were analyzed.

RESULTS

Of the 83 cases, 57 (68.67%) were younger than 40 years, and 25 (30.12%) were below 20. Most patients presented with a good visual acuity of 20/40 or better (93 eyes; 84.55%). The disease was unilateral in 55 patients and bilateral in 28. Cylindrical dandruff was the predominant presentation noted in 61 eyes (54.95%), followed by corneal scarring in 47 eyes (42.34%) and corneal vascularization in 40 eyes (36.04%). On light microscopy, 87.95% of the positive samples were identified as Demodex folliculorum , 7.23% as Demodex brevis , and 6.02% remained unidentified. Tea tree oil and lid scrubs eradicated the disease in most patients clinically (75/83, 90.36%).

CONCLUSION

The spectrum of BKC includes both lid signs and corneal involvement. It can be a cause of recurrent BKC and detection of the mite by microscopic evaluation of the lashes can confirm the diagnosis. In most cases, the tea tree oil can effectively manage this condition. However, low doses of topical steroids are needed to control the inflammation in patients with corneal involvement.

Beyond the Surface: Understanding Demodex and Its Link to Blepharitis and Facial Dermatoses

Demodex represents the most frequent ectoparasite found in humans. Although Demodex mites are considered commensals of human pilosebaceous units, an abnormally high mite density can cause several ocular and cutaneous symptoms and signs, sometimes to a severe degree. Both Demodex spp. (folliculorum and brevis) play a significant part in eye pathology and facial dermatoses. These mites have been related to blepharitis, ocular rosacea, meibomian gland dysfunction and various skin diseases, including rosacea, demodicosis and seborrheic dermatitis. Understanding the importance of Demodex in both eye and skin conditions is crucial for accurate diagnosis and appropriate management strategies, which may involve targeted treatments to control the mite population and reduce associated symptoms.

Hematological parameters as diagnostic biomarkers for patients with rosacea

Rosacea is a chronic inflammatory skin disease. Systemic inflammation plays a vital role in the pathogenesis of rosacea. Many studies have reported hematological parameters as biomarkers for diseases with inflammatory processes. However, the diagnostic value of hematological parameters in rosacea remains a puzzle. This study involved 462 patients with rosacea, including erythematotelangiectatic rosacea (ETR, n = 179), papulopustular rosacea (PPR, n = 250), and phymatous rosacea (PhR, n = 33), and 924 healthy control subjects. Demographic, clinical, and laboratory information was collected and compared between rosacea subtypes. The hematological parameters of the patients and the healthy controls were compared retrospectively. The platelet volume (MPV) and platelet crit (PCT) were significantly upregulated, and the lower red cell distribution width (RDW) was significantly downregulated in rosacea compared to healthy controls, and they were identified as the diagnostic biomarkers for rosacea with area under the curve values of 0.828, 0.742, and 0.787, respectively. Comparing the hematological parameters among the three rosacea subtypes, we found that platelet-to-lymphocyte ratio and platelet-to-neutrophil ratio values in the ETR group were significantly higher than those in the PPR and PhR groups. The correlation between hematological parameters and clinical scores showed that RDW was negatively correlated with the Clinician Erythema Assessment score. However, there was no significant correlation between the Investigator Global Assessment score and hematological parameters. In conclusion, PCT, MPV, and RDW have diagnostic value for rosacea, and RDW is correlated with the severity of rosacea erythema, implying the potential applications of PCT, MPV, and RDW in the diagnosis and monitoring of rosacea.

The Skin Microbiome and its Significance for Dermatologists

The skin is a physical and immunological barrier to the external environment. Its large surface area is colonized by diverse communities of microorganisms, including bacteria, viruses, fungi, and Demodex species mites. These microorganisms and their genetic material together create the skin microbiome. Physiologic and anatomic properties of skin sites create biogeographical habitats (dry, moist, and sebaceous) where distinct microbiota communities reside. Although, in general, the composition of these habitats is maintained from person to person, the skin microbiome of an individual also has unique microbial features. Dysbiosis occurs when the normal abundance, composition, or location of the microbiota is changed, most notably there is a decrease in flora diversity. Certain skin diseases, including atopic dermatitis, rosacea, and psoriasis are associated with cutaneous dysbiosis, and even disruption of the gut microbiota. Studies have shown that current treatments for these dermatologic conditions can alter/stabilize the skin microbiome, and there is emerging research detailing the impact of prebiotics, probiotics, and postbiotics on these conditions. Although clinical guidelines do not currently exist, clinical studies support the safety and possible benefits of using topical prebiotics and postbiotics and oral probiotics for a variety of skin conditions. Until such guidelines exist, utilizing carefully designed clinical studies to inform clinical practice is recommended.

Microbiome: Role in Inflammatory Skin Diseases

As the body's largest organ, the skin harbors a highly diverse microbiota, playing a crucial role in resisting foreign pathogens, nurturing the immune system, and metabolizing natural products. The dysregulation of human skin microbiota is implicated in immune dysregulation and inflammatory responses. This review delineates the microbial alterations and immune dysregulation features in common Inflammatory Skin Diseases (ISDs) such as psoriasis, rosacea, atopic dermatitis(AD), seborrheic dermatitis(SD), diaper dermatitis(DD), and Malassezia folliculitis(MF).The skin microbiota, a complex and evolving community, undergoes changes in composition and function that can compromise the skin microbial barrier. These alterations induce water loss and abnormal lipid metabolism, contributing to the onset of ISDs. Additionally, microorganisms release toxins, like Staphylococcus aureus secreted α toxins and proteases, which may dissolve the stratum corneum, impairing skin barrier function and allowing entry into the bloodstream. Microbes entering the bloodstream activate molecular signals, leading to immune disorders and subsequent skin inflammatory responses. For instance, Malassezia stimulates dendritic cells(DCs) to release IL-12 and IL-23, differentiating into a Th17 cell population and producing proinflammatory mediators such as IL-17, IL-22, TNF-α, and IFN-α.This review offers new insights into the role of the human skin microbiota in ISDs, paving the way for future skin microbiome-specific targeted therapies.

Rosacea, microbiome and probiotics: the gut-skin axis

Rosacea is an inflammatory skin disease involving diverse symptoms with a variable clinical progress which can severely impact the patient's quality of life as well as their mental health. The pathophysiological model of rosacea involves an unbalanced immune system predisposed to excessive inflammation, in addition to vascular and nervous alterations, being certain cutaneous microorganisms' triggers of the symptoms onset. The gut-skin axis explains a bidirectional interaction between skin and gut microbiota in some inflammatory skin diseases such as atopic dermatitis, psoriasis, or rosacea. The introduction and consolidation of the next-generation sequencing in recent years has provided unprecedented information about the microbiome. However, the characterization of the gut and skin microbiota and the impact of the gut-skin axis in patients with rosacea has been little explored, in contrast to other inflammatory skin diseases such as atopic dermatitis or psoriasis. Furthermore, the clinical evolution of patients with rosacea is not always adequate and it is common for them to present a sustained symptomatology with frequent flare-ups. In this context, probiotic supplementation could improve the clinical evolution of these patients as happens in other pathologies. Through this review we aim to establish and compile the basics and directions of current knowledge to understand the mechanisms by which the microbiome influences the pathogenesis of rosacea, and how modulation of the skin and gut microbiota could benefit these patients.

