A comparative study of childhood psoriasis and atopic dermatitis and greater understanding of the overlapping condition, psoriasis-dermatitis

Atopic Dermatitis and Psoriasis: Similarities and Differences in Metabolism and Microbiome

Atopic dermatitis and psoriasis are common chronic inflammatory diseases of high incidence that share some clinical features, including symptoms of pruritus and pain, scaly lesions, and histologically, acanthosis and hyperkeratosis. Meanwhile, they are both commonly comorbid with metabolic disorders such as obesity and diabetes, indicating that both diseases may exist with significant metabolic disturbances. Metabolomics reveals that both atopic dermatitis and psoriasis have abnormalities in a variety of metabolites, including lipids, amino acids, and glucose. Meanwhile, recent studies have highlighted the importance of the microbiome and its metabolites in the pathogenesis of atopic dermatitis and psoriasis. Metabolic alterations and microbiome dysbiosis can also affect the immune, inflammatory, and epidermal barrier, thereby influencing the development of atopic dermatitis and psoriasis. Focusing on the metabolic and microbiome levels, this review is devoted to elaborating the similarities and differences between atopic dermatitis and psoriasis, thus providing insights into the intricate relationship between both conditions.

[Inflammatory dermatoses in children and adolescents : Diagnosis and treatment of atopic dermatitis and psoriasis]

Atopic dermatitis (AD) and psoriasis belong to the most common inflammatory dermatoses that we treat in everyday clinical practice. AD manifests in more than 70% of cases before the age of 5 years. Approximately one-third of psoriasis patients report on onset of disease in the first two decades of life. Here, we are going to review both disorders in the light of pediatric dermatology. We are going to discuss selected subtypes and present clues for further examination with respect to the differential diagnoses and comorbidities. The article provides insight into current therapeutic developments that are relevant for the treatment of children and adolescents.

Psoriasis dermatitis: a new entity or a different phenotypic expression of psoriasis and atopic dermatitis?

BACKGROUND

Psoriasis (P) and atopic dermatitis (AD) share some common characteristics. The resulting clinical picture with shared manifestations is a new entity called psoriasis dermatitis (PD), atopic psoriasis or psorema. The purpose of this study was to identify the clinical manifestations of this new dermatological condition, focusing on the adult population.

METHODS

We recruited adult patients from two outpatient clinics, the "severe psoriasis" and the "adult atopic dermatitis," between January 1st, 2021, and December 31st, 2021. The 26 patients meeting the inclusion criteria were followed for 12 months, and two control groups of patients were enrolled in the same period.

RESULTS

The frequencies of the variables examined within the patients affected by PD were compared with those of P or AD group. The age at disease onset was significantly higher in PD patients and the duration of symptoms was also significantly lower in PD patients, compared to both P and AD groups. Affected areas were similar between PD and P, instead the scalp, feet and genitals were more frequently involved in the PD group than in the AD group.

CONCLUSIONS

P and AD seem part of a spectrum rather than a dichotomy, where PD is an entity in the middle of this spectrum.

Skin barrier-inflammatory pathway is a driver of the psoriasis-atopic dermatitis transition

As chronic inflammatory conditions driven by immune dysregulation are influenced by genetics and environment factors, psoriasis and atopic dermatitis (AD) have traditionally been considered to be distinct diseases characterized by different T cell responses. Psoriasis, associated with type 17 helper T (Th17)-mediated inflammation, presents as well-defined scaly plaques with minimal pruritus. AD, primarily linked to Th2-mediated inflammation, presents with poorly defined erythema, dry skin, and intense itching. However, psoriasis and AD may overlap or transition into one another spontaneously, independent of biological agent usage. Emerging evidence suggests that defects in skin barrier-related molecules interact with the polarization of T cells, which forms a skin barrier-inflammatory loop with them. This loop contributes to the chronicity of the primary disease or the transition between psoriasis and AD. This review aimed to elucidate the mechanisms underlying skin barrier defects in driving the overlap between psoriasis and AD. In this review, the importance of repairing the skin barrier was underscored, and the significance of tailoring biologic treatments based on individual immune status instead of solely adhering to the treatment guidelines for AD or psoriasis was emphasized.

