Clinical and epidemiological comparison of patients affected by palmoplantar plaque psoriasis and palmoplantar pustulosis: a case series study

Health-related quality of life in patients with palmoplantar pustulosis - a Swedish register study

BACKGROUND

Real-world data on health-related quality of life (HRQoL) in palmoplantar pustulosis (PPP) are scarce and few studies have analysed the generic HRQoL.

OBJECTIVES

To assess HRQoL using the generic EQ-5D instrument and the Dermatology Life Quality Index (DLQI) instrument in PPP compared to plaque psoriasis.

METHODS

Cross-sectional data from PsoReg, the Swedish National Registry for Systemic Treatment of Psoriasis (2006-2021), were examined. The study included 306 patients with PPP, out of which 22% had concomitant plaque psoriasis (n = 68), and 7041 patients with plaque psoriasis only. EQ-5D and DLQI were compared between patients with PPP and patients with plaque psoriasis, overall and stratified by sex. A subgroup analysis compared outcomes for patients with PPP vs. patients with severe plaque psoriasis (Psoriasis Area and Severity Index ≥10). Multiple regression analyses were performed to control for potential confounders (age, sex, comorbidities, lifestyle factors).

RESULTS

Patients with PPP were to a larger extent female (79% vs. 37%, p < .01) and older (mean [SD] age 59.9 [11.9] vs. 50.7 [16.0] years, p < .01) than patients with plaque psoriasis. EQ-5D values were significantly lower (worse) in patients with PPP (mean [SD] 0.622 [0.309]) compared to patients with plaque psoriasis (mean [SD] 0.715 [0.274]). No significant difference was observed compared to patients with severe plaque psoriasis (p = .237). DLQI was comparable in PPP and plaque psoriasis patients (p = .117). In the regression analyses, PPP only and PPP with plaque psoriasis were associated with lower EQ-5D values of 0.065 (p < .01) and 0.061 points (p < .10) compared to plaque psoriasis patients.

CONCLUSIONS

PPP had a substantial negative impact on patients' generic and dermatology-specific HRQoL. Patients with PPP were worse off in terms of generic HRQoL compared with patients with plaque psoriasis when controlling for the impact of potential confounders.

[Palmoplantar dermatoses: Diagnostic approach in primary care]

This article addresses the diagnostic challenges of palmoplantar dermatoses (PPD) within the scope of Primary Health Care (PHC). These common skin conditions, encountered in daily practice, exhibit a diverse range of symptoms and morphologies, complicating their diagnosis. They are etiologically classified into infectious inflammatory, non-infectious inflammatory, and hereditary keratodermas. While various dermatoses may affect the palms and soles, few are specific to this area. Notable examples include palmoplantar pustulosis, dyshidrosis, erythema pernio, and Bazex syndrome. Given the high prevalence of dermatological consultations in PHC, this article underscores the significance of PHC professionals' knowledge regarding these conditions. It proposes a diagnostic algorithm to facilitate their management and timely referral.

Synovitis, Acne, Pustulosis, Hyperostosis, Osteitis, Palmoplantar Pustulosis, and Neutrophilic Dermatoses: A GRAPPA 2023 Annual Meeting Update

Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome and chronic nonbacterial osteomyelitis (CNO) are rare autoinflammatory/autoimmune conditions seen in adults and children. Although osteoarticular manifestations are the primary distinguishing features of SAPHO, over half of patients also have palmoplantar pustulosis (PPP). These and other associated disorders such as acne, inflammatory bowel disease, and hidradenitis suppurativa are characterized, at least in the early stages, by neutrophilic infiltration. The bone and skin manifestations exhibit both innate and adaptive immune responses and therefore share similar pathogenic molecules and overlapping treatment targets. At the Group for Research and Assessment for Psoriasis and Psoriatic Arthritis (GRAPPA) 2023 annual meeting, a 3-part presentation provided an overview of current efforts at establishing consensus on diagnosis/classification, treatment, and core outcome sets for SAPHO/CNO; an overview of PPP in SAPHO and as a standalone condition; and finally, an overview of the role of the neutrophil in these disorders.

Efficacy and Safety of Brodalumab, an Anti-interleukin-17 Receptor A Monoclonal Antibody, for Palmoplantar Pustulosis: 16-Week Results of a Randomized Clinical Trial

BACKGROUND

Palmoplantar pustulosis (PPP), a refractory skin disease characterized by repeated eruptions of sterile pustules and vesicles on palms and/or soles, involves interleukin-17 pathway activation. Brodalumab, a fully human anti-interleukin-17 receptor A monoclonal antibody, is being investigated for use in PPP treatment.

OBJECTIVE

The aim was to assess the efficacy and safety of brodalumab in Japanese PPP patients with moderate or severe pustules/vesicles.

METHODS

A phase 3, randomized, double-blind, placebo-controlled trial was conducted between July 2019 and August 2022, at 41 centers in Japan. Patients aged 18-70 years with a diagnosis of PPP for ≥ 24 weeks, a PPP Area Severity Index (PPPASI) score of ≥ 12, a PPPASI subscore of pustules/vesicles of ≥ 2, and inadequate response to therapy were included. Participants were randomized 1:1 to receive brodalumab 210 mg or placebo, subcutaneously (SC) at baseline, weeks 1 and 2, and every 2 weeks (Q2W) thereafter until week 16. Changes from baseline to week 16 in the PPPASI total score (primary endpoint) and other secondary skin-related endpoints and safety endpoints were assessed.

RESULTS

Of the 126 randomized patients, 50 of 63 in the brodalumab group and 62 of 63 in the placebo group completed the 16-week period. Reasons for discontinuation were adverse event (n = 6), withdrawal by patient/parent/guardian (n = 3), progressive disease (n = 3), and lost to follow-up (n = 1) in the brodalumab group and Good Clinical Practice deviation (n = 1) in the placebo group. Change from baseline in the PPPASI total score at week 16 was significantly higher (p = 0.0049) with brodalumab (least-squares mean [95% confidence interval {CI}] 13.73 [10.91-16.56]) versus placebo (8.45 [5.76-11.13]; difference [95% CI] 5.29 [1.64-8.94]). At week 16, brodalumab showed a trend of rapid improvement versus placebo for PPPASI-50/75/90 response (≥ 50%/75%/90% improvement from baseline) and Physician's Global Assessment 0/1 score: 54% versus 24.2%, 36.0% versus 8.1%, 16.0% versus 0.0%, and 32.0% versus 9.7%, respectively. Infection was the dominant treatment-emergent adverse event (TEAE); the commonly reported TEAEs were otitis externa (25.4%/1.6%), folliculitis (15.9%/3.2%), nasopharyngitis (14.3%/4.8%), and eczema (14.3%/12.9%) in the brodalumab/placebo groups, respectively. The severity of most TEAEs reported was Grade 1 or 2 and less frequently Grade ≥ 3.

CONCLUSIONS

Brodalumab SC 210 mg Q2W demonstrated efficacy in Japanese PPP patients. The most common TEAEs were mild infectious events.

TRIAL REGISTRATION

NCT04061252 (Date of Trial Registration: August 19, 2019).

Palmoplantar psoriasis: A clinicopathological correlation in a tertiary care hospital

BACKGROUND

Palmoplantar psoriasis is a clinical variant of psoriasis characterized by well-defined erythematous desquamating plaques on palms and soles, which may or may not include pustules. Hyperkeratotic lesions of palm and sole commonly include Psoriasis, Eczema and Tinea. These conditions often present with overlapping clinical and histopathological features requiring clinicohistopathological correlation for a conclusive diagnosis. The presence of munro's microabscess or spongiform pustule of kogoj differentiates psoriasis of palm and sole from other hyperkeratotic lesions of palm and sole. The objective of this study was to study the clinical and histopathological profile of palmoplantar psoriasis and correlate clinical diagnosis with histopathological diagnosis.

METHOD

A hospital-based, descriptive study was conducted from January 1, 2020, to December 31, 2020. Fifty-two patients were clinically diagnosed as palmoplantar psoriasis with or without involving other parts of body and routine histopathological evaluation was carried out as per standard protocols.

RESULT

Clinically diagnosed 52 cases of palmoplantar psoriasis showed varied histopathology with hyperkeratosis (100%), parakeratosis (100%), regular acanthosis (75%), Supra-papillary thinning (44.2%), spongiosis (65.4%), tortuous vessels in the papillary dermis (78.8%) and mixed inflammatory infiltrates (predominantly lymphocytic-100%), which were observed to be prominent findings in skin biopsies of our patients. Clinicopathological correlation was achieved in 88.5% of cases.