Demodex Species and Culturable Microorganism Co-Infestations in Patients with Blepharitis

We aimed to determine the prevalence of Demodex spp. and bacterial infection in patients with blepharitis and also to investigate the relationship between culturable microorganisms and Demodex spp. in this study. The study included patients diagnosed with blepharitis (n = 128) and volunteers without ocular problems (n = 113). Eyelash sampling was performed by epilating eight lashes, which were then tested for Demodex spp. using a light microscope. The examination consisted of assessing the patient's vision with and without ocular correction and tonus in both eyes and a careful examination of the anterior segment of both eyes. Bacterial identification was performed based on morphological, physiological, and biochemical methods. The prevalence of Demodex spp. was 8.0% in patients from the control group and all patients with blepharitis. Isolated forms of Demodex spp. were detected in all infested patients in the control group and in 58% of patients with blepharitis. A total of 35% of patients with blepharitis had from three to nine forms of Demodex spp., and 7% of patients with blepharitis had more than 10 mites in every field of vision. We found a statistically significant relationship between Demodex spp. infestation and the occurrence of eye dryness and sensations of burning and tearing, redness of the conjunctiva, feeling of a foreign body, loss of eyelashes, Meibomian gland dysfunction, and cylindrical dandruff. There were statistically significant relationships between Demodex sp. infestation and the presence of hyperopia, Meibomian cysts, chronic eyelid inflammation, and the use of eyeglasses. There was also a statistically significant relationship between the occurrence of Demodex spp. and seborrheic dermatitis and diabetes mellitus. Culturable microorganisms of the ocular surface were found in 8.7% of participants who were uninfested and in all patients infested with D. folliculorum. We isolated Staphylococcus aureus, Acinetobacter baumannii, Streptococcus pneumoniae, Klebsiella oxytoca, and Bacillus spp. from the conjunctival sac only in patients infested with D. folliculorum. This indicates an increased probability of colonization by pathogenic bacteria in patients with demodicosis. Therefore, patients infested with D. folliculorum should undergo a microbiological examination of conjunctival swabs.

Novel treatment of chalazion using light-guided-tip intense pulsed light

We assessed the effectiveness of light-guided-tip intense pulsed light (IPL) with meibomian gland expression (MGX) in chalazion treatment. Ninety-five eyes with chalazion received a light-guided-tip IPL-MGX treatment (IPL-MGX group), and another 95 eyes with chalazion received incision with curettage treatment (Control group). Prior to IPL or incision, as well as 1 month after the final treatment, data were gathered pertaining to the lesion location and size, hyperemia, lesions regression or recurrence, and a comprehensive ophthalmic examination. The total size of the chalazia in the IPL-MGX group was significantly reduced after the final treatment, with an average resolution rate of 70.5%, which is comparable to excision surgery. A significant decrease in chalazion recurrence rate was apparent after treatment in the IPL-MGX group compared with control. Moreover, the IPL-MGX demonstrated significant advancements throughout noninvasive tear film breakup time (NIBUT) as well as meibum grade in comparison to baseline and those in the the Control group. The use of IPL-MGX was found to be an efficient therapy for reducing the size and recurring frequency of chalazia, as well as for improving the meibomian gland function. It may be considered as a first-line treatment for cases of primary or recurrent chalazia with inflammation.

Evolving approaches to profiling the microbiome in skin disease

Despite its harsh and dry environment, human skin is home to diverse microbes, including bacteria, fungi, viruses, and microscopic mites. These microbes form communities that may exist at the skin surface, deeper skin layers, and within microhabitats such as the hair follicle and sweat glands, allowing complex interactions with the host immune system. Imbalances in the skin microbiome, known as dysbiosis, have been linked to various inflammatory skin disorders, including atopic dermatitis, acne, and psoriasis. The roles of abundant commensal bacteria belonging to Staphylococcus and Cutibacterium taxa and the fungi Malassezia, where particular species or strains can benefit the host or cause disease, are increasingly appreciated in skin disorders. Furthermore, recent research suggests that the interactions between microorganisms and the host's immune system on the skin can have distant and systemic effects on the body, such as on the gut and brain, known as the "skin-gut" or "skin-brain" axes. Studies on the microbiome in skin disease have typically relied on 16S rRNA gene sequencing methods, which cannot provide accurate information about species or strains of microorganisms on the skin. However, advancing technologies, including metagenomics and other functional 'omic' approaches, have great potential to provide more comprehensive and detailed information about the skin microbiome in health and disease. Additionally, inter-species and multi-kingdom interactions can cause cascading shifts towards dysbiosis and are crucial but yet-to-be-explored aspects of many skin disorders. Better understanding these complex dynamics will require meta-omic studies complemented with experiments and clinical trials to confirm function. Evolving how we profile the skin microbiome alongside technological advances is essential to exploring such relationships. This review presents the current and emerging methods and their findings for profiling skin microbes to advance our understanding of the microbiome in skin disease.

Skincare in Rosacea from the Cosmetologist's Perspective: A Narrative Review

Rosacea is a common skin disease that affects about 5% of the general population. Its symptoms include telangiectasia, persistent erythema, burning/stinging sensation, dry skin sensation, and pruritus. It is characterized by a chronic course with frequent exacerbation. It often coexists with anxiety and depression, reducing the quality of life of affected patients. The etiopathogenesis of rosacea is complex and not fully elucidated; hence, there is no causative effective treatment. In this review, we highlight the role of a cosmetologist in the treatment of rosacea and the maintenance of remission. As part of medical treatment, patients are advised to introduce lifestyle changes and use proper skin care; a cosmetologist can help educate patients affected with rosacea, create effective home care programs for skin care, and support them with treatments in beauty salons. Proper skin care is essential, including the use of dermocosmetics, cleansing of the skin, and frequent visits to beauty salons for tailored apparatus procedures. A cosmetologist is more accessible to patients and can help implement healthy daily habits, including skin care and eating habits, as well as support and mediate good communication between the patient and the patient's treating physician, thereby improving compliance and ensuring long-term satisfactory outcomes.

