Pustular Psoriasis: From Pathophysiology to Treatment

Indian expert Delphi consensus on the diagnosis and management of flares of generalised pustular psoriasis

Generalised pustular psoriasis (GPP) is a chronic, multisystemic, autoinflammatory disease with predominantly cutaneous manifestations, characterised by recurrent episodes of widespread, macroscopic and aseptic pustules. It has a highly unpredictable, heterogeneous and unstable clinical course. There are no consensus guidelines in India for the management of GPP. The objective of this Delphi panel study was to achieve consensus on problem areas in the understanding and management of GPP. Based on the inputs from an expert panel, 19 topics across six domains were identified as being important regarding the understanding and management of GPP. Statements were developed for these 19 topics, and consensus for the statements was sought using the modified Delphi method. Twelve experts evaluated the statements, indicating their agreement or disagreement. Consensus was considered to be reached when ≥80% of experts agreed with a statement. After two rounds of discussion, consensus was reached for 17 out of 19 (89%) statements and no consensus was achieved for two (11%) statements. We have presented the statements along with the respective degrees of consensus. Wherever relevant, clarifications or additional comments by experts are provided in the document.

Psoriasis: Perspectives from Irwin M. Braverman, MD

Dr Irwin M. Braverman is recognized as an expert on many skin diseases, including psoriasis, an immune-mediated disorder that presents with scaly erythematous plaques. The most common clinical subtype is plaque psoriasis, with scalp, inverse, guttate, pustular, and nail psoriasis representing additional subtypes. Psoriasis has been associated with several comorbidities, particularly psoriatic arthritis, which affects up to 30% of those with psoriasis. Psoriasis can have an enormous impact on patients, and Dr Braverman reflects that "it is hard to think of another disease that can be so destructive or impactful." Over the course of his career, Dr Braverman treated many patients with psoriasis and observed several significant therapeutic advances, including the widespread use of psoralens with UV-A phototherapy and the introduction of methotrexate. He also contributed to research on the pathophysiology of psoriasis, studying the hallmark dilated capillary loops. Dr Braverman ultimately believes that "taking care of a patient with psoriasis goes into the making of a dermatologist."

Rapid improvement in refractory acrodermatitis continua of Hallopeau with spesolimab injection

We present the case of a patient with acrodermatitis continua of Hallopeau (ACH) who was resistant to traditional therapies such as acitretin, ciclosporin and methotrexate, as well as secukinumab and ustekinumab, who was successfully treated with subcutaneous spesolimab, resulting in rapid resolution of skin lesions.

Literature review and expert opinion on diagnosis and current management of generalized pustular psoriasis

INTRODUCTION

Generalized pustular psoriasis (GPP) is a rare, chronic, systemic, autoinflammatory disease characterized by the eruption of sterile pustules, often accompanied by more general symptoms, such as fever, fatigue, and a burning sensation in the skin. GPP can be potentially life-threatening, if untreated, as it can lead to complications, such as sepsis and heart failure.

AREAS COVERED

In this literature review and expert opinion article, we provide an overview of the epidemiology, pathogenesis, clinical presentation, diagnosis, and treatment of GPP. Eleven dermatologists representing seven different Italian regions considered relevant evidence in the literature to discuss the current diagnosis and treatment of GPP. The expert panel of dermatologists identified several weaknesses in the current clinical management of GPP.

EXPERT OPINION

There is an inconsistent definition and classification of the disease across the literature, which can lead to misdiagnosis and delay in disease treatment. Furthermore, there are no international and standardized clinical guidelines on disease management, especially in Europe. There is a profound need for the development of novel therapeutic agents with sustained efficacy to decrease the impact of the comorbidities and mortality associated with GPP, prevent the onset of complications, and support the unmet needs of these patients.