Psoriasis dermatitis, a common phenotype of early forms of both psoriasis and atopic dermatitis in children: A prospective multicenter study

BACKGROUND

Psoriasis (Ps) and atopic dermatitis (AD) are chronic systemic immune-mediated diseases that can coexist in an overlapping condition called psoriasis dermatitis (PD). PD patients have intermediate lesions with characteristics of both Ps and AD. PD is very rare in adults but much more frequent in children. Little is known, however, about the course of PD in the pediatric population. The aim of this study was to evaluate the percentage of PD cases in children that evolved to a definite form of Ps or AD and to identify any clinical or epidemiological variables that could predict the course of the disease.

METHODS

We performed a prospective multicenter cohort study of children diagnosed with PD between January 2018 and December 2020. We collected participants' clinical and epidemiological characteristics, and pediatric dermatologists determined the percentage of participants who developed Ps or AD.

RESULTS

The study included 24 children with PD, with a median age of 7.0 years. After a median follow-up period of 31 months, 83.3% of cases had evolved to a definite form of Ps or AD (44.4% to Ps and 38.9% to AD). Younger age and family history of Ps were associated with progression to AD. Participants who progressed to AD or Ps had a longer follow-up than those with an unchanged PD diagnosis.

CONCLUSIONS

Given sufficient time, a large percentage of PD cases in children will evolve into Ps or AD. Long-term clinical follow-up is necessary for a correct diagnosis.

IL-17A inhibitors alleviate Psoriasis with concomitant restoration of intestinal/skin microbiota homeostasis and altered microbiota function

Background

Disturbed gut microbiota and associated metabolic dysfunction exist in Psoriasis. Despite the growing use of interleukin-17 inhibitor (anti-IL17) therapy, the effect of anti-IL17 on gut/skin microbiota function is not fully understood in patients with Psoriasis.

Objective

Therefore, we explored whether Psoriasis is associated with alterations in selected gut/skin microbiota in a study cohort, and a longitudinal cohort study to reveal the effects of IL-17A inhibitor treatment on gut microbiota in Psoriasis.

Methods

In a case-control study, 14 patients with Psoriasis and 10 age, sex and body mass index-matched Healthy Controls were recruited. Longitudinal mapping of the gut microbiome was performed using 16S rRNA gene sequencing. Mouse models were used to further study and validate the interrelationship between the skin microbiome and the gut microbiome in Psoriasis. PICRUST2 was applied to predict the function of the bacterial community.

Results

In Psoriasis patients, gut microbiota dysbiosis was present with increased heterogeneity: decreased Bacteroidota and increased Firmicutes as well as Actinobacteriota predominating in Psoriasis. Escherichia-Shigella enrichment was associated with reduction in serum levels of total bile acid and markers in Apoptotic pathways. After IL-17A inhibitor treatment in Psoriasis patients, longitudinal studies observed a trend toward a normal distribution of the gut microbiome and modulation of apoptosis-related metabolic pathways. Results from a mouse model showed dysregulation of the skin microbiota in Psoriasis characterized by Staphylococcus colonization.

Conclusion

The psoriatic gut/skin microbiota exhibits loss of community stability and pathogen enrichment. IL-17A inhibitors restore microbiota homeostasis and metabolic pathways, reduce pro-inflammatory cytokine expression, and alleviate symptoms in patients with Psoriasis.

Genomic Profiling of the Overlap Phenotype between Psoriasis and Atopic Dermatitis

Clinical overlaps between psoriasis and atopic dermatitis (AD) are sometimes undiscernible, and there is no consensus on whether to treat the overlap phenotype as psoriasis or AD. We enrolled 41 patients diagnosed with either psoriasis or AD and clinically re-stratified them into classic psoriasis (n = 11), classic AD (n = 13), and the overlap phenotype between psoriasis and AD (n = 17). We compared the gene expression profiles of lesional and nonlesional skin biopsy tissues and the proteomic profiles of blood samples among the three comparison groups. Global mRNA expression and T-cell subset cytokine expression in the skin and protein biomarker elevation in the blood of the overlap phenotype were consistent with the profiles of psoriasis and different from the profiles of AD. Unsupervised k-means clustering indicated that the best number of distinct clusters for the total population of the three comparison groups was two, and the two clusters of psoriasis and AD were differentiated by gene expression. Our study suggests that the clinical overlap phenotype between psoriasis and AD has dominant molecular features of psoriasis, and genomic biomarkers can differentiate psoriasis and AD at molecular levels in patients with a spectrum of psoriasis and AD.