Relationships of Serum Homocysteine, Vitamin B12, and Folic Acid Levels with Papulopustular Rosacea Severity: A Case-Control Study

Background

Rosacea is a chronic inflammatory skin disease with a multifactorial etiology. Recently, associations between serum homocysteine (Hcy) levels and inflammatory skin diseases, such as psoriasis and hidradenitis suppurativa, have been reported. However, no study has explored the levels of serum Hcy, folic acid, and vitamin B₁₂ in patients with rosacea.

Objective

To investigate serum Hcy, vitamin B₁₂, and folic acid levels in patients with papulopustular rosacea (PPR), we characterized the association of these levels with PPR severity.

Methods

This case-control study included 138 PPR patients and 58 healthy controls. The serum levels of Hcy, vitamin B₁₂, and folic acid were measured. A correlation was assessed between disease severity and serum levels of Hcy, vitamin B₁₂, and folic acid.

Results

Serum vitamin B₁₂ and folic acid levels were significantly lower in PPR patients than in the healthy controls (p = 0.011 and p = 0.0173, respectively). Although serum Hcy levels did not significantly differ between PPR patients and healthy controls, PPR severity was positively correlated with serum Hcy levels (p < 0.001).

Conclusions

Our results suggest a possible association between hyperhomocysteinemia and vitamin B₁₂ deficiency in patients with PPR.

Demodex: the worst enemies are the ones that used to be friends

Demodex mites are common ectoparasites of the human pilosebaceous units. Most adults are infested with Demodex mites without clinical symptoms. Demodex mite will only become a pathogenic organism when there is an abnormal increase in the number of Demodex mite density. This situation happens when the equilibrium between Demodex mites, skin microenvironment and human immunity system changes. Demodex infestation can cause multiple skin disorders, which are grouped under the term demodicosis or demodicidosis. Clinical manifestations of demodicosis can mimic other known skin diseases such as folliculitis, rosacea, perioral dermatitis, which is why it is often misdiagnosed. Diagnosis criteria consists of relevant correlation of suspected clinical skin lesions, confirmed by the presence of abnormal proliferation of Demodex mites and by clinical cure after acaricidal treatment together with normalization of Demodex mite density. Dermatologists should be aware that demodicosis is not an uncommon skin disease, and there are still many unknowns about it that should be researched further.

Demodex folliculorum (Trombidiformes: Demodicidae) and Demodex brevis Prevalence in an Extreme Environment of Chile

The prevalence of mites of the genus Demodex and their associations with host age, gender, workplace, and comorbid skin and ocular conditions were studied in participants in Antofagasta, Chile, which is in a region with an extreme environment. We examined 680 participants aged 18-88 yr using standardized surface skin biopsies. Among them, Demodex had a prevalence of 13.5 % (95% confidence interval, 10.88-16.17). A slightly higher prevalence was observed in males (51.1%; 95% confidence interval, 40.9-61.3; nonsignificant) and participants in the 69-88 yr age group (50.0%; 95% confidence interval, 23.8-76.2; P < 0.05). Regarding the species involved, Demodex folliculorum was found in 89.1% (CI 82.7-95.5) of cases, while D. brevis was found in the remaining 10.9% of cases. A higher prevalence (25.0% CI 16.1-33.91) was observed in participants who worked indoors in generally enclosed and dust-rich environments (such as theaters, libraries, and administrative offices). There was also a strong association between Demodex prevalence and conjunctival hyperemia, with 35.9% (95% confidence interval, 9.1-35; OR 17.9) of the Demodex positive participants having this pathology compared to 10.3% of the noninfested participants. In summary, the prevalence of Demodex in Antofagasta, Chile (13.5%) was toward the lower end of the range reported among other regions around the world. Environmental factors such as exposure to the sun (including ultraviolet rays) or environmental pollution may affect the mites. In addition, Demodex genetics (related to virulence) and the ocular or skin microbiota may positively or negatively influence infestation and pathology.

Alarmins/stressorins and immune dysregulation in intractable skin disorders

Unlike other barrier epithelia of internal organs, the stratified squamous epithelium of the skin is always exposed to the external environment. However, the robust barrier structure and function of the skin are highly resistant against external insults so as to not easily allow foreign invasions. Upon sensing danger signals, the innate immunity system is promptly activated. This process is mediated by alarmins, which are released passively from damaged cells. Nuclear alarmins or stressorins are actively released from intact cells in response to various cellular stresses. Alarmins/stressorins are deeply involved in the disease processes of chronic skin disorders of an unknown cause, such as rosacea, psoriasis, and atopic dermatitis. Furthermore, alarmins/stressorins are also induced in the congenital skin disorders of ichthyosis and keratoderma due to defective keratinization. Studies on alarmin activation and its downstream pathways may help develop novel therapeutic agents for intractable skin disorders.

Efficacy of Intense Pulsed Light Treatment for Moderate to Severe Acute Blepharitis or Blepharoconjunctivitis: A Retrospective Case Series

Objectives

We aimed to evaluate the efficacy of periocular intense pulsed light (IPL) therapy in the treatment of moderate to severe acute blepharitis or blepharoconjunctivitis.

Materials and Methods

This was a retrospective study performed in one institution. Eleven patients who received bilateral periocular IPL therapy using an IPL device (E>Eye, ESwin, Paris, France) were retrospectively evaluated. The following findings obtained at baseline and 10 weeks after the treatment were recorded: slit-lamp examinations; symptom scores of the Compression of the Eyelid (COTE) grading system and Ocular Surface Disease Index (OSDI); ocular surface staining with Oxford grading scale (OXFORD) scores; lipid layer thickness (LLT); and non-invasive tear meniscus test (TMH), non-invasive break up time measurement (NIBUT), and meibography performed by using I.C.P. Ocular Surface Analyzer (SBM System, Turin, Italy).

Results

Significant improvements in OSDI symptom scores (p<0.0001), LLT (p<0.0001), and meibography (p<0.0001) were obtained at 10 weeks after bilateral periocular IPL therapy. COTE and ocular surface staining scores decreased by 59.72% and 57.14% respectively, while NIBUT and TMH increased by 47.34% and 22.16%, respectively. In parallel to the improvement in OSDI, LLT, and meibography, findings of acute blepharitis or blepharoconjunctivitis improved in slit-lamp examination. There were no adverse effects.

Conclusion

Serial IPL therapy improves the clinical signs and symptoms of moderate to severe acute blepharitis or blepharoconjunctivitis, meibomian gland morphology, and secretion quality.