CONCLUSION

This study shows clinically diagnosed palmoplantar psoriasis with histopathological features consistent with palmoplantar psoriasis in 88.5% cases. Thus, clinically inconclusive hyperkeratotic lesions with palmoplantar psoriasis can be diagnosed with histopathological correlation improving the therapeutic intervention.

Small-Molecule Inhibitors and Biologics for Palmoplantar Psoriasis and Palmoplantar Pustulosis: A Systematic Review and Network Meta-Analysis

BACKGROUND

The comparative efficacy of biologics and small-molecule inhibitors in treating palmoplantar psoriasis (PP) and palmoplantar pustulosis (PPP) remains uncertain.

OBJECTIVE

The aim was to perform a systematic review and network meta-analysis (NMA) to compare the efficacy of biologics and small-molecule inhibitors for the treatment of PP and PPP.

METHODS

MEDLINE, Embase, and Cochrane Central Register of Controlled Trials were searched for eligible studies from inception to May 13, 2023. This NMA was conducted and reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension Statement for Network Meta-Analyses guidelines. Frequentist random-effects models NMA was performed with the surface under the cumulative ranking curve calculated for ranking. Our primary outcome was the proportion of patients achieving a clear/minimal Palmoplantar Psoriasis/Pustulosis Physician Global Assessment score (PPPGA 0/1 or PPPPGA 0/1) response at 12-16 weeks. Secondary outcomes consisted of the percentage of overall improvement in palmoplantar score and of improvement ≥ 75%, at 12-16 weeks.

RESULTS

The study comprised a total of 29 randomized controlled trials (RCTs), involving 4798 psoriasis patients with palmoplantar diseases. For PP, 16 RCTs with nine different treatments, including adalimumab, apremilast, bimekizumab, etanercept, guselkumab, infliximab, ixekizumab, secukinumab, and ustekinumab were included for the analysis. In the NMA of PP, secukinumab 300 mg ranked highest (odds ratio [OR] 33.50, 95% confidence interval [CI] 4.37-256.86) in achieving PPPGA 0/1, followed by guselkumab 100 mg (OR 18.68, 95% CI 10.07-34.65). In the case of PPP, seven RCTs with six treatments, including apremilast, etanercept, guselkumab, imsidolimab, spesolimab, and ustekinumab, were included for the analysis. In the NMA of PPP, although no treatment demonstrated a significant difference compared to placebo in achieving PPPPGA 0/1, guselkumab 100 mg showed the greatest statistically significant improvement in the palmoplantar score (weighted mean difference 31.73, 95% CI 19.89-43.57) as a secondary outcome.

CONCLUSION

Among all available biologics and small-molecule inhibitors, secukinumab 300 mg and guselkumab 100 mg had the most favorable efficacy in treating PP and PPP, respectively.

A retrospective analysis of 65 patients with acrodermatitis continua of Hallopeau

There are limited data on acrodermatitis continua of Hallopeau (ACH), particularly among Asian populations. The primary aim was to evaluate the clinical features of ACH and treatment approaches in a sizeable multicentre Asian cohort. We analysed data from adult patients diagnosed with ACH. Of 65 patients with ACH, seven patients had ACH with GPP. Females were more frequently affected in both conditions. Five (71.4%) developed GPP 5-33 years after ACH onset, while two (28.6%) developed GPP concurrently with ACH. The onset age for ACH with GPP (27.9 ± 13.6 years) was earlier than that of isolated ACH (39.8 ± 17.3 years). Metabolic comorbidities were common. ACH exhibited a chronic persistent course. Among systemic non-biologics, acitretin was the most frequently prescribed, followed by ciclosporin and methotrexate. Acitretin and ciclosporin demonstrated similar marked response rates, which surpassed that of methotrexate. Regarding biologics, a marked response was more commonly observed with interleukin-17 inhibitors than with tumour necrosis factor inhibitors. Females are predominant in both conditions. The onset age for ACH among Asian patients is earlier (late 30s) than that for Caucasian patients (late 40s). Interleukin-17 inhibitors may be more effective than tumour necrosis factor inhibitors in managing ACH.

Downregulation of Caveolae-Associated Proteins in Psoriasis: A Case Series Study

We have previously identified that a structural membrane protein Caveolin-1 (Cav1) is involved in the regulation of aberrant keratinocyte proliferation and differentiation. The aim of this study was to elucidate the role of Cav1, Caveolin-2 (Cav2), and Cavin-1 in the pathogenesis of psoriasis vulgaris and between psoriasis subtypes. We utilized human biopsies from validated cases of psoriasis vulgaris (n = 21) at the University of Miami Hospital and compared the expression of Cav1, Cav2, and Cavin-1 by immunohistochemistry staining with that in normal healthy age-/sex-/location-matched skin (n = 15) and chronic spongiotic dermatitis skin samples (as control inflammatory skin condition) and quantified using QuPath. Distinct subtypes of psoriasis included guttate, inverse, nail, plaque, palmoplantar, and pustular. All biopsy samples exhibited a trend toward downregulation of Cav1, with nail, plaque, and palmoplantar psoriasis exhibiting the most pronounced effects. Only nail and pustular psoriasis samples exhibited significant downregulation of Cav2 and Cavin-1, suggesting Cav1 to be the main caveolar contributor to the pathogenesis of psoriasis. Together, these data support caveolae as pathophysiological targets in nail and pustular psoriasis, whereas Cav1 seems to be a general biomarker of multiple subtypes of psoriasis.

Treatment Patterns and Negative Health Outcomes in Palmoplantar Pustulosis Patients in Germany and the US

INTRODUCTION

Limited information exists on the epidemiology, treatment, and burden of palmoplantar pustulosis (PPP) and defining the optimal course of treatment remains challenging without approved targeted treatments in most countries. Here, we describe the clinical and demographic characteristics, treatments received, and negative health outcomes experienced among patients with PPP in the United States (US) and Germany.

METHODS

Retrospective cohort study between 2016 and 2021 using data from the US Merative™ MarketScan® Research Database and IQVIA™ German Disease Analyzer. Adult patients with PPP (ICD-10-CM L40.3) were followed from the date of their first qualifying PPP diagnosis and continued until the earlier of disenrollment or end date of database, during which treatment patterns and incidence rates of negative health outcomes were assessed. Treatment patterns included adherence, non-persistence, discontinuation, re-initiation, switching, and combination therapy.

RESULTS

The prevalence of PPP was 0.005% and 0.065% in the MarketScan database and German Disease Analyzer, respectively, with 1629 and 3866 patients meeting the inclusion criteria. Most patients were female (71.3%, 67.8%), with mean (SD) age of 54.1 (11.7) and 56.9 (14.3) years, respectively. One year post index, most patients received topical treatment (77.4%, 65.3%), but non-persistence and discontinuation were high. Oral and biologic treatments displayed higher levels of adherence, particularly apremilast and tofacitinib among oral treatments and TNF inhibitors and IL-23 inhibitors among biologics. Rates of negative health outcomes were higher among patients not receiving treatment post-index compared with those receiving treatment post-index across both databases, regardless of prior treatment history.

CONCLUSIONS

Establishing treatment guidelines remains an unmet need for patients with PPP and could improve quality of life by reducing the occurrence of negative health outcomes. The findings from this study may provide insight into the effectiveness of current treatment options for patients with PPP and can be leveraged to support the development of treatment guidelines.

Pustular psoriasis: A distinct aetiopathogenic and clinical entity

Pustular psoriasis is a distinct subset of psoriasis that presents with involvement of the skin in the form of sterile pustules along with systemic manifestations. Though it has been conventionally grouped under the umbrella of psoriasis, recent research has shed light on its pathogenetic mechanisms associated with the IL-36 pathway, which is distinct from conventional psoriasis. Pustular psoriasis in itself is a heterogeneous entity consisting of various subtypes, including generalised, localised, acute, and chronic forms. There is confusion regarding its current classification as entities like deficiency of IL-36 antagonist (DITRA) which are closely related to pustular psoriasis both in their pathogenetic mechanism and its clinical manifestations, are not included under pustular psoriasis. Entities like palmoplantar pustulosis, which presents with similar clinical features but is pathogenetically distinct from other forms of pustular psoriasis, are included under this condition. Management of pustular psoriasis depends upon its severity; while some of the localised variants can be managed with topical therapy alone, the generalised variants like Von Zumbusch disease and impetigo herpetiformis may need intensive care unit admission and tailor-made treatment protocols. The advent of newer biologics and better insight into the pathogenesis of pustular psoriasis has opened the way for newer therapies, including tumour necrosis factor-alpha inhibitors, interleukin-1 inhibitors, interleukin-17 inhibitors, and granulocyte monocyte apheresis. It continues to be an enigma whether pustular psoriasis is actually a variant of psoriasis or an entirely different disease entity, though we feel that it is an entirely different disease process.