Real-Life Analysis of Therapeutic Management and Its Correlation with the Dermatology Life Quality Index Score in 108 Patients with Pustular Psoriasis: An Italian Monocenter Study

INTRODUCTION

Pustular psoriasis (PP) is a rare life-threatening skin disease with negatively impact on quality of life (QoL). Clinically, it may be systemic (generalized pustular psoriasis [GPP]) or localized on palms and soles (palmoplantar pustulosis [PPP]). It is not rare to observe plaque psoriasis associated with GPP.

OBJECTIVES

We explored the therapies used for PP and their correlation with patient QoL scores, through a cross-sectional study using retrospective data from a monocentric database in the period 2017-2021.

METHODS

Patient characteristics were summarized using descriptive statistics and treatment predictors of QoL were identified by multiple regression analysis. Among 108 patients with PP, 57.4% had GPP + PSO whereas 42.6% had PPP. The therapeutic management is based on systemic conventional treatments and biological therapies in both GPP and PPP.

RESULTS

GPP + PSO patients with an impaired QoL (DLQI≥10) were associated with biological therapy including certolizumab (odds ratio [OR]=2.38), etanercept (OR=2.25), secukinumab (OR=2.03) or ustekinumab (OR=2.79) whereas, PPP patients were positively associated with secukinumab (OR=2.85) or apremilast (OR 4.28, 95%-CI 0.56-9.62).

CONCLUSIONS

Currently, systemic conventional therapy remains the therapeutic fulcrum of PP management. A great effect on QoL, especially for GPP+PSO, was assessed regardless the ongoing treatment and only newer biologic options were able to somehow positively impact.

Profiling CARD14 gene expression in Indian Psoriasis patients

Several Genome Wide linkage Studies on psoriasis performed to gain insight of genetic architecture of the disease. Caspase Recruitment Domain-containing family 14 (CARD14) also known as CARMA2 or BIMP2; cytogenic location: 17q25.3, is a scaffold protein that primarily controls the skin epidermis's nuclear factor kB (NF-kB) signaling pathway activity in skin epidermis, a master gene for inflammation, has been shown to be linked with rare, heritable form of psoriasis. CARD14 is predominantly expressed in keratinocytes and epithelial cells, but also in unidentified dermal cells. For better understanding of molecular processes involved in CARD14 underlying Indian psoriatic patients, we analyzed gene expression of 42 moderates to severe cases of plaque psoriasis and same number of controls using qPCR and its validation through Immunohistochemistry (IHC). This study identifies that the expression of CARD14 in dermal endothelial cells among patients with psoriasis and explores the potential functional consequences associated with an overactive CARD14 gene. Furthermore, the expression data from the western population was consistent with the results of the qPCR validation of the candidate gene. There is a significant correlation between Indian psoriasis vulgaris patients and CARD14 up-regulation, as evidenced by a roughly two-fold shift in lesional tissue expression. This provides insights into the pathways and genes linked to the pathogenesis of psoriasis.

A Non-Interventional, Multicenter Study to Characterize the Socio-Demographics, Clinical Characteristics, and Management of Generalized Pustular Psoriasis Patients in Spain: IMPULSE Study

INTRODUCTION

Generalized pustular psoriasis (GPP) is a chronic, rare, and potentially life-threatening skin condition characterized by flares comprising widespread sterile pustules and systemic inflammation. Both the rarity and heterogeneity of the disease have made GPP classification and standardization of clinical criteria challenging. Before the approval of spesolimab (IL-36R antibody) in 2022, there were no approved treatments in the USA or Europe for GPP flares. Treatment for GPP has amounted to off-label use of medicines approved to treat plaque psoriasis. Our aim was to describe the sociodemographics, clinical characteristics, and treatment patterns of patients with GPP in Spain.

METHODS

Non-interventional, descriptive, multi-center, retrospective chart review of patients diagnosed with GPP in Spain.