Gut-Skin Axis: Current Knowledge of the Interrelationship between Microbial Dysbiosis and Skin Conditions

The microbiome plays an important role in a wide variety of skin disorders. Not only is the skin microbiome altered, but also surprisingly many skin diseases are accompanied by an altered gut microbiome. The microbiome is a key regulator for the immune system, as it aims to maintain homeostasis by communicating with tissues and organs in a bidirectional manner. Hence, dysbiosis in the skin and/or gut microbiome is associated with an altered immune response, promoting the development of skin diseases, such as atopic dermatitis, psoriasis, acne vulgaris, dandruff, and even skin cancer. Here, we focus on the associations between the microbiome, diet, metabolites, and immune responses in skin pathologies. This review describes an exhaustive list of common skin conditions with associated dysbiosis in the skin microbiome as well as the current body of evidence on gut microbiome dysbiosis, dietary links, and their interplay with skin conditions. An enhanced understanding of the local skin and gut microbiome including the underlying mechanisms is necessary to shed light on the microbial involvement in human skin diseases and to develop new therapeutic approaches.

Rosacea and the Microbiome: A Systematic Review

Rosacea, a chronic inflammatory skin disease characterized by recurrent episodes of facial flushing, erythema, pustules, and telangiectasia, largely affects fair-skinned women over 30 years of age. Although a long-recognized entity, the exact pathophysiology of this disease is still debated. Current theories highlight the role of the cutaneous microbiome and its associated inflammatory effects in rosacea's pathogenesis. However, microbiological reverberations are not limited to the skin, as recent studies have described the potential cutaneous effects of alterations in the gastrointestinal (GI) microbiome. Associations with additional GI pathologies, including small intestinal bacterial overgrowth (SIBO), irritable bowel syndrome (IBS), and inflammatory bowel disease (IBD), have been investigated, as well as Helicobacter pylori infection. In an attempt to better understand and characterize these relationships, as well as current treatment options, we conducted a systematic review of the literature in PubMed, Cochrane, and Embase from their inception to August 6, 2020. We have synthesized the literature findings within three sections of this manuscript: the cutaneous microbiome, the gut microbiome, and therapeutic strategies. Future studies should focus on specific mechanisms linking GI pathology with rosacea manifestations and the role of enteral drugs in mitigating cutaneous symptoms.

Interactions between immune system and the microbiome of skin, blood and gut in pathogenesis of rosacea

The increasingly wide use of next-generation sequencing technologies has revolutionised our knowledge of microbial environments associated with human skin, gastrointestinal tract and blood. The collective set of microorganisms influences metabolic processes, affects immune responses, and so directly or indirectly modulates disease. Rosacea is a skin condition of abnormal inflammation and vascular dysfunction, and its progression is affected by Demodex mites on the skin surface. When looking into the effects influencing development of rosacea, it is not only the skin microbiome change that needs to be considered. Changes in the intestinal microbiome and their circulating metabolites, as well as changes in the blood microbiome also affect the progression of rosacea. Recent research has confirmed the increased presence of bacterial genera like Acidaminococcus and Megasphera in the intestinal microbiome and Rheinheimera and Sphingobium in the blood microbiome of rosacea patients. In this review we discuss our current knowledge of the interactions between the immune system and the skin, gut and blood microbiome, with particular attention to rosacea diagnostic opportunities.

Demodex and eye disease: a review

Demodex is the most common parasite living on humans and yet little is understood about its pathogenicity with respect to the ocular surface. An increasing interest in Demodex over the past 20-years has increased our understanding of this mite and its pathogenetic role. This article begins with a review of the anatomy, life cycle, mode of transmission and advances in genetics that can distinguish between Demodex folliculorum and Demodex brevis, the only two Demodex species in humans. Additionally, a review of diagnostic procedures and existing and emerging ocular and systemic management options are presented. Despite the increasing interest in Demodex in the literature, there remains numerous obstacles for future studies, hence a section of this review is dedicated to the identification and proposal for future considerations. The lack of uniformity with respect to terminology, diagnostic technique and management approach for Demodex remain as obstacles for future study comparisons. This review summarised the current knowledge on Demodex and hopes to offer some recommendations for future directions in the study of Demodex in humans.

Rosacea is associated with conjoined interactions between physical barrier of the skin and microorganisms: A pilot study

Background

Rosacea is a common condition characterized by transient or persistent central facial erythema, and often papules and pustules. Currently, the role of bacterium in the development and progression of rosacea remains controversial. This study aimed to investigate the difference in the physiological conditions and microorganisms between the lesional and non‐lesional areas of papulopustular rosacea.

Methods

Twenty‐five French patients with papulopustular rosacea were enrolled in this pilot study. Each patient was subjected to clinical assessment, and the skin barrier function was tested in lesional and non‐lesional areas. In addition, samples from the lesional and non‐lesional areas were collected for bacterial culturing.

Results

Of all subjects included in the study, a lower skin conductivity was measured in lesional areas than in non‐lesional areas (43.5 ± 12.4 vs. 57.2 ± 11.6 U, P < .05), and a higher transepidermal water loss (TEWL) value was found in lesional areas than in non‐lesional areas (17.2 ± 5.9 vs. 14.2 ± 4.1 g/(m² h), P < .05). We found a lower TEWL in lesions in rosacea patients with bacterial dysbiosis than in those with bacterial balance (P < .05). In addition, there were significant differences in the skin conductivity and TEWL between lesional and non‐lesional areas in patients with bacterial dysbiosis (P < .001), and no significant differences were seen in patients with bacterial balance (P < .05).

Conclusion

The results of the present study demonstrate that the physiological features of rosacea are closely associated with the interactions between the host and the microorganisms.

Intense pulsed light (IPL) therapy for the treatment of meibomian gland dysfunction

BACKGROUND

Meibomian gland dysfunction (MGD) is the major cause of evaporative dry eye disease, which is the more prevalent form of dry eye disease. Intense pulsed light (IPL) therapy, involving treatment of the skin near the eyelids, has emerged as a potential treatment for MGD.

OBJECTIVES

To evaluate the effectiveness and safety of intense pulsed light (IPL) for the management dry eye disease resulting from meibomian gland dysfunction (MGD).

SEARCH METHODS

We searched CENTRAL, MEDLINE (Ovid), Embase Ovid and three trial registers for eligible clinical trials on 1 August 2019. There were no restrictions on publication status, date or language.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) studying the effectiveness or safety of IPL for treating MGD.

DATA COLLECTION AND ANALYSIS

Our outcomes of interest were the change from baseline in subjective dry eye symptoms, adverse events, changes to lipid layer thickness, tear break-up time (TBUT), tear osmolarity, eyelid irregularity, eyelid telangiectasia, meibomian gland orifice plugging, meibomian gland dropout, corneal sodium fluorescein staining and conjunctival lissamine green staining. Two review authors independently screened abstracts and full-text articles, extracted data from eligible RCTs and judged the risk of bias using the Cochrane tool. We reached consensus on any disagreements by discussion. We summarised the overall certainty of the evidence using the GRADE Working Group approach.