Drug survival of biologics and non-biologics in patients affected by palmoplantar psoriasis: a "real-world", mono-center experience

BACKGROUND

Data on the treatment of palmoplantar psoriasis (PP) are very limited as these patients are often excluded from clinical trials. Moreover, this form of psoriasis is often resistant to treatment, making its clinical management complex.

METHODS

Primary endpoint was to evaluate the clinical and demographic characteristics and the drug survival of both biological and non-biological drugs in a population affected by PP. Secondary endpoint was to highlight any differences between the hyperkeratotic and pustular variant. We analyzed data from 233 psoriasis patients with palmoplantar involvement, with or without chronic plaque psoriasis. We performed a drug-survival analysis with the aid of Kaplan-Meier survival and a multivariate analysis to highlight the influence of certain variables on treatment persistence using a Cox regression model.

RESULTS

The drug-survival analysis revealed that biologic drugs compared to non-biologic drugs are associated with a higher persistence in treatment (59.73 vs. 43.56%); in particular, anti-IL23 drugs were found to be the drugs with the best drug-survival overall (67.94% of patients at 60 months are still on these drugs). Furthermore, our multivariate analysis shows that when compared with biological drugs, non-biological drugs are associated with an increased risk of treatment discontinuation (HR = 1.95 [95% CI: 1.41-2.68], P = 0.001).

CONCLUSIONS

Our study confirms the difficulty of treating PP and shows that biologic drugs are associated with longer persistence in treatment than non-biologics in both PP's variants, not because of their higher effectiveness but because of their better safety profile.

Gender perspective in psoriasis: a scoping review and proposal of strategies for improved clinical practice by European dermatologists

Background

The prevalence of psoriasis is similar between men and women; however, evidence exists of sex- and gender-related differences in disease expression, impact, coping, and needs of patients with psoriasis. These differences are essential and should be considered in clinical practice and research.

Objective

To compile available evidence on sex- and gender-related differences in psoriasis, identify the most critical gaps in clinical practice and research, and use it to propose strategies for improved clinical practice.

Methods

Six European dermatologists selected the topics to consider according to their relevance in the dermatology setting with the support of methodologists. Evidence on sex- and gender-related differences was obtained by a scoping review based on search strategies in Medline and Cochrane Library from inception to October 2021 using the following terms: arthritis, psoriatic, psoriasis, gender, and sex. The panel discussed the results and proposed strategies by consensus.

Results

The scoping review identified broad themes: (1) clinical expression, (2) severity and patient-reported outcomes, (3) psychosocial impact, (4) access to treatments and propensity to treat, (5) comorbidities, and (6) treatment effect. The strategies are based on these broad themes.

Limitations

No risk of bias assessment was done due to the scoping nature of the review.

Conclusion

This review offers insights into gender differences in psoriasis, providing a foundation for improving clinical practice and patient outcomes.

Characteristics and Burdens of Disease in Patients from Beijing with Generalized Pustular Psoriasis and Palmoplantar Pustulosis: Multicenter Retrospective Cohort Study Using a Regional Database

BACKGROUND AND OBJECTIVE

Pustular psoriasis is a chronic and recurrent autoimmune disease, although little is known about the disease burden of pustular psoriasis in China. We analyzed the characteristics and disease burdens of patients from Beijing who had generalized pustular psoriasis (GPP) or palmoplantar pustulosis (PPP).

METHODS

This multicenter retrospective cohort study used a regional electronic health database that covered 30 public hospitals in Beijing. From June 2016 to June 2021, all patients with a diagnosis of GPP, PPP, or psoriasis vulgaris (PV) were identified by International Statistical Classification of Diseases and Related Health Problems, 10th Revision codes. The GPP and PPP cohorts were separately matched with patients with PV in a 3:1 ratio for comparisons. Demographic data, clinical characteristics, healthcare resource utilization, and costs were collected. Descriptive and comparative analyses were used to compare the cohorts.

RESULTS

There were 744 patients with GPP (46.8% men; age 42.14 ± 21.47 years) and 4808 patients with PPP (35.5% men; age 51.65 ± 16.12 years); 14.5% of patients with GPP had concomitant PV and 7.5% of patients with PPP had concomitant PV. Relative to matched patients with PV, patients with GPP had a higher prevalence of erythrodermic psoriasis (5.9% vs 0.4%, p < 0.0001), psoriatic arthritis (3.1% vs 1.5%, p = 0.007), and organ failure (1.1% vs 0.2%, p = 0.002). Relative to matched patients with PV, patients with PPP had a higher prevalence of cerebrovascular disease (4.7% vs 1.2%, p < 0.0001), thyroid dysfunction (3.9% vs 3.3%, p = 0.035), and type 2 diabetes mellitus (6.8% vs 5.9%, p = 0.030). More patients with GPP than patients with PV received systemic non-biological agents (27.9% vs 3.3%, p < 0.0001) and biologic agents (4.8% vs 2.0%, p = 0.010). More patients with PPP than patients with PV received topical agents (50.9% vs 34.7%, p < 0.0001) and systemic non-biological agents (17.8% vs 2.7%, p < 0.0001). More patients with GPP than patients with PV required inpatient hospitalization (22.0% vs 7.8%, p < 0.0001). Hospitalization stay was longer in patients with GPP than patients with PV (11.72 ± 0.45 vs 10.38 ± 0.45 days, p = 0.022). More patients with PPP than patients with PV had emergency visits (16.3% vs 12.8%, p < 0.0001). The GPP and PPP cohorts and their matched PV cohorts had no significant differences in costs. However, patients with PPP had lower outpatient costs than patients with PV (368.20 ± 8.19 vs 445.38 ± 5.90 Chinese Yuan per patient per month, p < 0.0001).

CONCLUSIONS

Patients from Beijing with GPP and PPP had higher disease burdens than matched PV cohorts, including the prevalence of comorbidities, healthcare resource utilization, and medication burden. However, the economic burden of pustular psoriasis was similar to that of PV. Practical and specific therapies are needed to reduce the burdens of pustular psoriasis.

Efficacy of biologic agents for palmoplantar psoriasis: a systematic review and network meta-analysis

BACKGROUND

Palmoplantar psoriasis (PP) represents a localized type of disease. While controversy over its' classification exists, a hyperkeratotic type, a pustular type and palmoplantar pustulosis (PPP) have been recognized. PP management is regularly supported by biologic agents. Our study aimed to review and synthesize available data regarding the efficacy of approved biologics for PP and PPP.

RESEARCH DESIGN AND METHODS

A literature search was conducted in PubMed, CENTRAL, Scopus, and ClinicalTrilas.gov. Utilizing random-effects inverse-variance frequentist network meta-analyses (NMAs), we ranked interventions. The proportion of participants with cleared skin was the primary outcome. Fifty and 75% improvement in palmoplantar psoriasis area severity index (PPASI) were also explored (PPASI50, PPASI75).

RESULTS

In total, 15 randomized controlled trials (RCTs) exploring the efficacy of on-label adalimumab, bimekizumab, etanercept, guselkumab, infliximab, ixekizumab, secukinumab, and ustekinumab were included. Data for PP were synthesized. Every biologic agent examined, except from infliximab, outperformed placebo. On-label secukinumab exhibited the highest probability of inducing complete resolution. Ixekizumab and infliximab ranked best on inducing PPASI50 and PPASI75. Our review supports that guselkumab is effective for PPP.

CONCLUSIONS

Secukinumab, ixekizumab and infliximab are effective for PP. Research is warranted to produce evidence about the efficacy of biologics in PP and PPP.

An update on therapeutic options for palmoplantar pustulosis: a narrative review and expert recommendations

INTRODUCTION

Palmoplantar pustulosis (PPP) is a chronic inflammatory skin disease belonging to the localized form of pustular psoriasis. It is characterized by sterile pustule formation in palms and soles and a recurrent disease course. Although we have many treatments for PPP, there is no authoritative guidance.

AREAS COVERED

A thorough search of PubMed was conducted to identify studies in PPP from 1973 onwards, with additional references to specific articles. Any treatment methods were outcomes of interest, including topical treatment, systemic treatment, biologics, other targeted treatments, phototherapy, and tonsillectomy.