RESULTS

56 patients (50% women) were included, with a mean (standard deviation, SD) age at diagnosis of 53.7 (20.5) and a mean (SD) time of follow-up of 3.7 (3.1) years. In 80% of patients, GPP diagnosis was associated with a flare and 67.3% had known risk factors for GPP (such as previous diagnosis or family history of plaque psoriasis, comorbidities, smoking or stress). Hypertension and plaque psoriasis were the most frequent comorbidities (44.6% each). The number of GPP flares per patient-year was 0.55 with (range 0-4) a mean (SD) body surface area involvement of 21.3% (19.1). The most frequent manifestations of GPP flares were pustules (88.5%), erythema (76.9%), and scaling (76.9%). Additionally, 65.4% of patients had plaque psoriasis, 53.8% had unspecified skin lesions, and 30.8% experienced pain. The treatments used for GPP flares were off-label conventional systemic drugs (75%), mostly corticosteroids, cyclosporine, and acitretin. In the periods between flares, off-label biologics were used in 56.5% of patients. During the study period, 9 patients (16.1%) had at least one complication and 5 of them required hospitalization.

CONCLUSION

This is the first multicenter study in Spanish GPP patients. Most patients were in their fifties, with personal or family history of plaque psoriasis, stress, smoking and a wide range of comorbidities and complications. Even though the number of flares per patient/year was 0.55, there was variability between patients. Both off-label conventional systemics and off-label biologics were used for flare management without a clear treatment pattern.

New and Emerging Treatments for Generalized Pustular Psoriasis: Focus on IL-36 Receptor Inhibitors

Generalized Pustular Psoriasis (GPP) is a rare and severe subtype of psoriasis that significantly impacts patients' quality of life. Until recently, no specific treatment modalities were available, and treatment for GPP followed the guidelines for the treatment of plaque psoriasis, consisting of conventional treatments, such as retinoids, methotrexate, and even biologics, which although effective in some cases, may be associated with significant side effects, necessitating more effective and safe options. The pathophysiology of Generalized Pustular Psoriasis is complex and not fully understood, but there is some overlap with the pathogenesis of Plaque Psoriasis. In GPP, the innate immune system seems to play a more significant role, with the interleukin (IL)-36 pathway being fundamentally involved. Spesolimab and imsidolimab, two recently developed therapeutic agents, target the IL-36 inflammatory pathway by binding to the IL-36 receptor (IL-36R). Both biologics have already been evaluated in phase 1 and 2 clinical trials and have shown promising results in terms of safety and efficacy. IL-36 receptor inhibitors demonstrated great efficacy and good safety profile in the management of patients with GPP, demonstrating their potential to emerge as a leading treatment option. This review aims to explore and summarize the current scientific literature on the most recently developed treatments for GPP.

Novel pharmacotherapies and breakthroughs in psoriasis treatment: 2024 and beyond

INTRODUCTION

The use of the current available therapies for psoriasis management may sometimes be limited by reduced patients' compliance, safety issues for patients' comorbidities, primary lack of efficacy, loss of effectiveness, development of side effects. In this context, several clinical trials investigating the use of both topical and systemic therapies are ongoing, and other new drugs will be approved soon.

AREAS COVERED

The aim of this manuscript is to review current literature and to provide an overview of the current and future trends in psoriasis treatment. A comprehensive review of the English-language medical literature was performed using Pubmed and clinicaltrials.gov databases.

EXPERT OPINION

Although several therapies are currently available for psoriasis' treatment, unmet needs still exist for patients with moderate and severe psoriasis and hence expanding the therapeutic armamentarium is desirable for a more personalized approach. The ongoing development of innovative therapies could provide effective and safe therapies in the future enhancing the therapeutic management of moderate-severe unresponsive psoriasis.

Associations of inflammatory cytokines with palmoplantar pustulosis: a bidirectional Mendelian randomization study

Background

Variations in circulatory cytokine levels have been observed during the onset and course of palmoplantar pustulosis (PPP); however, whether these changes are due to etiological or secondary factors is unclear. To clarify the causal relationship, we conducted a summarized-level bidirectional Mendelian randomization (MR) analysis in this study.