MAIN RESULTS

We included three RCTs, one from New Zealand, one from Japan and one from China, published between 2015 and 2019. Together, these trials enrolled 114 adults (228 eyes). Two studies used a paired-eye (inter-eye comparison) design to evaluate the effects of a sham (control) IPL treatment relative to an actual IPL treatment. One study randomised individuals to either an IPL intervention combined with meibomian gland expression (MGX), or MGX alone (standard therapy). The study follow-up periods ranged from 45 days to nine months. None of the trials were at low risk of bias in all seven domains. The first authors of two included studies were in receipt of funding from patents or the manufacturers of IPL devices. The funding sources and declaration of interests were not given in the report of the third included trial. All three trials evaluated the effect of IPL on dry eye symptoms, quantified using the Standard Patient Evaluation of Eye Dryness (SPEED) questionnaire. Pooling data from two trials that used a paired-eye design, the summary estimate for these studies indicated little to no reduction in dry eye symptoms with IPL relative to a sham intervention (mean difference (MD) -0.33 units, 95% confidence interval (CI) -2.56 to 1.89; I² = 0%; 2 studies, 144 eyes). The other study was not pooled as it had a unit-of-analysis error, but reported a reduction in symptoms in favour of IPL (MD -4.60, 95% CI -6.72 to -2.48; 84 eyes). The body of evidence for this outcome was of very low certainty, so we are uncertain about the effect of IPL on dry eye symptoms. There were no relevant combinable data for any of the other secondary outcomes, thus the effect of IPL on clinical parameters relevant to dry eye disease are currently unclear. For sodium fluorescein TBUT, two studies indicated that there may be an improvement in favour of IPL (MD 2.02 seconds, 95% CI 0.87 to 3.17; MD 2.40 seconds, 95% CI 2.27 to 2.53; 172 eyes total; low-certainty evidence). We are uncertain of the effect of IPL on non-invasive tear break-up time (MD 5.51 seconds, 95% CI 0.79 to 10.23; MD 3.20, 95% CI 3.09 to 3.31 seconds; two studies; 140 eyes total; very low-certainty evidence). For tear osmolarity, one study indicated that there may be an improvement in favour of IPL (MD -7.00 mOsmol/L, 95% -12.97 to -1.03; 56 eyes; low-certainty evidence). We are uncertain of the effect of IPL on meibomian gland orifice plugging (MD -1.20 clinical units, 95% CI -1.24 to -1.16; 84 eyes; very low-certainty evidence). We are uncertain of the effect of IPL on corneal sodium fluorescein staining. One study reported no evidence of a difference between the IPL and sham intervention arms at three months of follow-up (P = 0.409), and a second study reported data favouring IPL (MD -1.00 units, 95% CI -1.07 to -0.93 units; 172 eyes in total; very low-certainty evidence). We considered the incidence of adverse events at the study endpoint, as a measure of safety. As most trials did not specifically report adverse events, the safety of IPL as a treatment for MGD could also not be determined with any certainty. Very low-certainty results from individual studies suggest some adverse effects that may be experienced by participants, include mild pain and burning, and the potential for partially losing eyelashes (due to clinician error).

AUTHORS' CONCLUSIONS

This systematic review finds a scarcity of RCT evidence relating to the effectiveness and safety of IPL as a treatment for MGD. Whether IPL is of value for modifying the symptoms or signs of evaporative dry eye disease is currently uncertain. Due to a lack of comprehensive reporting of adverse events, the safety profile of IPL in this patient population is also unclear. The current limitations in the evidence base should be considered by clinicians using this intervention to treat MGD, and outlined to individuals potentially undergoing this procedure with the intent of treating dry eye disease. The results of the 14 RCTs currently in progress will be of major importance for establishing a more definitive answer regarding the effectiveness and safety of IPL for treating MGD. We intend to update this review when results from these trials become available.

Demodex folliculorum infestations in common facial dermatoses: acne vulgaris, rosacea, seborrheic dermatitis

Background

Demodex mites are found on the skin of many healthy individuals. Demodex mites in high densities are considered to play a pathogenic role.

Objective

To investigate the association between Demodex infestation and the three most common facial dermatoses: acne vulgaris, rosacea and seborrheic dermatitis.

Methods

This prospective, observational case-control study included 127 patients (43 with acne vulgaris, 43 with rosacea and 41 with seborrheic dermatitis) and 77 healthy controls. The presence of demodicosis was evaluated by standardized skin surface biopsy in both the patient and control groups.

Results

In terms of gender and age, no significant difference was found between the patients and controls (p > 0.05). Demodex infestation rates were significantly higher in patients than in controls (p = 0.001). Demodex infestation rates were significantly higher in the rosacea group than acne vulgaris and seborrheic dermatitis groups and controls (p = 0.001; p = 0.024; p = 0.001, respectively). Demodex infestation was found to be significantly higher in the acne vulgaris and seborrheic dermatitis groups than in controls (p = 0.001 and p = 0.001, respectively). No difference was observed between the acne vulgaris and seborrheic dermatitis groups in terms of demodicosis (p = 0.294).

Study limitations

Small sample size is a limitation of the study. The lack of an objective scoring system in the diagnosis of Demodex infestation is another limitation.

Conclusion

The findings of the present study emphasize that acne vulgaris, rosacea and seborrheic dermatitis are significantly associated with Demodex infestation. Standardized skin surface biopsy is a practical tool in the determination of Demodex infestation.

Use of Intense Pulsed Light to Mitigate Meibomian Gland Dysfunction for Dry Eye Disease

Dry Eye Disease (DED) is a common ocular condition that needs prompt diagnosis and careful treatment interventions. If left untreated, it can lead to numerous sight-threatening complications, including ulceration of the cornea, blepharitis, alterations of the tear film, conjunctivitis, and in severe cases, may lead to scarring, thinning, and even perforation of the cornea. Intense pulsed light (IPL) is a non-laser high-intensity light source that has shown to play a valuable role in dry eye disease. Recent evidence from various research works has shown that IPL modifies the mechanism of meibomian gland dysfunction (MGD), which helps to relieve the symptoms of DED. In this review, we demonstrated the mechanism of action of IPL, including its benefits on DED. The emerging evidence shows that the role of IPL in DED is novel and therapeutic. These results direct us to conclude that IPL is a potentially beneficial tool and essential future therapy for dry eye disease. Advances in the treatment of DED will lead to a better quality of life. However, tools to recognize potentially severe side effects of DED earlier in order to treat or prevent them must be developed.