Knowledge Mapping and Research Hotspots of Comorbidities in Psoriasis: A Bibliometric Analysis from 2004 to 2022

Background and Objectives: Psoriasis is a chronic inflammatory disease whose impact on health is not only limited to the skin, but is also associated with multiple comorbidities. Early screening for comorbidities along with appropriate treatment plans can provide a positive prognosis for patients. This study aimed to summarize the knowledge structure in the field of psoriasis comorbidities and further explore its research hotspots and trends through bibliometrics. Materials and Methods: A search was conducted in the core collection of the Web of Science for literature on comorbidities of psoriasis from 2004 to 2022. VOSviewer and CiteSpace software were used for collaborative network analysis, co-citation analysis of references, and keyword co-occurrence analysis on these publications. Results: A total of 1803 papers written by 6741 authors from 81 countries was included. The publications have shown a progressive increase since 2004. The United States and Europe were at the forefront of this field. The most prolific institution was the University of California, and the most productive author was A. Armstrong. Research has focused on "psoriatic arthritis", "metabolic syndrome", "cardiovascular disease", "psychosomatic disease", "inflammatory bowel disease", "prevalence", "quality of life", and "risk factor" in the past 18 years. Keywords such as "biologics" and "systemic inflammation", have been widely used recently, suggesting current research hotspots and trends. Conclusions: Over the past 18 years, tremendous progress has been made in research on psoriasis comorbidity. However, collaborations among countries, institutions, and investigators are inadequate, and the study of the mechanisms of interaction between psoriasis and comorbidities and management of comorbidities is insufficient. The treatment of comorbidities with biologic agents, screening of comorbidities, and multidisciplinary co-management are predicted to be the focus of future research.

Children atopic dermatitis: Diagnosis, mimics, overlaps, and therapeutic implication

Atopic dermatitis (AD) is a chronic inflammatory, itching skin with a significant psychosocial impact on patients and relatives. In adults and adolescents besides flexural eczema, head and neck eczema, and hand eczema, which are the most frequent clinical phenotypes (84.9% and 84.2%, respectively), there are also other possible presentation such as, portrait-like dermatitis (20.1%), diffuse eczema (6.5%), eczema nummulare-like (5.8%), prurigo nodularis-like (2.1%) and erythrodermia (0.7%). Diagnosis can be easy due to the typically distributed eczematous lesions, albeit with age-related differences, However, it is also extremely heterogeneous in severity, course, and sometimes particular clinical features. Currently, there are no better diagnostic criteria than an experienced dermatologist for the diagnosis of AD. Misdiagnosis and delayed treatment will have an impact not only on the child's physical health, but also and especially on the child's psychological health. The aim of our review was to group the main differential diagnoses in pediatric age where the diagnosis can often hide many pitfalls.

Overlapping Features of Psoriasis and Atopic dermatitis: From Genetics to Immunopathogenesis to Phenotypes

Psoriasis (PSO) and atopic dermatitis (AD) were once considered to be mutually exclusive diseases, but gradually regarded as a spectrum of disease. Shared genetic loci of both diseases were noted in some populations, including Chinese. Shared immunopathogenesis involving Th17, Th1, Th22 cells, or even IL-13 was found in certain stages or phenotypes. This review discusses the overlapping genetic susceptibility, shared cytokines, immune-mediated comorbidities, and clinical presentations. Overlapping conditions could be classified into mainly PSO lesions with AD features or vice versa, concomitant PSO and AD, or disease transformation as a result of biologics treatment.

Annoying Psoriasis and Atopic Dermatitis: A Narrative Review

Skin is an important organ that mainly functions as a barrier. Skin diseases can damage a person's self-confidence and reduce their willingness to socialize, as well as their social behavior and willingness. When the skin appearance is abnormal, in addition to affecting the quality of life, it often leads to personal, social, and psychological dysfunction and even induces depression. Psoriasis and atopic dermatitis are common chronic skin diseases. Their prevalence in the world is 3-10%, and there is an increasing trend year by year. These congenital or acquired factors cause the dysfunction of the immune system and then destroy the barrier function of the skin. Because these patients are flooded with a variety of inflammatory mediators, this causes skin cells to be in chronic inflammation. Therefore, psoriasis and atopic dermatitis are also considered systemic chronic inflammatory diseases. In the healthcare systems of developed countries, it is unavoidable to spend high costs to relieve symptoms of psoriasis and atopic dermatitis patients, because psoriasis and atopic dermatitis have a great influence on individuals and society. Giving a lot of attention and developing effective treatment methods are the topics that the medical community must work on together. Therefore, we used a narrative review manuscript to discuss pathogenesis, clinical classification, incidence, and treatment options, including topical medication, systemic therapeutics, immunosuppressive medication for psoriasis, and atopic dermatitis, as well as also comparing the differences between these two diseases. We look forward to providing readers with comprehensive information on psoriasis and atopic dermatitis through this review article.