EXPERT OPINION

Topical corticosteroids are suggested as first-line therapy. Oral acitretin has become the most applied systemic retinoid recommended in PPP without joint involvement. For patients with arthritis, immunosuppressants like cyclosporin A and methotrexate are more recommended. UVA1, NB-UVB, and 308-nm excimer laser are effective phototherapy options. The combinations of topical or systemic agents and phototherapy may enhance the efficacy, particularly in recalcitrant cases. Secukinumab, ustekinumab, and apremilast are the most investigated targeted therapies. However, heterogeneous reported outcomes in clinical trials provided low-to-moderate quality evidence of their efficacy. Future studies are required to address these evidence gaps. We suggest managing PPP based on the acute phase, maintenance phase, and comorbidities.

Evaluation of the area subscore of the Palmoplantar Pustulosis Area and Severity Index using an attention U-net deep learning algorithm

Palmoplantar pustulosis (PPP) is a variant of pustular psoriasis involving the palms and soles. The severity of PPP is usually evaluated using the Palmoplantar Pustulosis Area and Severity Index (PPPASI). Among the components of the PPPASI, the area of the involved lesion is evaluated differently by raters, who generally make a rough estimate using the eye and not through a specific calculation. To overcome inconsistent evaluation of the area subscore of PPPASI by human raters, we developed and validated deep-learning-based algorithms to enable automated and reliable assessment of the area involved in PPP to provide clinical advantages. In this study, we developed a dataset of 611 images of the palms and soles of 153 patients with PPP. We evaluated the area of the lesion by dividing the number of pixels in the area involved in PPP by the number of pixels in the area of the palms or soles. Using attention U-net, we developed two convolutional neural network (CNN) models that can evaluate the percentage of the affected area (%) and subsequently assign a score ranging from 0 to 6. The area subscore of PPPASI evaluated by the deep-learning algorithm was same or differed by 1-point from the subscore of ground truth in 98.8% of the images. The intraclass correlation coefficient between the CNN and ground truth was 0.879, indicating good agreement. The accuracy and mean absolute error of the model were 66.7% and 0.344, respectively. In a Bland-Altman plot, most of the differences in the percentage of the affected area lay between the 95% confidence interval with a mean difference of 0 and a standard deviation of 0.2. The deep-learning algorithm can provide several clinical advantages by objectively evaluating the components of the PPPASI without concern for disagreement between clinicians. The algorithms further enable cumulative clinical data acquisition related to PPP severity.

Economic Burden of Palmoplantar Pustulosis in Sweden: A Population-based Register Study

The aim of this study was to estimate the economic burden of palmoplantar pustulosis, a chronic relapsing skin condition commonly occurring in combination with psoriasis vulgaris. Using data from the Swedish National Patient Register and Swedish Prescribed Drug Register for 2015, the study estimated all-cause and palmoplantar pustulosis-specific healthcare resource use (inpatient stays, physician visits and drug use) for 14,715 patients with palmoplantar pustulosis, and compared these both with matched controls from the general population and with patients with psoriasis vulgaris (without palmoplantar pustulosis). Mean annual direct costs for a patient with palmoplantar pustulosis was higher compared with costs for the general population (3,000 vs 1,700 Euro, p < 0.001). Compared with psoriasis vulgaris, more patients with palmoplantar pustulosis had inpatient stays, but fewer had physician visits and psoriasis-related drugs; the overall costs were similar. Only a small fraction of the costs of physician visits and inpatient stays for patients with palmoplantar pustulosis were attributable to specific palmoplantar pustulosis problems, indicating a clear comorbidity burden in palmoplantar pustulosis.

[Palmoplantar Pustulosis]

N/a.

Comparison of the Inflammatory Circuits in Psoriasis Vulgaris, Non‒Pustular Palmoplantar Psoriasis, and Palmoplantar Pustular Psoriasis

Palmoplantar pustular psoriasis (PPPP) and non‒pustular palmoplantar psoriasis (NPPP) are localized, debilitating forms of psoriasis. The inflammatory circuits involved in PPPP and NPPP are not well-understood. To compare the cellular and immunological features that differentiate PPPP and NPPP, skin biopsies were collected from a total of 30 participants with PPPP, NPPP, and psoriasis vulgaris (PV) and from 10 healthy participants. A subset consented to a second biopsy after 3 additional weeks off medication. Histologic staining of lesional and nonlesional skin showed higher neutrophil counts in PPPP than in NPPP and PV and higher CD8⁺ T-cell counts in NPPP. RNA sequencing and transcriptional analysis of skin biopsies showed enhanced IFN-γ pathway activation in NPPP lesions but stronger signatures of IL-17 pathway and neutrophil-related genes (e.g., IL36A) in PPPP lesional skin. Serum analysis on the Olink platform detected higher concentrations of T helper type 1, IFN-γ‒inducible chemokines in NPPP, and higher neutrophil-associated cytokines in PPPP. Taken together, this evidence suggests more pronounced T helper 1‒mediated inflammation in NPPP than in PV and PPPP and stronger neutrophil-associated activity in PPPP than in NPPP and PV. These data support targeting inflammatory pathways associated with neutrophilic inflammation (e.g., IL-36 signaling) for therapeutic development in PPPP.

CNVs Associated with Different Clinical Phenotypes of Psoriasis and Anti-TNF-Induced Palmoplantar Pustulosis

Background: Psoriasis can present different phenotypes and could affect diverse body areas. In contrast to the high effectiveness of biological drugs in the treatment of trunk and extremities plaque psoriasis, in palmoplantar phenotypes and in plaque scalp psoriasis, these same drugs usually have reduced efficacy. Anti-TNF drugs could induce the appearance of palmoplantar pustulosis (PPP) in patients with other inflammatory diseases. The objective of this study is to identify if there are DNA Copy Number Variations (CNVs) associated with these different clinical phenotypes, which could justify the differences found in clinical practice. Moreover, we intend to elucidate if anti-TNF-induced PPP has a similar genetic background to idiopathic PPP. Methods: Skin samples were collected from 39 patients with different patterns of psoriasis and six patients with anti-TNF-induced PPP. The CNVs were obtained from methylation array data (Illumina Infinium Human Methylation) using the conumee R package. Results: No significant CNVs were found between the different phenotypes and the locations of psoriasis compared. Nevertheless, we found two significant bins harboring five different genes associated with anti-TNF-induced PPP in patients with a different background other than psoriasis. Conclusions: Our results may help to predict which patients could develop anti-TNF-induced PPP.

Narrative Review of the Emerging Therapeutic Role of Brodalumab in Difficult-to-Treat Psoriasis

Psoriatic involvement in areas of the body such as nails, palms and soles (palmoplantar), and scalp is associated with dramatically negative effects on quality of life relative to involvement elsewhere in the body. Although numerous evidence-based studies demonstrate the efficacy of biologics for overall skin clearance in moderate-to-severe plaque psoriasis (including tumor necrosis factor α [TNFα] inhibitors and interleukin [IL]-17A, IL-12/IL-23, IL-23, IL-17F, and IL-17A/F inhibitors), large, randomized, placebo-controlled clinical studies of psoriasis with nail, palmoplantar, and scalp involvement are needed to better inform decision-making in clinical practice. Moreover, biologic failure caused by drug ineffectiveness is a common occurrence in patients who do not respond, lose response, or are intolerant to treatment. Brodalumab is a fully human IL-17 receptor A antagonist that demonstrates high rates of skin clearance among the latest generation of biologic therapies for treatment of moderate-to-severe psoriasis. This review summarizes current literature on the efficacy of brodalumab and other therapies in difficult-to-treat psoriasis including psoriasis in difficult-to-treat locations (such as psoriasis with nail, palmoplantar, or scalp involvement) and psoriasis in patients whose disease did not respond to other biologics.

Risks of Comorbidities in Patients With Palmoplantar Pustulosis vs Patients With Psoriasis Vulgaris or Pompholyx in Korea

Importance

Palmoplantar pustulosis (PPP) has been reported to be accompanied by systemic conditions. However, the risks of comorbidities in patients with PPP have rarely been evaluated.

Objective

To assess the risks of comorbidities in patients with PPP compared with patients with psoriasis vulgaris or pompholyx.

Design, Setting, and Participants

This nationwide population-based cross-sectional study used data from the Korean National Health Insurance database and the National Health Screening Program collected from January 1, 2010, to December 31, 2019. Data were analyzed from July 1, 2020, to October 31, 2021. Korean patients diagnosed with PPP, psoriasis vulgaris, or pompholyx who visited a dermatologist between January 1, 2010, and December 31, 2019, were enrolled.