Methods

A FinnGen biobank genome-wide association study (GWAS) of 212,766 individuals (524 PPP patients and 212,242 controls) provided summary data for PPP, whereas genetic instrumental variables (IVs) linked to circulation cytokine levels were gathered from a GWAS of 14,824 European individuals. The inverse-variance weighted (IVW), weighted median (WME), simple mode, and MR-Egger methods were used to ascertain the changes in PPP pathogenic cytokine taxa. Sensitivity analysis, which included horizontal pleiotropy analysis, was then conducted. The reliability of the results was assessed using the leave-one-out approach and the MR Steiger test, which evaluated the strength of a causal relationship. To evaluate the reverse causality between PPP and circulating cytokine levels, a reverse MR analysis was carried out.

Results

Our study demonstrated positive associations between C-X-C motif chemokine 6 (CXCL6) and PPP (odds ratio, OR 1.257, 95%CI: 1.001-1.570, p = 0.043). C-C motif chemokine 19 (CCL19) and interleukin-6 (IL-6) were suggested to be protectively associated with the development of PPP (OR: 0.698,95% CI: 0.516-0.944, p = 0.020; OR: 0.656, 95%CI:0.437-0.985, p = 0.042). The results were steady after sensitivity and heterogeneity analyses.

Conclusion

At the genetic prediction level, we identified causally connected inflammation-related variables that contributed to the onset and development of PPP. The therapeutic options for some refractory PPP have expanded due to tailored cytokine therapy, generating fresh concepts for PPP diagnostics and mechanism investigation.

Epidemiology, Characteristics of Disease, and Unmet Needs of Patients with Generalized Pustular Psoriasis: A Large Italian Delphi Consensus

INTRODUCTION

Generalized pustular psoriasis (GPP) is a rare and chronic, debilitating skin condition characterized, in its acute flare phase, by clinically severe and potentially life-threatening systemic manifestations. Data on GPP are still scanty, particularly in Europe and at a national level. The aim of this study was to provide expert indications on several disease-related and patient-related aspects of GPP, with specific focus to the Italian context.

METHODS

We conducted an iterative eDelphi study following the recommended criteria for reporting methods and results. After a thorough bibliographic review aimed to identify unknown or controversial issues in GPP, the following areas were investigated through a few specific questions/statements for each area: (1) disease epidemiology; (2) disease characteristics, with specific interest toward GPP flares; (3) diagnosis and diagnostic delay; (4) GPP treatment; (5) GPP patient journey and use of healthcare resources in Italy; (6) unmet needs and quality of life. An Executive Board of 9 principal investigators revised and approved the topics to be examined and overviewed the whole project. A total of 35 experts from different Italian areas, including 34 board-certified Italian dermatologists and 1 representative of patients' associations, took part in the study.

RESULTS

A high agreement in responses from Italian experts emerged during two eDelphi iterations on - among several other aspects - GPP prevalence and incidence in Italy, use of European Rare and Severe Psoriasis Expert Network diagnostic criteria, flare frequency and duration, best diagnostic and care pathway, and main unmet needs of Italian patients. On the other hand, a broad spectrum of treatments (of different drug classes) was reported both in the acute and chronic phases of GPP, and no consensus on the issue was thus achieved.

CONCLUSIONS

Consensus findings from this Delphi study of GPP experts may be useful to fill gaps of knowledge and improve awareness of this rare disease, as well as to help clinical and public health management of GPP in Italy.

Case report: Successful treatment with biologics in a pediatric patient with a severe inflammatory skin disease and novel CARD14 mutation

CARD14 (caspase activation and recruitment domain) mutations have been associated with psoriasis vulgaris, psoriatic arthritis, generalized and palmoplantar pustular psoriasis, pityriasis rubra pilaris, and atopic dermatitis. We present a pediatric patient with a novel CARD14: c.394A > T/- (Ile123Phe) mutation, diagnosed with CARD14-associated papulosquamous eruption (CAPE), who was successfully treated with biological treatment.