Screening for Comorbid Cardiovascular Risk Factors in Pediatric Psoriasis Among Iraqi Patients: A Case-Control Study

Background: Psoriasis is a polygenic multifactorial immune-mediated skin disease associated with comorbidities. As one-third of adult psoriasis starts during childhood, early detection of these comorbidities might help to mitigate their impact on future health.

Objectives: To investigate the risk for cardiovascular events and their relationship with psoriasis severity among Iraqi children and adolescents.

Patients and methods: A prospective, case-control, cross-sectional study on 150 patients with psoriasis and 150 age and sex-matched individuals. The study was carried out at the Department of Dermatology/Basra Teaching Hospital from December 2018 to December 2020. Psoriasis severity was assessed by PASI (psoriasis area severity index) score, and in both groups, blood pressure and body mass index (BMI) were measured. Laboratory tests including fasting blood sugar (FBS) and lipid profile were also done.

Results: More patients were overweight and obese in the psoriatic group compared to the control group (26.7% and 40% versus 11% and 8%), 5.3% of psoriatic patients who had stage 2 hypertension (defined as any blood pressure [BP] measurement higher than 99^th plus 5 mm of mercury applied to BP levels for boys and girls by age and height percentile charts), none of the control group was hypertensive, and the difference was statistically significant (p-value<0.05). A significantly higher proportion of the psoriatic patients had abnormal lipid profiles compared with the control group, 62% versus 30% (p<0.05), 15.3% versus 6.7% had elevated cholesterol (p<0.05), 24.7% versus 8% had raised low-density lipoprotein (LDL, p<0.05), 18% versus 8.6% had low high-density lipoprotein (HDL, p<0.05), and 12.6% versus 6% had elevated very-low-density lipoprotein (VLDL) and triglyceride (TG, p<0.05), 8% patients had elevated FBS (more than 100 mg per deciliter) versus 2.6% (p<0.05), and metabolic syndrome in 65 versus 2% (p<0.05). These changes were related to the severity of psoriasis.

Conclusions: Pediatric psoriatic patients in our population may have an atherogenic lipid profile with an increased prevalence of risk factors for cardiovascular diseases, especially those with moderate to severe psoriasis.

The hair follicle-psoriasis axis: Shared regulatory mechanisms and therapeutic targets

It has long been known that there is a special affinity of psoriasis for the scalp: Here, it occurs most frequently, lesions terminate sharply in frontal skin beyond the hair line and are difficult to treat. Yet, surprisingly, scalp psoriasis only rarely causes alopecia, even though the pilosebaceous unit clearly is affected. Here, we systematically explore the peculiar, insufficiently investigated connection between psoriasis and growing (anagen) terminal scalp hair follicles (HFs), with emphasis on shared regulatory mechanism and therapeutic targets. Interestingly, several drugs and stressors that can trigger/aggravate psoriasis can inhibit hair growth (e.g. beta-blockers, chloroquine, carbamazepine, interferon-alpha, perceived stress). Instead, several anti-psoriatic agents can stimulate hair growth (e.g. cyclosporine, glucocorticoids, dithranol, UV irradiation), while skin/HF trauma (Köbner phenomenon/depilation) favours the development of psoriatic lesions and induces anagen in "quiescent" (telogen) HFs. On this basis, we propose two interconnected working models: (a) the existence of a bidirectional "hair follicle-psoriasis axis," along which keratinocytes of anagen scalp HFs secrete signals that favour the development and maintenance of psoriatic scalp lesions and respond to signals from these lesions, and (b) that anagen induction and psoriatic lesions share molecular "switch-on" mechanisms, which invite pharmacological targeting, once identified. Therefore, we advocate a novel, cross-fertilizing and integrative approach to psoriasis and hair research that systematically characterizes the "HF-psoriasis axis," focused on identification and therapeutic targeting of selected, shared signalling pathways in the future management of both, psoriasis and hair growth disorders.