The Skin and Gut Microbiome and Its Role in Common Dermatologic Conditions

Microorganisms inhabit various areas of the body, including the gut and skin, and are important in maintaining homeostasis. Changes to the normal microflora due to genetic or environmental factors can contribute to the development of various disease states. In this review, we will discuss the relationship between the gut and skin microbiome and various dermatological diseases including acne, psoriasis, rosacea, and atopic dermatitis. In addition, we will discuss the impact of treatment on the microbiome and the role of probiotics.

Nuclear Factor Kappa-B Is Enriched in Eyelid Specimens of Rosacea: Implications for Pathogenesis and Therapy

PURPOSE

To assess the role of nuclear factor kappa-B (NFKB) in cutaneous specimens of rosacea and unaffected tissue.

METHODS

Immunohistochemical staining was performed for the activated, phosphorylated variant of NFKB (pNFKB) in eyelid specimens of rosacea (n = 12) and normal, healthy tissue (n = 12). The numbers of positively staining cells/40× microscopic field were counted across 5 consecutive fields. Additionally, quantitative Western blotting was carried out for pNFKB and NFKB in specimens of rosacea (n = 15) and normal controls (n = 14). Statistical comparisons were performed via a dedicated software package.

RESULTS

The mean number of cells/40× microscopic field that stained positively for pNFKB was 18.4 (standard deviation = 15.3) for control patients and 39.3 (standard deviation = 16.9) for rosacea patients, and the difference between the 2 groups was statistically significant (P = .0024). On Western blotting, the mean ratios of pNFKB:NFKB for control and rosacea patients measured 0.58 (standard deviation = 0.81) and 3.11 (standard deviation = 3.53), respectively. The 2 groups were statistically significantly different (P = .0002).

CONCLUSIONS

The activated form of NFKB is enriched in rosacea, indicating a role for this pathway in the pathogenesis of this disease. Interference with NFKB signaling may represent a novel therapy for rosacea as clinical agents become available. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.

Safety and efficacy of 4-terpineol against microorganisms associated with blepharitis and common ocular diseases

OBJECTIVE

Microbial infection has been reported to cause blepharitis, conjunctivitis and keratitis. We evaluated the safety and efficacy of a foam formulation of 2% 4-terpineol (T4O) against common ocular microorganisms.

MATERIAL AND METHODS

The antimicrobial effect of a 2% T4O formulation was evaluated by the United States Pharmacopeia 51 (USP <51>) antimicrobial effectiveness test for 14 and 28 days, as well as by a Time Kill Study (ASTM E2315) with a 60 s exposure time. Its potential of causing skin and ocular irritation was evaluated by the Repeated Insult Patch Test and the Hen's Egg Chorioallantoic Membrane Test, respectively.

RESULTS AND DISCUSSION

It was seen that 2% T4O formulation did not cause ocular irritation, skin irritation, sensitisation or allergic contact dermatitis in human subjects. Most importantly, it killed microorganisms listed in USP <51> at both 14 and 28 days and exerted a rapid killing effect within 60 s against 13 bacteria, 1 fungus and Acanthamoeba castellanii.

CONCLUSION

The above finding suggests that 2% T4O formulation is safe and effective in killing microorganisms related to common ocular and skin infective diseases.

TRANSLATIONAL RELEVANCE

Although the clinical efficacy in treating ocular disease was not directly studied; this foam formulation containing 2% T4O, based on the in vitro results of this work, demonstrated that it can potentially be used as a preservative-free cleansing agent for ocular hygiene maintenance due to its ability to exert a broad-spectrum antimicrobial effect without causing ocular or skin irritation.

Analysis of the effect of temperature on protein abundance in Demodex-associated Bacillus oleronius

A potential role for bacteria in the induction of rosacea has been suggested. The aim of this work was to characterise the effect of temperature on the production of immunostimulatory proteins by Bacillus oleronius-a bacterium to which rosacea patients show sera reactivity and which was originally isolated from a Demodex mite from a rosacea patient. The affected skin of rosacea patients is at a higher temperature than unaffected skin, and it was postulated that this might alter the protein expression pattern of B. oleronius. B. oleronius growth was reduced at 37°C compared to 30°C but resulted in increased expression of the immune-reactive 62kDa protein (1.65 fold [P < 0.05]). Proteomic analysis revealed increased abundance of a wide range of proteins involved in the stress response (e.g. stress proteins [21.7-fold increase], phosphocarrier protein HPr [438.5-fold increase], 60 kDa chaperonin [12.6-fold increase]). Proteins decreased in abundance after growth at 37°C included ferredoxin (325-fold decrease) and peptidase (244-fold decrease). This work indicates that the increased skin temperature of rosacea patients may alter the growth and protein production pattern of B. oleronius and lead to the greater production of immuo-stimulatory proteins.

Endosymbiosis and its significance in dermatology

Proposed at the beginning of the twentieth century to explain the origin of eukaryotic organelles from prokaryotes, endosymbiosis is now medically defined by various interaction patterns between microorganisms and their residing hosts, best exemplified by the bacterial endosymbiont Wolbachia identified in arthropods and filarial nematodes, which can influence normal development, reproduction, survival and transmission of the hosts. Based on the transmission modes, vertical or horizontal, and the function of the endosymbionts, the host-symbiont dependence can be divided into primary or secondary. In dermatology, the role of endosymbionts in skin ectoparasitosis has aroused great interests in the past years. Riesia pediculicola is a primary bacterial endosymbiont in body lice Pediculus humanus, and supplement their hosts with vitamin B, especially pantothenic acid. In cimicosis, the Gram-negative Wolbachia can synthesize biotin and riboflavin, which are crucial for the growth and reproduction of the bedbug Cimex lectularius. In human demodicosis and rosacea, further study is required to prove the pathogenic role of the Gram-negative bacteria Bacillus oleronius or the Gram-positive bacteria Bacillus cereus demonstrated in the Demodex mites. The high infection rate of adult female ticks Ixodes ricinus with the Gram-negative bacteria Midichloria mitochondrii present in the mitochondria in diverse ovarian cells, with the high seroprevalence rate in tick-exposed subjects, raises the possibility that this non-pathogenic endosymbiont may play a role in immune response and successful transmission of the tick-borne pathogen. The anaerobic protozoan Trichomonas vaginalis and bacteria Mycoplasma hominis are two obligate parasites in the urogenital epithelium, with partially overlapping symptoms. Intracellular localization of Mycoplasma hominis can avoid host immune response and penetration of antibiotics, while Trichomonas vaginalis infected with Mycoplasma hominis seems to have a higher cytopathic activity and amoeboid transformation rate. Further study on the biology and pathogenesis of different endosymbionts in dermatological parasitosis will help for the development of new treatment modalities.