Exposures

Presence of PPP.

Main Outcomes and Measures

The risks of comorbidities among patients with PPP vs patients with psoriasis vulgaris or pompholyx were evaluated using a multivariable logistic regression model.

Results

A total of 37 399 patients with PPP (mean [SD] age, 48.98 [17.20] years; 51.7% female), 332 279 patients with psoriasis vulgaris (mean [SD] age, 47.29 [18.34] years; 58.7% male), and 365 415 patients with pompholyx (mean [SD] age, 40.92 [17.63] years; 57.4% female) were included in the analyses. Compared with patients with pompholyx, those with PPP had significantly higher risks of developing psoriasis vulgaris (adjusted odds ratio [aOR], 72.96; 95% CI, 68.19-78.05; P < .001), psoriatic arthritis (aOR, 8.06; 95% CI, 6.55-9.92; P < .001), ankylosing spondylitis (aOR, 1.91; 95% CI, 1.61-2.27; P < .001), type 1 diabetes (aOR, 1.33; 95% CI, 1.16-1.52; P < .001), type 2 diabetes (aOR, 1.33; 95% CI, 1.29-1.38; P < .001), Graves disease (aOR, 1.25; 95% CI, 1.11-1.42; P < .001), Crohn disease (aOR, 1.63; 95% CI, 1.11-2.40; P = .01), and vitiligo (aOR, 1.87; 95% CI, 1.65-2.12; P < .001) after adjusting for demographic covariates. The risks of ankylosing spondylitis (aOR, 1.37; 95% CI, 1.16-1.62; P < .001) and Graves disease (aOR, 1.40; 95% CI, 1.23-1.58; P < .001) were significantly higher among patients with PPP vs psoriasis vulgaris. However, the risks of psoriatic arthritis (aOR, 0.54; 95% CI, 0.47-0.63; P < .001), systemic lupus erythematosus (aOR, 0.67; 95% CI, 0.46-0.97; P = .04), Sjögren syndrome (aOR, 0.70; 95% CI, 0.50-0.96; P = .03), systemic sclerosis (aOR, 0.29; 95% CI, 0.11-0.77; P = .01), vitiligo (aOR, 0.53; 95% CI, 0.47-0.60; P < .001), and alopecia areata (aOR, 0.88; 95% CI, 0.81-0.95; P = .001) were significantly lower among those with PPP vs psoriasis vulgaris.

Conclusions and Relevance

The results of this cross-sectional study suggest that patients with PPP have an overlapping comorbidity profile with patients with psoriasis vulgaris but not patients with pompholyx. However, the risks of comorbidities among patients with PPP may be substantially different from those among patients with psoriasis vulgaris.

Psoriasis in Saudi Population: Gender Differences in Clinical Characteristics and Quality of Life

Introduction

Patients with psoriasis suffer from an inflammatory immune-mediated skin condition that impacts their quality of life severely. In our study, we aimed to analyze the gender differences in clinical characteristics in patients with psoriasis and to assess the quality of life in these patients.

Methods

This is a retrospective observational study that was conducted at King Abdulaziz Medical City (KAMC) in Jeddah, Saudi Arabia.

Results

A total of 139 patients with psoriasis met the inclusion criteria, with a mean ± SD age of 45.53 ± 15.3 years. No statistically significant gender differences were observed in terms of disease duration, BMI, clinical type and body surface area (BSA) (P=0.657, P=0.782, P=0.565, P=0.088, respectively). However, psoriasis caused a significant impairment in the quality of life in female patients compared to males (P=0.036).

Conclusion

This study reports the gender differences in clinical characteristics in patients with psoriasis and its impact on the quality of life. More researches with larger sample size and different populations are needed in order to identify more potential gender-specific variations.

Evaluation of a Case Series of Patients With Palmoplantar Pustulosis in the United States

Importance

Palmoplantar pustulosis (PPP) is a is a chronic, orphan disease with limited epidemiological data.

Objective

To describe the clinical characteristics, treatments, longitudinal disease course, and health care utilization in adults with PPP across the US.

Design, Setting, and Participants

This retrospective, longitudinal case series from 20 academic dermatology practices in the US included a consecutive sample of 197 adults who met the European Rare and Severe Psoriasis Expert Network consensus definition for PPP between January 1, 2007, and December 31, 2018. Data analysis was performed June 2020 to December 2020.

Main Outcomes and Measures

The primary outcome was to describe the patient characteristics, associated medical comorbidities, treatment patterns, complications, and PPP-specific health care utilization.

Results

Of 197 patients, 145 (73.6%) were female, and the mean (SD) age at presentation was 53.0 (12.6) years, with a mean (SD) follow-up time of 22.1 (28.0) months. On initial presentation, 95 (48.2%) patients reported skin pain, and 39 (19.8%) reported difficulty using hands and/or feet. Seventy patients (35.5%) were treated with systemic treatments, and use of more than 20 different systemic therapies was reported. In patients with at least 6 months of follow-up (n = 128), a median (IQR) of 3.7 (4-10) dermatology visits per year were reported; 24 (18.8%) patients had 5 or more visits during the study period.

Conclusions and Relevance

In this case series, PPP was associated with persistent symptoms, continued health care utilization, and a lack of consensus regarding effective treatments, emphasizing the unmet medical need in this population. Additional research is necessary to understand treatment response in these patients.

Pustular Psoriasis: From Pathophysiology to Treatment

Pustular psoriasis (PP) is a clinicopathological entity encompassing different variants, i.e., acute generalized PP (GPP), PP of pregnancy (impetigo herpetiformis), annular (and circinate) PP, infantile/juvenile PP, palmoplantar PP/palmoplantar pustulosis, and acrodermatitis continua of Hallopeau (ACH), which have in common an eruption of superficial sterile pustules on an erythematous base. Unlike psoriasis vulgaris, in which a key role is played by the adaptive immune system and interleukin (IL)-17/IL-23 axis, PP seems to be characterized by an intense inflammatory response resulting from innate immunity hyperactivation, with prominent involvement of the IL-36 axis. Some nosological aspects of PP are still controversial and debated. Moreover, owing to the rarity and heterogeneity of PP forms, data on prognosis and therapeutic management are limited. Recent progresses in the identification of genetic mutations and immunological mechanisms have promoted a better understanding of PP pathogenesis and might have important consequences on diagnostic refinement and treatment. In this narrative review, current findings in the pathogenesis, classification, clinical features, and therapeutic management of PP are briefly discussed.

Recent advances in palmoplantar pustulosis

Palmoplantar pustulosis (PPP) is a chronic inflammatory condition where crops of sterile pustules with erythematous keratotic lesions causing bleeding and pain appear on the palms and soles. Recently, the European Rare and Severe Expert Network considered PPP as a variant of pustular psoriasis with or without psoriasis vulgaris.

The prevalence of PPP varies from 0.050 to 0.12%. PPP occurs more frequently in women and the highest prevalence occurred between the ages of 50 and 69 years. Nail psoriasis seems to be frequent in PPP, ranging from 30 to 76%, and psoriatic arthritis in 8.6 to 26% of PPP patients.

Synovitis, acne, pustulosis, hyperostosis, osteitis (SAPHO) syndrome and pustulotic arthro-osteitis are considered PPP-associated disorders. PPP has been reported with other co-morbidities such as psychiatric disorders, thyroid-associated disease, altered calcium homeostasis, gluten sensitivity diabetes, obesity, and dyslipidemia, but larger studies are required to prove such associations. Environmental exacerbating factors might contribute to the onset or worsening of PPP such as cigarette smoking, stress, focal infections, metal allergies, and drug intake. Genetic predisposition plays an important role in PPP.

In PPP, both the innate and the adaptive immune systems are activated. The acrosyringeal expression of IL-17 has been demonstrated, indicating that the eccrine sweat gland is an active component of the skin barrier and an immune-competent structure. Increased levels of several inflammatory molecules, including IL-8, IL-1α, IL-1β, IL-17A, IL-17C, IL-17D, IL-17F, IL-22, IL-23A, and IL-23 receptor, have been detected in PPP biopsies. Increased serum levels of TNF-α, IL-17, IL-22, and IFN-γ have been detected in patients with PPP in comparison to healthy subjects, suggesting a similar inflammatory pattern to psoriasis vulgaris. Oral and tonsillar infections serve as trigger factors for PPP.

Long-term therapy is required for many patients, but high-quality data are limited, contributing to uncertainty about the ideal approach to treatment.