Identifying the best predictive diagnostic criteria for psoriasis in children (< 18 years): a UK multicentre case-control diagnostic accuracy study (DIPSOC study)

BACKGROUND

In children, psoriasis can be challenging to diagnose. Difficulties arise from differences in the clinical presentation compared with adults.

OBJECTIVES

To test the diagnostic accuracy of previously agreed consensus criteria and to develop a shortlist of the best predictive diagnostic criteria for childhood psoriasis.

METHODS

A case-control diagnostic accuracy study in 12 UK dermatology departments (2017-2019) assessed 18 clinical criteria using blinded trained investigators. Children (< 18 years) with dermatologist-diagnosed psoriasis (cases, N = 170) or a different scaly inflammatory rash (controls, N = 160) were recruited. The best predictive criteria were identified using backward logistic regression, and internal validation was conducted using bootstrapping.

RESULTS

The sensitivity of the consensus-agreed criteria and consensus scoring algorithm was 84·6%, the specificity was 65·1% and the area under the curve (AUC) was 0·75. The seven diagnostic criteria that performed best were: (i) scale and erythema in the scalp involving the hairline, (ii) scaly erythema inside the external auditory meatus, (iii) persistent well-demarcated erythematous rash anywhere on the body, (iv) persistent erythema in the umbilicus, (v) scaly erythematous plaques on the extensor surfaces of the elbows and/or knees, (vi) well-demarcated erythematous rash in the napkin area involving the crural fold and (vii) family history of psoriasis. The sensitivity of the best predictive model was 76·8%, with specificity 72·7% and AUC 0·84. The c-statistic optimism-adjusted shrinkage factor was 0·012.

CONCLUSIONS

This study provides examination- and history-based data on the clinical features of psoriasis in children and proposes seven diagnostic criteria with good discriminatory ability in secondary-care patients. External validation is now needed.

So close, and yet so far away: The dichotomy of the specific immune response and inflammation in psoriasis and atopic dermatitis

Characterization of the complex interplay between cytokines, chemokines and microorganisms has led to a better understanding of the pathogenesis of both psoriasis and AD and resulted in new therapeutics targeting distinct immune responses. Psoriasis and AD share many characteristics: they are highly prevalent, chronic, cause primarily skin inflammation, but are associated with comorbidities, and come with a devastating quality of life due to itch and stigmatization. However, the pathogenesis of psoriasis and AD is opposing - psoriasis is dominated by a Th17 immune response that causes neutrophil migration, induction of innate immunity and exaggerated epithelial metabolism. Leading cytokines of this Th17 immune response are IL-17A and F, IL-22 and TNF-a. AD is characterized by Th2 immunity characterized by the signature cytokines IL-4 and IL-13 leading to an impaired epidermal barrier, dampened innate immunity and eosinophil migration. This review compares genetics, microbiome and T-cell infiltrate and resulting epithelial response in psoriasis and AD. Whilst the antagonistic course of psoriasis and AD is confirmed by response to specific biologics targeting the key cytokines of inflammation in psoriasis and AD, respectively, clinically overlapping phenotypes are challenging in our daily clinical practice. We conclude this review by summarizing what is known about these mixed phenotypes and how the identification of clinically relevant endotypes and molecular-driven decision-making is the next step in the field of dermato-immunology.

Bidirectional Association between Psoriasis and Atopic Dermatitis: A Nationwide Population-Based Cohort Study

BACKGROUND

There have been some reports on the coexistence of psoriasis and atopic dermatitis; however, the longitudinal relationship between these two diseases remains unclear.

OBJECTIVE

This study aimed to investigate the bidirectional association between psoriasis and atopic dermatitis.

METHODS

This cohort study recruited patients from the National Health Insurance Research Database in Taiwan. We included 8,206 patients with psoriasis and 32,824 matched controls to assess the risk of atopic dermatitis and 25,743 patients with atopic dermatitis and 102,972 matched controls to assess the risk of psoriasis. Cox regression model was used for the analyses.

RESULTS

After adjusting for potential confounders, patients with psoriasis had a higher risk of atopic dermatitis (adjusted hazard ratio [aHR] 13.01; 95% CI 10.23-16.56) than the controls. Patients with atopic dermatitis had a higher risk of psoriasis (aHR 10.37; 95% CI 6.85-15.69) than the controls. Stratified analyses revealed similar results in both sexes and all age groups.