A Review of the Current Modalities for the Treatment of Papulopustular Rosacea

Papulopustular rosacea is characterized by papules and pustules in the central facial region. We review the literature surrounding the treatment of papulopustular rosacea. PubMed, EMBASE, and Cochrane (Central) databases searches of articles published from 1980 to 2015 were performed using the MeSH terms or keywords "rosacea" and "clinical trial." Additional searches were performed to include rosacea and each treatment modality used. Topical metronidazole, azelaic acid, ivermectin, and oral doxycycline have the most robust data to support their use. Variation in assessment tools and a lack of clinical trial standardization makes comparison of therapeutic options difficult.

Significant correlation between meibomian gland dysfunction and keratitis in young patients with Demodex brevis infestation

Aims

To report the clinical characteristics and correlation between meibomian gland dysfunction (MGD) and keratitis in young patients with ocular demodicosis.

Methods

Observational case series of 60 patients younger than 35 years with ocular demodicosis, of which the diagnosis was based on microscopic counting of Demodex folliculorum and D. brevis of epilated lashes. Severity of keratitis and MGD was graded by photography and meibography, respectively, in a masked fashion.

Results

MGD was detected in 54/60 (90%) patients with the loss of meibomian gland in the upper lid more than the lower lid (p<0.001). Blepharoconjunctivitis and a variety of corneal pathologies were noted in 47/60 (78.3%) and 39/60 (65%) patients, respectively. For a total of 120 eyes, normal cornea was noted in 53 (44.2%) eyes, superficial punctate keratitis or limbitis was noted in 17 (14.2%), while corneal stromal infiltration was found in 50 (41.7%) eyes. Both univariate and multivariate analyses showed that the severity of meibomian gland loss was significantly correlated with higher D. brevis count and more severe keratitis (all p<0.05). Rapid resolution of keratitis and blepharoconjunctivitis was accompanied by significant reduction of the Demodex count in 48 patients receiving lid scrub directed to kill mites.

Conclusions

There is a significant correlation between MGD and keratitis in young patients with ocular demodicosis especially inflicted by D. brevis.

Diet and rosacea: the role of dietary change in the management of rosacea

Dietary change may play a role in the therapy of rosacea. Certain foods and beverages may act as "triggers" for rosacea exacerbations. These may be divided into heat-related, alcohol-related, capsaicin-related, and cinnamaldehyde-related. One potential pathogenic mechanism may be via the activation of transient receptor potential cation channels, which result in neurogenic vasodilatation. Further research is needed on the role of the gut skin connection in rosacea. Epidemiologic studies suggest that patients with rosacea have a higher prevalence of gastrointestinal disease, and one study reported improvement in rosacea following successful treatment of small intestinal bacterial overgrowth. While further research is required in this area, patients may be advised on measures to support a healthy gut microbiome, including the consumption of a fiber-rich (prebiotic) diet.

[Rosacea: New data for better care]

In the last 10 years, numerous studies have been published that throw new light on rosacea, in all areas of the disease. This overview summarises all the key developments, based on the indexed bibliography appearing in Medline between 2007 and 2017. Recent epidemiological data show that the prevalence of the disease is doubtless greater than estimated hitherto (more than 10% of adults in some countries) and that we should not overlook rosacea in subjects with skin phototypes V or VI, a condition that exists on all continents. A new classification of rosacea by phenotype comprising major and minor signs has been put forward; it provides a more rational approach to suitable management based upon symptoms, the severity of which may be graded into 5 classes. The treatments with the best-demonstrated efficacy (updated Cochrane study) are topical metronidazole, azelaic acid and ivermectin, and oral doxycycline; isotretinoin is effective against resistant forms but is off-label. In ocular rosacea, the reference treatment is doxycycline in combination with topical therapy of the eyelids. The physiopathology is complex and involves several factors: vascular (vasodilatation, vascular growth factors), neurovascular (hypersensitivity, neuropathic pain, neuropeptides), infectious (Demodex folliculorum and its microbiota) and inflammatory (abnormal production of pro-inflammatory peptides of the innate immune system). In addition, there is a genetic predisposition as demonstrated by the weight of familial history and comparison of homozygous and heterozygous twins. There is also activation of several genes involved in immunity, inflammation and lipid metabolism; the theory of hydrolipid film anomalies has been posited once more. There has thus been a tremendous leap forward in the field of rosacea research, with therapeutic progress and improved understanding of the underlying mechanisms, which should enable the future development of more targeted treatments as well as global management of this disease, which has major social and emotional consequences on the life of patients.

Role of Demodex mite infestation in rosacea: A systematic review and meta-analysis

BACKGROUND

The reported prevalence and degrees of Demodex mite infestation in rosacea vary widely.

OBJECTIVE

We sought to conduct an evidence-based meta-analysis of the prevalence and degrees of Demodex mite infestation in patients with rosacea.

METHODS

Systematic literature review and meta-analysis were conducted. Odds ratios for prevalence of infestation and standardized mean difference (SMD) for Demodex density in patients with rosacea were pooled. Subgroup analysis for type of rosacea, control group, and sampling and examination methods were also performed.

RESULTS

Twenty-three case-control studies included 1513 patients with rosacea. Compared with the control patients, patients with rosacea were more likely to be infested by Demodex mites [odds ratio, 9.039; 95% confidence interval (CI), 4.827-16.925] and had significantly higher Demodex density (SMD, 1.617; 95% CI, 1.090-2.145). Both erythematotelangiectatic rosacea (SMD, 2.686; 95% CI, 1.256-4.116) and papulopustular rosacea (SMD, 2.804; 95% CI, 1.464-4.145) had significantly higher Demodex density than did healthy control patients.

LIMITATIONS

Interstudy variability was high, and a causal relationship could not be established by case-control studies.

CONCLUSIONS

Patients with rosacea had significantly higher prevalence and degrees of Demodex mite infestation than did control patients. Demodex mites may play a role in both erythematotelangiectatic rosacea and papulopustular rosacea.

Intense pulsed light for evaporative dry eye disease

There is a clear association between dry eye disease (DED) and skin inflammatory diseases occurring in close proximity to the eyelids, such as facial skin rosacea. Intense pulsed light (IPL) is widely accepted as a treatment for skin rosacea. A number of recent studies demonstrated that, in patients suffering from meibomian gland dysfunction (MGD), IPL therapy also reduces signs and symptoms of DED. Despite these encouraging results, in the context of DED and MGD, the mechanisms of action of IPL are not well understood. The purpose of this review was to raise the potential mechanisms of action and to discuss their plausibility.