Better efficacy, lower recurrence rate and decreased CD8+TRM with guselkumab treatment for generalized pustular psoriasis: A prospective cohort study from China

Generalized pustular psoriasis (GPP) is a severe and uncommon form of psoriasis, for which treatment options are limited. There is an urgent need to expand the treatment options for GPP. Currently, adalimumab, secukinumab, and guselkumab are considered effective for GPP, but there is a lack of prospective direct comparative studies on their efficacy for GPP. We conducted a prospective, single-center, observational study on 50 GPP patients to compare the efficacy, safety, and recurrence rates of these three biologics. Adalimumab, secukinumab, and guselkumab resulted in varying degrees of improvement in patients with GPP, but guselkumab exhibited superior efficacy and a lower recurrence rate than the other two drugs. This enhanced response may be attributed to the significant reduction in CD8+ tissue-resident memory T cells within GPP lesions caused by guselkumab.

A case of refractory generalized pustular psoriasis treated with upadacitinib

Here we report a case of upadacitinib in the treatment of generalized pustular psoriasis complicated with psoriatic arthritis. We chose upadacitinib after the use of acitretin did not work well, and achieved a tremendous therapeutic effect. Upadacitinib not only relieved the joint symptoms and fever, but also played a good role in the regression of pustules. At present, there are no successful cases of Janus kinase inhibitor use in the treatment of generalized pustular psoriasis.

New Insights in Psoriasis Management using Herbal Drug Nanocarriers

Psoriasis (Pso) is an autoimmune inflammatory skin disease characterized by red plaques covered in silver scales. The existing treatments provide limited benefits and are associated with certain drawbacks which limit their use. Thus, there is a need to explore more options that are highly target-specific and associated with minimal side effects. Researchers have thoroughly investigated the use of herbal drugs for their therapeutic potential. Preclinical studies demonstrate that phytochemicals such as curcumin, psoralen, and dithranol have antipsoriatic effects. These phytoconstituents inhibit the signalling pathways, such as the interleukin (IL) 23/Th17 axis and IL-36 inflammatory loop involved in the pathogenesis of Pso. These phytoconstituents down-regulate the pro-inflammatory cytokines like IL-17 and tumor necrosis factor (TNF)-α. However, their application in clinical settings is limited due to poor bioavailability and access to target sites. Combining phytoconstituents with modern delivery platforms like nanocarriers can address these shortcomings and improve therapeutic efficacy. This review explores the potential of herbal remedies as a substitute for conventional therapies, emphasizing the clinical trials conducted with these herbal medicines. The paper is supported by the discussion on nanocarriers like liposomes, niosomes, emulsomes, ethosomes, nanostructured lipid carriers, nanoemulsions, and dendrimers that are used to deliver herbal medicines.

Spesolimab for the Treatment of Generalized Pustular Psoriasis

Generalized pustular psoriasis (GPP) is a rare but severe skin inflammatory disorder characterized by the eruption of widespread sterile neutrophilic pustules, often accompanied by systemic inflammation. Given its life-threatening potential, GPP requires prompt accurate diagnosis and effective treatment, but its rarity and relapsing-remitting nature pose challenges in performing large-scale randomized controlled clinical trials. Established international guidelines are currently lacking and management guidance often follows that for plaque psoriasis. However, while it can co-exist with plaque psoriasis and has traditionally been classified as a most severe form of psoriasis, GPP is now recognized as a distinct entity, with its own clinicopathological, autoinflammatory, immunologic and genetic features. Research conducted over the past decade revealed that an imbalance of interleukin (IL)-36 signaling favoring the proinflammatory activity is the central driver of the pathogenesis of GPP, thereby laying the groundwork for the development of targeted therapies for the disease. This article reviews the evidence thus far on spesolimab, a selective humanized antibody against the IL-36 receptor that was recently licensed in Europe and the United States for the treatment of GPP flares in adults. In phase II, randomized controlled clinical trials, spesolimab led to rapid and effective skin clearance in patients experiencing a GPP flare and demonstrated superiority to placebo in preventing flares for up to 48 weeks with maintenance treatment, with reassuring safety and tolerability profiles. Spesolimab is considered to be a first-in-class medication establishing itself as the standard of care for the treatment of GPP flares, thus changing the paradigm of the management of GPP to a new era of scientifically- and evidence-based targeted therapy for this distinctive disease.