CONCLUSION

Our study demonstrated a bidirectional association between psoriasis and atopic dermatitis, suggesting that psoriasis and atopic dermatitis are not mutually exclusive and may share some biological mechanisms.

Atopic Dermatitis and Psoriasis as Overlapping Syndromes

Methods

In this observational study, 38 children with concomitant AD and PS with a mean age of 6.5 ± 3.2 yrs were compared with 41 similar patients with AD only (5.3 ± 5.1 yrs) and 28 patients with PS only (6.4 ± 4.3 yrs). All patients underwent dermatological examinations, including determination of SCORAD and PASI scores. TNF-α, IFN-γ, IL-2, IL-4, IL-5, IL-6, IL-8, IL-12, IL-17, IL-18, IL-22, I:-33, and TARC/CCL17 were measured by ELISA according to the manufacturer's instructions.

Results

Patients with concomitant AD and PS were frequently boys and overweight and had skin lesions equally distributed throughout the body. Children with concomitant AD and PS were more likely to report a family history of atopic disease than children with only AD or PS, and those with AD were more likely to report a family history of atopic disease than those with PS. Significant differences were observed in the concentration of IL-17 between patients with AD and PS and those with only AD or PS: 9.1 ± 3.7 pg/ml vs. 4.8 ± 2.9 pg/ml; and 9.1 ± 3.7 pg/ml vs. 5.2 ± 3.9 pg/ml, respectively (PD vs. AD, p = 0.01; PD vs. PS, p = 0.03).

Conclusions

AD and PS can coexist. The role of T helper 17 cells may be more essential than believed.

Real-world evaluation of "Eczema in psoriatico": Bridging the gap between dermatology and dermatopathology

The diagnosis of psoriasis is mainly made by clinical examination but on some occasions according to the localization or duration of the lesions when spongiosis is more prominent, it can be challenging and may be considered as overlapping eczema. To evaluate the patients for "eczema in psoriatico" and to present the differences between psoriasis. Biopsy outcomes of thirty-one patients who were histologically diagnosed with psoriasis and psoriasiform dermatitis because of the erythematous and scaly plaque lesions located on hands and feet, between 2013 and 2015, were evaluated retrospectively. Histopathologic findings compatible with psoriasis and accompanied by spongiosis and spongiotic vesicles were evaluated as eczema in psoriatico and compared with psoriasis. In this study thirty-one patients, including 18 patients with eczema in psoriatico and 13 patients with psoriasis of hands and/or feet were included. Of the 31 patients, 15 (48.4%) were women and 16 (51.6%) were men, in 61.3% of cases, biopsies were taken from hands (61.1% of "eczema in psoriatico", 61.5% of psoriasis) and 38.7% from feet (38.9% of "eczema in psoriatico", 38.5% of psoriasis). There was a statistically significant difference between two groups in terms of parakeratosis severity and distribution, the presence of neutrophil and plasma in stratum corneum, the presence of granular layer loss and suprapapillar plate thinning, the shape of retes, the presence of lymphocytic exocytosis, spongiosis and spongiotic vesicles, the intensity of infiltrates in the papillar dermis and the presence of dermal edema (P < .05). Histology supports a continuum between psoriasis and eczema that share histological similarities and at the same time should be considered a separate entity, eczema in psoriatico.

Psoriasis is Associated with a High Comedication Burden: A Population Based Register Study

Introduction

A large body of evidence supports the association between psoriasis and concomitant diseases. However, the study of comedication for these diseases in patients with psoriasis is limited. The current study aimed to investigate the prescription and drug dispensation for comorbidity associated with psoriasis.

Methods

We conducted a retrospective case-control study from 9 April 2008 until 1 January 2016 using an electronic medical records database covering the entire population of the County of Jönköping and the Swedish Prescribed Drug Register. ICD-10 and Anatomical Therapeutic Chemical codes were used to identify patients with psoriasis and dispensed pharmaceutical prescriptions. Individuals without psoriasis were selected as controls. Patients receiving systemic treatment for psoriasis were considered as having moderate-severe psoriasis. Odds ratios for being dispensed pharmaceutical prescriptions and differences in mean number of dispensed prescriptions were explored.