Pharmacokinetic/Pharmacodynamic Analysis of Guselkumab for Treatment of Palmoplantar Pustulosis: Clinical Implications of Guselkumab Dose, Disease Severity and Smoking in Japanese Patients

Guselkumab is a human IgG1λ monoclonal antibody that has been approved for treatment of multiple immunological diseases including palmoplantar pustulosis (PPP) in Japan. The efficacy of guselkumab in reducing disease severity as compared with placebo has been demonstrated in phase 2 and 3 clinical studies. In some patients assigned to the placebo treatment, worsening of PPP Area and Severity Index (PPPASI) score was noted. Most of these patients were smokers, raising a possibility of an association of smoking with the disease progression. To understand the clinical implications of guselkumab dose, baseline disease severity and smoking on the treatment effect and describe the longitudinal relationship between guselkumab exposure and the PPPASI score, a PK/PD modeling analysis was conducted using the pooled data from one phase 2 and one phase 3 study. Data from 207 Japanese patients (77% women and 60% smokers) with a median PPPASI score of 24.6 were included in the analysis. The observed treatment efficacy (the PPPASI score reduction) appeared to be similar at the current approved dose (100) mg and the higher dose (200 mg). Greater extent of the PPPASI score reduction (in absolute points) is expected in patients with higher baseline PPPASI score (severe disease). However, the higher baseline did not translate to larger magnitude of the change from baseline (in percentage) in the PPPASI score. Incorporating a linear disease progression effect in the model significantly decreased the NONMEM objective function value (p<0.001). Smoking status appeared tobe related to disease worsening in some patients, but the covariate did not reach statistical significance in the model. This article is protected by copyright. All rights reserved.

Clinical characteristics and treatment status of pustulotic arthro-osteitis: A single-center study involving 51 cases

Pustulotic arthro-osteitis (PAO) is a major complication of palmoplantar pustulosis (PPP). In orthopedic surgery outpatient clinics, PPP patients with osteoarticular symptoms are seen frequently, but PAO's clinical features remain not well known. To determine Japanese patients' clinical features and treatment status with PAO, we conducted a single-center retrospective epidemiologic survey. Clinical features, including gender, age, smoking habit, the onset pattern, interval between skin manifestation and osteoarticular symptoms, and the incidence of sternoclavicular joint lesions, axial and peripheral joint lesions, were examined. The association between physical status and image findings by X-ray, computed tomography, bone scintigraphy with Technetium⁹⁹ , or magnetic resonance imaging was evaluated. The distribution pattern of peripheral joint lesions and the treatment status were evaluated. We identified 51 patients, 10 men and 41 women, with PAO. The average age was 48 years and 59% were smokers. The frequency of onset patterns was skin-leading type (63%), simultaneous onset (18%), and osteoarticular leading type (16%). The average interval between skin involvement and osteoarticular involvement in skin-leading type was significantly longer than that in osteoarticular leading type (7.1 years vs. 2.0 years). A sternoclavicular joint (SCJ) lesion was detected in 65% cases, and the physical findings of SCJ were significantly related to the image findings. Axial and peripheral joint lesions were detected in the same ratio (23 cases, 45%). In the peripheral joints, the finger joint was the most common (26%), followed by the shoulder joint (21%). Patients were treated with nonsteroidal anti-inflammatory drugs (76%), followed by conventional synthetic disease-modifying antirheumatic drugs (DMARDs) (29%) and biological DMARDs (9.8%). Tonsillectomy was performed in 11 cases. In conclusion, PAO more frequently involves SCJ in middle-aged women who smoke. Given that osteoarticular leading type was detected in 16% cases, seronegative oligoarthritis patients should be monitored for PPP, leading to a diagnosis of PAO.

Clinical characteristics, quality of life and risk factors for severity in palmoplantar pustulosis: a cross-sectional, multicentre study of 263 patients

BACKGROUND

Palmoplantar pustulosis (PPP) is a rare, chronic, inflammatory skin disease characterized by sterile pustules on palmar or plantar areas. Data on PPP are scarce.

AIM

To investigate the clinical characteristics and risk factors for disease severity in a large cohort of Turkish patients with PPP.

METHODS

We conducted a cross-sectional, multicentre study of patients with PPP recruited from 21 tertiary centres across Turkey.

RESULTS

In total, 263 patients (165 women, 98 men) were evaluated. Most patients (75.6%) were former or current smokers. The mean Palmoplantar Pustulosis Area and Severity Index (PPPASI) was 8.70 ± 8.06 and the mean Dermatology Life Quality Index (DLQI) score was 6.87 ± 6.08, and these scores were significantly correlated (r = 0.52, P < 0.001). Regression analysis showed that current smoking was significantly associated with increased PPPASI (P = 0.03). Coexisting psoriasis vulgaris (PsV) was reported by 70 (26.6%) patients. Male sex prevalence, PPP onset incidence, disease duration, DLQI, and prevalence of nail involvement and psoriatic arthritis (PsA) were significantly increased among patients with PPP with PsV. Of the 263 patients, 18 (6.8%) had paradoxical PPP induced by biologic therapy, and these patients had significantly increased mean DLQI and prevalence of PsA (r = 0.03, P = 0.001).

CONCLUSION

Our data suggest that smoking is a risk factor for both PPP development and disease severity. Patients with PPP with PsV present distinct clinical features and patients with biologic therapy-induced paradoxical PPP have reduced quality of life and are more likely to have PsA.

Interventions for chronic palmoplantar pustulosis: abridged Cochrane systematic review and GRADE assessments

BACKGROUND

Palmoplantar pustulosis (PPP) is a chronic inflammatory disease in which sterile and relapsing pustules appear on the palms and soles.

OBJECTIVES

To assess the effects of interventions for chronic PPP to induce and maintain complete remission.

METHODS

We searched for randomized controlled trials (RCTs), including people with PPP or chronic palmoplantar pustular psoriasis, in the Cochrane Skin Specialised Register, CENTRAL, MEDLINE, Embase, LILACS and eight trials registers up to July 2020. Study selection, data extraction and risk-of-bias assessment were carried out independently by two review authors. Certainty of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) method.

RESULTS

We included 37 RCTs (1663 participants, 76% women, mean age 50 years). Mean treatment duration was 11 weeks. Topical vitamin D derivative may be more effective than placebo in achieving clearance [risk ratio (RR) 7·83, 95% confidence interval (CI) 1·85-33·12; low-certainty evidence from two trials]. Concerning biological therapies, there was little or no difference between etanercept and placebo in achieving clearance (low-certainty evidence from one trial), ustekinumab is less effective than placebo in reducing severity (low-certainty evidence from one trial), and guselkumab (RR 2·88, 95% CI 1·24-6·69) and secukinumab (RR 1·55, 95% CI 1·02-2·35) are probably better in reducing disease severity (moderate-certainty evidence from two and one trial(s), respectively) but may cause more serious adverse events than placebo.

CONCLUSIONS

Evidence is lacking for or against major chronic PPP treatments. Risk of bias and imprecision limit our confidence in the results.

Comparison of the Efficacy and Safety of Apremilast and Methotrexate in Patients with Palmoplantar Psoriasis: A Randomized Controlled Trial

BACKGROUND

Placebo-controlled studies have reported the efficacy of apremilast in the management of palmoplantar psoriasis but studies comparing efficacy with a conventional agent are lacking.

OBJECTIVE

The objective of this article was to  compare the efficacy and safety of apremilast and methotrexate in patients with palmoplantar psoriasis.

METHODS

In this prospective, randomized, active-controlled, observer-blinded clinical trial, conducted at a psoriasis clinic of a tertiary care institute in India from 1 July, 2019 to 1 June, 2020, 84 patients with palmoplantar psoriasis were randomized (1:1) to receive either methotrexate (0.4 mg/kg/week orally) or apremilast (30 mg twice daily). The treatment protocol was continued for 16 weeks or until achieving a ≥ 75% improvement in the Modified Palmoplantar Psoriasis Area and Severity Index (m-PPPASI 75), whichever was earlier. Changes in m-PPPASI and Dermatology Life Quality Index scores from baseline, the proportion of patients achieving m-PPPASI 75, and adverse events were assessed.