Bacillus cereus strain isolated from Demodex folliculorum in patients with topical steroid-induced rosaceiform facial dermatitis

The aim of the study was to identify Bacillus species from the Demodex folliculorum of patients with topical steroidinduced facial rosaceiform dermatitis. Of the 75 patients examined, 20% had clinical spinulosis, while 18.66% had dermoscopic features of Demodex: follicular plugs and tails. Of the 17.33% positive patients identified upon microscopy for Demodex, samples for bacterial culture were plated on trypticase soy Colombia agar. Identification was performed by microorganisms grown method mass spectrometry. We identified a strain of Bacillus cereus.

Association study of Demodex bacteria and facial dermatoses based on DGGE technique

The role of bacteria is unclear in the facial skin lesions caused by Demodex. To shed some light on this issue, we conducted a case-control study comparing cases with facial dermatoses with controls with healthy skin using denaturing gradient gel electrophoresis (DGGE) technique. The bacterial diversity, composition, and principal component were analyzed for Demodex bacteria and the matched facial skin bacteria. The result of mite examination showed that all 33 cases were infected with Demodex folliculorum (D. f), whereas 16 out of the 30 controls were infected with D. f, and the remaining 14 controls were infected with Demodex brevis (D. b). The diversity analysis showed that only evenness index presented statistical difference between mite bacteria and matched skin bacteria in the cases. The composition analysis showed that the DGGE bands of cases and controls were assigned to 12 taxa of 4 phyla, including Proteobacteria (39.37-52.78%), Firmicutes (2.7-26.77%), Actinobacteria (0-5.71%), and Bacteroidetes (0-2.08%). In cases, the proportion of Staphylococcus in Firmicutes was significantly higher than that in D. f controls and D. b controls, while the proportion of Sphingomonas in Proteobacteria was significantly lower than that in D. f controls. The between-group analysis (BGA) showed that all the banding patterns clustered into three groups, namely, D. f cases, D. f controls, and D. b controls. Our study suggests that the bacteria in Demodex should come from the matched facial skin bacteria. Proteobacteria and Firmicutes are the two main taxa. The increase of Staphylococcus and decrease of Sphingomonas might be associated with the development of facial dermatoses.

Activation of Neutrophils via IP3 Pathway Following Exposure to Demodex-Associated Bacterial Proteins

Rosacea is a chronic inflammatory condition that predominantly affects the skin of the face. Sera from rosacea patients display elevated reactivity to proteins from a bacterium (Bacillus oleronius) originally isolated from a Demodex mite from a rosacea patient suggesting a possible role for bacteria in the induction and persistence of this condition. This work investigated the ability of B. oleronius proteins to activate neutrophils and demonstrated activation via the IP3 pathway. Activated neutrophils displayed increased levels of IP1 production, F-actin formation, chemotaxis, and production of the pro-inflammatory cytokines IL-1β and IL-6 following stimulation by pure and crude B. oleronius protein preparations (2 μg/ml), respectively. In addition, neutrophils exposed to pure and crude B. oleronius proteins (2 μg/ml) demonstrated increased release of internally stored calcium (Ca(2+)), a hallmark of the IP3 pathway of neutrophil activation. Neutrophils play a significant role in the inflammation associated with rosacea, and this work demonstrates how B. oleronius proteins can induce neutrophil recruitment and activation.

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

Rosacea is a chronic cutaneous inflammatory disease that affects the facial skin. Clinically, rosacea can be categorized into papulopustular, erythematotelangiectatic, ocular, and phymatous rosacea. However, the phenotypic presentations of rosacea are more heterogeneous. Although the pathophysiology of rosacea remains to be elucidated, immunologic alterations and neurovascular dysregulation are thought to have important roles in initiating and strengthening the clinical manifestations of rosacea. In this article, we present the possible molecular mechanisms of rosacea based on recent laboratory and clinical studies. We describe the genetic predisposition for rosacea along with its associated diseases, triggering factors, and suggested management options in detail based on the underlying molecular biology. Understanding the molecular pathomechanisms of rosacea will likely aid toward better comprehending its complex pathogenesis.

Trends in the frequency of original research in acne vulgaris, rosacea, dermatitis, psoriasis, skin cancer, and skin infections, 1970-2010

CONTEXT

Medical journals have allowed researchers to share their latest discoveries, especially in the most common diseases affecting patients worldwide.

OBJECTIVE

To analyze trends in the frequency of original research into common dermatologic diseases from 1970 to 2010.

DESIGN

A retrospective review of the Journal of the American Academy of Dermatology and the Archives of Dermatology was performed using the MEDLINE database. All original research articles published between 1970 and 2010, by quinquennium, dealing with acne vulgaris, rosacea, skin cancer, dermatitis, psoriasis, or skin infections were included.

MAIN OUTCOME MEASURE

Total number of publications dealing with each dermatologic topic considered.

RESULTS

The frequency of research into acne vulgaris and rosacea decreased from 24% in 1970 to 5.1% in 2010. Psoriasis research increased in frequency from 17.6% to 26.5% from 2000 to 2010, and skin cancer research increased from 4% in 1970 to 48% in 2010.

CONCLUSIONS

Topics that experienced early advancements in research, such as acne vulgaris and rosacea, demonstrated a decreasing trend in the frequency of publication. Published psoriasis research has increased in frequency since 2000, most likely because of the discovery of biologics. Finally, skin cancer research has continued to increase in frequency of publication, paralleling the increasing incidence of skin cancer.

Recent advances on ocular Demodex infestation

PURPOSE OF REVIEW

To summarize recent advances on ocular Demodex infestation.

RECENT FINDINGS

Demodex infestation is a potential cause of ocular surface inflammation. The pathogenesis of Demodex in eliciting ocular surface inflammation has been further clarified. Cliradex is currently the treatment of choice, it comprises the most active ingredient of tea tree oil, that is terpinen-4-ol, which helps eradicate Demodex mites and reduce ocular surface inflammation.

SUMMARY

Ocular demodicosis is a common but overlooked eye disease that manifests a number of morbidities. Demodex folliculorum causes chronic anterior blepharitis whereas Demodex brevis causes posterior blepharitis, meibomian gland dysfunction, recurrent chalazia, and refractory keratoconjunctivitis. The lash sampling and microscopic counting method and in-vivo confocal microscopy are key diagnostic methods. Cliradex shows promising potential to reduce Demodex counts with additional antibacterial, antifungal, and anti-inflammatory actions.

Rosacea: part I. Introduction, categorization, histology, pathogenesis, and risk factors

Rosacea is a chronic inflammatory skin condition that affects approximately 16 million Americans. Four distinct subtypes of rosacea have been recognized, with transient and nontransient facial flushing, telangiectasia, and inflammatory papules and pustules being among the more commonly recognized features. Although the exact pathogenesis of rosacea is unknown, dysregulation of the innate immune system, overgrowth of commensal skin organisms, and aberrant neurovascular signaling may all have a role in promoting the clinical features of rosacea.