Results

A total of 4587 patients with psoriasis were identified in the medical records, and 268,949 individuals served as controls. Patients with psoriasis had a significantly higher number of different drug dispensations compared to controls. Only 1.3% of all patients with psoriasis were without any prescription (excluding medication for psoriasis) during the study period while the number in the general population was 9.3%. Sex- and age-adjusted odds ratios for dispensation of drug groups related to comorbid disease were significantly higher among patients with psoriasis including drug groups such as anxiolytics and sedatives as well as drugs targeting COPD, migraine and erectile dysfunction. The most frequently dispensed comedications were oral antibiotics and analgesics including an increased risk for dispensation of opioids. Sex predisposed dispensation frequency for a variety of drug groups. Drugs targeting obesity, osteoporosis, psychiatric disease and anti-mycotics/-fungals were more frequent among women.

Conclusion

Patients with psoriasis have significantly increased numbers of different dispensed prescriptions than those without psoriasis. This underlines previous findings on increased comorbidity and health care costs for patients with psoriasis.

Electronic supplementary material

The online version of this article (10.1007/s13555-020-00442-3) contains supplementary material, which is available to authorized users.

Shades of grey: what is paediatric psoriasiform dermatitis and what does it have in common with childhood psoriasis?

BACKGROUND

While the majority of children with a chronic itchy rash suffer from atopic dermatitis (AD) and other forms of dermatitis, psoriasis is in the differential diagnosis. Certain patterns such as guttate and napkin psoriasis are accepted as classic paediatric psoriasis (PP); however, there are many patients who do not fit these classic forms of PP nor fulfil the accepted criteria for AD. 'Psoriasiform dermatitis' (PD) is a term that has been used for these patients; however, it has not been formally defined. Identification of this group of patients, who although not having the typical clinical features of psoriasis, respond well to psoriasis-specific treatment, may assist treatment decisions for these patients.

AIM

To describe PD and compare it with typical PP.

METHODS

Patients with classic PP (n = 109) were compared with a control group with AD (n = 449) and assessed for 21 clinical features associated with PP. Multivariate nonlinear regression analyses determined which features best separated the groups. Patients with dermatitis who demonstrated any of these 21 features (n = 43), which were used to diagnose PD, were then compared with the PP and AD groups. They were managed with psoriasis-specific treatment and Psoriasis Area and Severity Index (PASI) was recorded.

RESULTS

Of the 21 clinical features, 12 were found to clearly separate the classic PP and AD groups. Using the eight most significant (P < 0.0001) features, we found these two groups clearly separated at a score of 3 out of 8. Children with PD with ≥ 4 of these features responded well to treatment for psoriasis with a mean reduction of PASI by 85% at 6 weeks.

CONCLUSIONS

We found that patients with dermatitis who have ≥ 4 psoriasis-associated features may have a condition that has been previously alluded to but not defined in the literature, 'psoriasiform dermatitis'. Treatments usually reserved for patients with psoriasis appear to be effective in these patients.

Protocol for a case-control diagnostic accuracy study to develop diagnostic criteria for psoriasis in children (DIPSOC study): a multicentre study recruiting in UK paediatric dermatology clinics

INTRODUCTION

Diagnosing psoriasis in children can be challenging. Early and accurate diagnosis is important to ensure patients receive psoriasis specific treatment and monitoring. It is recognised that the physical, psychological, quality of life, financial and comorbid burden of psoriasis are significant. The aim of this study is to develop clinical examination and history-based diagnostic criteria for psoriasis in children to help differentiate psoriasis from other scaly inflammatory rashes. The criteria tested in this study were developed through a consensus study with a group of international psoriasis experts (International Psoriasis Council).

METHODS AND ANALYSIS

Children and young people (<18 years) with psoriasis (cases) and other scaly inflammatory skin diseases (controls) diagnosed by a dermatologist are eligible for recruitment. All participants complete a single research visit including a diagnostic criteria assessment by a trained investigator blinded to the participant's diagnosis. The reference standard of a dermatologist's diagnosis is extracted from the medical record. Sensitivity and specificity of the consensus derived diagnostic criteria will be calculated and the best predictive criteria developed using multivariate logistic regression.

ETHICS AND DISSEMINATION

Health Regulatory Authority and National Health Service Research Ethics Committee approvals were granted in February 2017 (REC Ref: 17/EM/0035). Dissemination will be guided by stakeholders; patients, children and young people, dermatologists, primary care and paediatric rheumatologists. The aim is to publish the study results in a high-quality peer-reviewed journal, present the findings at international academic meetings and disseminate more widely through social media and working with patient associations.