RESULTS

Eighty-four patients were included (76 palmoplantar psoriasis and 8 palmoplantar pustulosis). The mean age (standard deviation) was 44.5 (12.9) years and 53 (63%) were women. The m-PPPASI score [median (interquartile range)] after 16 weeks of treatment showed a significant improvement from baseline in both apremilast [- 6.3 (10.9), p < 0.001] and methotrexate groups [- 8.5 (9.9), p < 0.001]. The estimated median difference between the groups was - 1.2 (p = 0.39, 95% confidence interval - 4.2 to 2.1). At 16 weeks, m-PPPASI 75 was achieved by 14/42 (33%) and 17/42 (41%) patients in the apremilast and methotrexate groups, respectively (p = 0.49). A significant reduction in the Dermatology Life Quality Index score [median (interquartile range)] was observed in both groups [apremilast: - 3.0 (6.0), p < 0.001; methotrexate: - 3.0 (6.3), p < 0.001] with an estimated median difference of 0.0 (p = 0.99, 95% confidence interval - 1.0 to 2.0). The proportion of patients experiencing adverse events was comparable (p = 0.49).

CONCLUSIONS

Apremilast showed a comparable efficacy and safety profile to methotrexate in the management of palmoplantar psoriasis.

CLINICAL TRIAL REGISTRATION

CTRI/2019/06/019830, date of registration: 24 June, 2019; trial registered prospectively.

MrgprC11+ sensory neurons mediate glabrous skin itch

Itch arising from glabrous skin (palms and soles) has attracted limited attention within the field due to the lack of methodology. This is despite glabrous itch arising from many medical conditions such as plantar and palmar psoriasis, dyshidrosis, and cholestasis. Therefore, we developed a mouse glabrous skin behavioral assay to investigate the contribution of three previously identified pruriceptive neurons in glabrous skin itch. Our results show that MrgprA3⁺ and MrgprD⁺ neurons, although key mediators for hairy skin itch, do not play important roles in glabrous skin itch, demonstrating a mechanistic difference in itch sensation between hairy and glabrous skin. We found that MrgprC11⁺ neurons are the major mediators for glabrous skin itch. Activation of MrgprC11⁺ neurons induced glabrous skin itch, while ablation of MrgprC11⁺ neurons reduced both acute and chronic glabrous skin itch. Our study provides insights into the mechanisms of itch and opens up new avenues for future glabrous skin itch research.

Prevalence and incidence of palmoplantar pustulosis in Sweden: a population-based register study

BACKGROUND

Palmoplantar pustulosis (PPP) is a chronic relapsing skin condition characterized by sterile pustules on the palm and soles. Population-based estimates of PPP incidence and prevalence are limited.

OBJECTIVES

To estimate the prevalence and incidence of PPP in the Swedish general population and to estimate the prevalence of psoriasis vulgaris among the population with PPP.

METHODS

The Swedish National Patient Register was used, covering all inpatient and outpatient nonprimary care for the Swedish population. We identified cases (2004-2015) with one International Classification of Diseases 10^th Revision diagnostic code (base case) for PPP. The point prevalence estimates at the end of this period (31 December 2015) were obtained by linkage to the Swedish Total Population Register. In sensitivity analyses, we used alternative case definitions: (i) requiring two visits and (ii) requiring two visits, one of which was within dermatology or internal medicine.

RESULTS

The base case prevalence of PPP was estimated to be 147 per 100 000 (women 227, men 68) and the annual prevalence was estimated to 26 per 100 000 in 2015. Among the population of people with PPP, 17% were registered with a diagnostic code for psoriasis vulgaris. The incidence of PPP in 2015 was estimated to be 12·7 per 100 000 (women 18·7, men 6·6). The criteria used had an impact on the prevalence and incidence estimates: strict case 1 gave an overall prevalence of 72 per 100 000 and an incidence of 5·4 per 100 000.

CONCLUSIONS

The results indicate that the population-based prevalence of PPP may be larger than previously estimated. However, the estimates were sensitive to the employed PPP case criteria. The findings enhance demands for studies using validated diagnostic algorithms potentially also including data from primary care.

Successful Treatment of Refractory Palmoplantar Pustular Psoriasis With Apremilast: A Case Series

Introduction: Palmoplantar pustular psoriasis (PPPP) is a debilitating inflammatory skin disorder of the palms and soles that poses a high burden on affected patients. Satisfactory treatment response is rarely achieved using current treatment options, little is known about the potential benefit of the PDE4 inhibitor apremilast in the treatment of refractory PPPP patients. We aimed to evaluate the use of apremilast in PPPP patients. Patients and Methods: Six patients, four with severe physician global assessment (PGA) = 3 on a scale of 0-4 and two with very severe (PGA = 4) treatment-refractory PPPP [mean age (years ± SD): 56.2 ± 15.6], were included in this study. Five patients had concomitant psoriatic arthritis (PsA). Prior to apremilast administration, topical corticosteroids, psoralen-UVA and multiple systemic oral and biologic anti-inflammatory treatments were insufficient to improve their skin condition or had to be discontinued due to adverse events. Apremilast (titrated to a maintenance dose of 30 mg 2x/d) was commenced in all patients with clinical follow-up over 18 months. Results: Within the first 4 weeks of treatment, each patient's symptoms improved as assessed by PGA score. At 3 months, four patients had a mild PGA score and two were cleared from PPPP. After 18 months of follow-up, three patients improved from PGA = 3 to PGA = 1 and one patient from PGA = 4 to PGA = 1. Two patients discontinued treatment, one due to a lack of efficacy against PsA and the other to a desire to have a child. However, both patients recorded improvements before discontinuing treatment. Conclusion: Apremilast may be a promising treatment option for refractory and severely affected PPPP patients. Our observation, however, requires further validation.

Palmoplantar Pustulosis: A Case Report

Introduction

Dermatology complaints account for 3.3% of emergency department (ED) visits per year. Most rashes are benign, but there are a select few that emergency physicians must be familiar with as delay in treatment could be life threatening.

Case Report

A well-appearing, 76-year-old male presented to the ED with multiple coalescing pustules to his palms and soles and was transferred to the nearest tertiary care hospital for dermatology consult. He was diagnosed with palmoplantar pustulosis and discharged home with a five-day course of clobetasol propionate 0.05% cream twice daily and outpatient dermatology follow-up.

Conclusion

Palmoplantar pustulosis is an uncommon skin condition characterized by recurrent eruptions of sterile pustules localized to the palms and soles. Emergency physician awareness of this rare diagnosis may help prevent hospital admissions and lead to earlier initiation of treatment with outpatient dermatology follow-up.

Comorbidities in patients with palmoplantar plaque psoriasis

BACKGROUND

Psoriasis has been shown to be associated with several comorbidities. Whether the palmoplantar subtype of plaque psoriasis carries similar risks for comorbidities as generalized plaque psoriasis remains to be defined.

OBJECTIVE

To examine the association between palmoplantar plaque psoriasis and comorbidities known to be associated with generalized plaque psoriasis.

METHODS

We retrospectively compared the prevalence of comorbidities previously found to be associated with generalized plaque psoriasis among 163 patients with palmoplantar plaque psoriasis who had been treated with topical psoralen and ultraviolet A from 2009 to 2017 and a cohort of 781 control individuals. Each patient with psoriasis was matched according to sex and age (±1 year) with up to 5 control individuals. Conditional logistic regression was used to evaluate the associations after matching.

RESULTS

Diabetes mellitus (odds ratio [OR], 2.296), cardiovascular disease (OR, 1.797), and most remarkably, mood disorders (OR, 6.232) were significantly associated with palmoplantar plaque psoriasis. Dyslipidemia, hypertension, and psoriatic arthritis were more frequent among patients with palmoplantar plaque psoriasis, but those associations did not reach statistical significance.

LIMITATIONS

The retrospective nature of this study, the fact that some data were collected through a survey questionnaire, and the relatively small sample size suggest the need to validate the present data in a prospective manner. Additionally, within the psoriasis group, patients were assessed for the presence of comorbidities during the whole follow-up period, whereas the comorbidities of individuals in the control group were assessed during a baseline visit.

CONCLUSIONS

Several comorbidities known to be associated with psoriasis vulgaris were also found to be prevalent in a series of patients with plaque palmoplantar psoriasis. Individuals affected with plaque palmoplantar psoriasis showed a particularly high risk for mood disorders.

Diagnosis, Screening and Treatment of Patients with Palmoplantar Pustulosis (PPP): A Review of Current Practices and Recommendations

Palmoplantar pustulosis (PPP) is a rare, chronic, recurrent inflammatory disease that affects the palms and/or the soles with sterile, erupting pustules, which are debilitating and usually resistant to treatment. It has genetic, histopathologic and clinical features that are not present in psoriasis; thus, it can be classified as a variant of psoriasis or as a separate entity. Smoking and upper respiratory infections have been suggested as main triggers of PPP. PPP is a challenging disease to manage, and the treatment approach involves both topical and systemic therapies, as well as phototherapy and targeted molecules. No gold standard therapy has yet been identified, and none of the treatments are curative. In patients with mild disease, control may be achieved with on-demand occlusion of topical agents. In patients with moderate-to-severe PPP, phototherapy or a classical systemic agent (acitretin being the best treatment option, especially in combination with PUVA) may be effective. Refractory patients or those with contraindications to use these therapies may be good candidates for apremilast or biologic therapy, particularly anti-IL-17A and anti-IL-23 agents. Recent PPP trials are focusing on blockage of IL-36 or IL-1 pathways, which play an important role in innate immunity. Indeed, IL-36 isoforms have been strongly implicated in the pathogenesis of psoriasis. Therefore, blockage of the IL-36 pathway has become a new treatment target in PPP, and three studies are currently evaluating the use of monoclonal antibodies that block the IL-36 receptor in PPP: ANB019 and spesolimab (BI 655130). In this review, we explore the diagnosis, screening and treatment of patients with PPP.

Palmoplantar Pustulosis: Recent Advances in Etiopathogenesis and Emerging Treatments

Palmoplantar pustulosis (PPP) is a chronic, recurrent skin disease belonging to the spectrum of psoriasis. It is characterized by an eruption of sterile pustules on the palms and soles. Recent studies in PPP have focused on genetic differences between pustular phenotypes and the role of the innate immunological system and the microbiome in the etiopathogenesis of the disease. Mutations in IL36RN (a major predisposing factor for generalized pustular psoriasis) were found in selected patients with PPP and were associated with earlier disease onset. Studies have shown that the interleukin (IL)-17 and IL-36 pathways might be involved in the pathogenesis of PPP. A microbiome has been demonstrated in the vesicopustules of PPP, and an abundance of Staphylococcus appears to be increased by smoking. Improved understanding of the underlying etiopathogenesis of PPP has led to advances in treatment options, and targeted therapies for PPP have been evaluated or are under evaluation against more than 12 molecules in ongoing clinical trials. These targets include CXCR2 (IL-8 receptor type B), granulocyte colony-stimulating factor receptor, IL-1 receptor, IL-8, IL-12, IL-23, IL-17A, IL-17 receptor, IL-36 receptor, phosphodiesterase-4, and tumor necrosis factor-α.

Treatment patterns and healthcare resource utilization in palmoplantar pustulosis patients in Japan: A claims database study

Background

Palmoplantar pustulosis (PPP) is a chronic, relapsing, inflammatory autoimmune condition, characterized by sterile pustules on the palms and soles. The treatment patterns of PPP and total health care resource utilization in Japan are not well described. Investigating these areas is needed to understand current PPP management in Japan.

Objective

To describe the characteristics, medication treatment and health care resource utilization patterns, and associated costs of PPP patients in Japan.

Methods

A retrospective analysis of insurance claims data was conducted using the Japan Medical Data Center database. Adult Patients with at least two claims with a PPP diagnosis from January 1, 2011 to March 30, 2017 and six months of follow-up after the first diagnosis were included. Patient characteristics described include age, gender, and comorbid conditions. Treatment patterns assessed include the types of treatment, sequence of treatment, and rates of discontinuation, switching, persistence and use of concomitant medications.

Results

A total of 5,162 adult patients met all inclusion criteria. Mean (SD) patient age was 49.7 (11.6) years and 43.2% were male. A total of 2441 patients (47.8%) received systemic non-biologic drugs during the entire follow up period, 2,366 (46.4%) were prescribed topical therapy, 273 (5.4%) were prescribed phototherapy, while 18 (0.4%) of patients with other autoimmune comorbidities were eligible for prescribed biologics. For treatment-naïve patients with mild PPP, topical therapy was most commonly (77.1%) prescribed, whereas in moderate to severe cases of PPP, systemic non-biologic drugs (65%) were most often used. The frequency of switching was similar (64.3% to 75.3%) across various therapies and treatment lines.

Conclusion

This study describes the treatment patterns and health care resource utilization for Japanese PPP patients using a large claims database, and highlights an unmet need to derive better treatment strategies for PPP and address disease burden in Japan.

Sex- and gender-associated clinical and psychosocial characteristics of patients with psoriasis

BACKGROUND

Sex and gender may affect disease prevalence, adverse effects and response to therapy.

AIM

To analyse sex and gender differences in outpatients with psoriasis.

METHODS

A cross-sectional study was conducted at IDI-IRCCS, Rome, over a 3-year period. In total, 3023 patients with psoriasis were enrolled. Anthropometric and demographic characteristics were recorded, and a dermatologist evaluated the clinical severity of disease. Quality of life (QoL) questionnaires were collected. Univariate and multivariate analyses were performed to examine factors associated with sex.

RESULTS

We found sex- and gender-associated differences in clinical characteristics, disease severity, psychological distress and quality of life. Male sex was associated with body mass index, smoking, alcohol consumption, Psoriasis Area Severity Index ≥ 10 and age at onset ≥ 20 years. Female sex was associated with family history of diabetes, joint involvement, clinical type other than diffuse plaque psoriasis, higher psychological distress and a greater effect on QoL.

CONCLUSION

Our study identified sex and gender differences of potential clinical relevance in psoriasis.

Efficacy of guselkumab in a subpopulation with pustulotic arthro-osteitis through week 52: an exploratory analysis of a phase 3, randomized, double-blind, placebo-controlled study in Japanese patients with palmoplantar pustulosis

Background

Previous studies of guselkumab have demonstrated clinical benefits in patients with plaque‐type psoriasis, generalized pustular psoriasis, erythrodermic psoriasis and palmoplantar pustulosis (PPP).

Objective

The aim of this exploratory analysis of a double‐blind, multicenter, placebo‐controlled, phase 3 study in Japanese patients with PPP was to evaluate the efficacy of guselkumab in the subset of patients with pustulotic arthro‐osteitis (PAO).

Methods

Patients were randomized to receive guselkumab 100 or 200 mg at weeks 0, 4, 12 and every 8 weeks, or placebo with cross‐over to guselkumab 100 or 200 mg at week 16 (placebo group). Efficacy endpoints were changes from baseline in magnetic resonance imaging (MRI) score, EuroQOL‐5 dimensions (EQ‐5D) index score, EQ‐5D pain/discomfort dimension score and C‐reactive protein (CRP, mg/L) level in all PAO patients through week 52. Data from both guselkumab groups were combined and presented as results for a single overall guselkumab group.

Results

Among 159 patients with PPP, 66 with PAO were randomized across treatment groups. For patients with MRI data for all regions assessed, the proportion of patients in the guselkumab group with PAO characterized as severe decreased from 23.8% (10/42) at baseline to 5.4% (2/42) at week 52. The mean (SD) change from baseline at week 52 in EQ‐5D index score was 0.20 (0.17) among PPP patients with PAO and 0.15 (0.17) among those without PAO in the guselkumab group. Among all PAO patients, the proportions with an EQ‐5D pain/discomfort dimension score of no or slight pain/discomfort in the guselkumab group increased from baseline to week 52 [33.3% (7/21) vs. 87.5% (35/40)]. The mean (SD) CRP levels decreased in all PAO patients in the guselkumab group at week 52 compared to baseline [−1.71 (8.16) mg/L].

Conclusion

Guselkumab treatment showed beneficial outcomes for PAO signs and symptoms in Japanese patients with PPP.

Palmoplantar pustulosis: Current understanding of disease definition and pathomechanism

Pustulosis palmaris et plantaris, or palmoplantar pustulosis (PPP), is a chronic pustular dermatitis involving the palms and soles and is characterized by vesicles, pustules, erythema, lichenification, and abnormal desquamation. It is one of the most common skin diseases in Japan but its pathomechanism is unclear and the disease remains poorly defined. Consequently, adequate treatment for PPP is lacking. As a localized type of pustular psoriasis, PPP has long been treated with the conventional therapies used for plaque-type psoriasis, especially in Western countries. However, PPP may be a distinct entity, with a much lower prevalence in Western countries than in Japan. Furthermore, while treatment has yielded insights into the underlying pathology in plaque-type psoriasis, the pathogenesis of PPP has yet to be elucidated. In 2018, Gulselkumab, a monoclonal antibody against interleukin (IL)-23, was certified for use in Japan and is the first biologic effective in PPP both in Japanese and other patients. In this review, we summarize the current understanding of PPP, including the revised definition and possible pathomechanism. The information presented herein provides a more complete picture of PPP and may facilitate the development of improved treatment options.