TRIAL REGISTRATION NUMBER

ISRCTN98851260.

A systematic review and meta-analysis of the regional and age-related differences in atopic dermatitis clinical characteristics

BACKGROUND

Previous studies found conflicting results about the commonality of different atopic dermatitis (AD) signs and symptoms.

OBJECTIVE

To determine the prevalences of AD characteristics and differences by region and age.

METHODS

A systematic review was performed of all published studies in MEDLINE, EMBASE, SCOPUS, LILACS, Cochrane, China National Knowledge Infrastructure, Taiwan Electronic Periodical Services, and CiNii that analyzed the proportion of AD characteristics. Two reviewers performed a review study titles and/or abstracts and data abstraction.

RESULTS

In all, 101 studies reported proportion of AD features with sufficient data for meta-analysis. The most prevalent AD features were pruritus, lichenification, and xerosis. There were differences in AD characteristics by study region. Flexural involvement was less commonly reported in India, the Americas, and Iran. Studies from East Asian reported more erythroderma and truncal, extensor, scalp, and auricular involvement. Studies from Southeast Asia reported more exudative eczema, truncal involvement, lichenification, and prurigo nodularis. Studies from Iran reported more head, face, and neck involvement; pityriasis alba; and xerosis. Studies from Africa reported more papular lichenoid lesions, palmar hyperlinearity, ichthyosis, and orbital darkening.

LIMITATIONS

Heterogeneity between studies and limited reporting of certain AD clinical characteristics.

CONCLUSIONS

AD characteristics are heterogeneous and vary by region and age.

Typical and atypical clinical appearance of atopic dermatitis

Atopic dermatitis is a complex, systemic inflammatory disorder associated with a variety of clinical features. The original criteria of Hanifin and Rajka include major criteria and a list of about two dozen minor criteria however, even the minor criteria do not include some features of atopic dermatitis noted less commonly but still seen with some frequency. This contribution first reviews the common clinical appearance of atopic dermatitis in infancy, childhood, and adulthood, as well as the less typical appearances, including lichenoid atopic dermatitis; juvenile plantar dermatosis; nummular-type atopic dermatitis; follicular atopic dermatitis; alopecia of atopic dermatitis; eczema coxsackium; and psoriasiform, perineal, and lip licker's dermatitis. The clinician will be able to recognize and treat rarer forms of atopic dermatitis and incorporate this into their daily practice.

Diagnosis of Atopic Dermatitis: Mimics, Overlaps, and Complications

Atopic dermatitis (AD) is one of the most common skin diseases affecting infants and children. A smaller subset of adults has persistent or new-onset AD. AD is characterized by pruritus, erythema, induration, and scale, but these features are also typical of several other conditions that can mimic, coexist with, or complicate AD. These include inflammatory skin conditions, infections, infestations, malignancies, genetic disorders, immunodeficiency disorders, nutritional disorders, graft-versus-host disease, and drug eruptions. Familiarity of the spectrum of these diseases and their distinguishing features is critical for correct and timely diagnosis and optimal treatment.

Genome-wide comparative analysis of atopic dermatitis and psoriasis gives insight into opposing genetic mechanisms

Atopic dermatitis and psoriasis are the two most common immune-mediated inflammatory disorders affecting the skin. Genome-wide studies demonstrate a high degree of genetic overlap, but these diseases have mutually exclusive clinical phenotypes and opposing immune mechanisms. Despite their prevalence, atopic dermatitis and psoriasis very rarely co-occur within one individual. By utilizing genome-wide association study and ImmunoChip data from >19,000 individuals and methodologies developed from meta-analysis, we have identified opposing risk alleles at shared loci as well as independent disease-specific loci within the epidermal differentiation complex (chromosome 1q21.3), the Th2 locus control region (chromosome 5q31.1), and the major histocompatibility complex (chromosome 6p21-22). We further identified previously unreported pleiotropic alleles with opposing effects on atopic dermatitis and psoriasis risk in PRKRA and ANXA6/TNIP1. In contrast, there was no evidence for shared loci with effects operating in the same direction on both diseases. Our results show that atopic dermatitis and psoriasis have distinct genetic mechanisms with opposing effects in shared pathways influencing epidermal differentiation and immune response. The statistical analysis methods developed in the conduct of this study have produced additional insight from previously published data sets. The approach is likely to be applicable to the investigation of the genetic basis of other complex traits with overlapping and distinct clinical features.