Discovery of natural bispecific antibodies: Is psoriasis induced by a toxigenic Corynebacterium simulans and maintained by CIDAMPs as autoantigens?

The high abundance of Corynebacterium simulans in psoriasis skin suggests a contribution to the psoriasis aetiology. This hypothesis was tested in an exploratory study, where western blot (WB) analyses with extracts of heat-treated C. simulans and psoriasis serum-derived IgG exhibited a single 16 kDa-WB-band. Proteomic analyses revealed ribosomal proteins as candidate C. s.-antigens. A peptidomic analysis unexpectedly showed that psoriasis serum-derived IgG already contained 31 immunopeptides of Corynebacteria ssp., suggesting the presence of natural bispecific antibodies (BsAbs). Moreover, peptidomic analyses gave 372 DECOY-peptides with similarity to virus- and phage proteins, including Corynebacterium diphtheriae phage, and similarity to diphtheria toxin. Strikingly, a peptidomic analysis for human peptides revealed 64 epitopes of major psoriasis autoantigens such as the spacer region of filaggrin, hornerin repeats and others. Most identified immunopeptides represent potential cationic intrinsically disordered antimicrobial peptides (CIDAMPs), which are generated within the epidermis. These may form complexes with bacterial disordered protein regions, representing chimeric antigens containing discontinuous epitopes. In addition, among 128 low-abundance immunopeptides, 48 are putatively psoriasis-relevant such as epitope peptides of PGE2-, vitamin D3- and IL-10-receptors. Further, 47 immunopeptides originated from tumour antigens, and the endogenous retrovirus HERV-K. I propose that persistent infection with a toxigenic C. simulans initiates psoriasis, which is exacerbated as an autoimmune disease by CIDAMPs as autoantigens. The discovery of natural BsAbs allows the identification of antigen epitopes from microbes, viruses, autoantigens and tumour-antigens, and may help to develop epitope-specific peptide-vaccines and therapeutic approaches with antigen-specific regulatory T cells to improve immune tolerance in an autoimmune disease-specific-manner.

Atezolizumab-Induced Acrodermatitis and Pustular Psoriasis in a Patient with Non-Small Cell Lung Cancer: A Rare Case Report

Introduction

Immune checkpoint inhibitors are new drugs approved for the treatment of many types of malignancies. Despite their wide use and unquestionable clinical benefits, these agents have also been associated with a unique spectrum of side effects known as immune-related adverse events. In this study, we report the first case of atezolizumab-induced pustular psoriasis and acrodermatitis.

Case Presentation

A 61-year-old woman presented to our department with erythematous-desquamative and pustular lesions involving all hands and feet fingers, inguinal region, and trunk, associated to severe psoriatic onychodystrophy. She was affected by non-small-cell lung carcinoma from 12 years, and 7 months before admission, she started a treatment with atezolizumab.

Conclusion

Immune checkpoint inhibitors such as atezolizumab are linked to a plethora of adverse events. Identifying and treating certain adverse skin events, particularly in cancer patients, can be a challenge, leading oncologists to discontinue immunotherapy. Our case shows how it is necessary to have a shared therapeutic algorithm in order to manage serious skin reactions in cancer patients and avoid disruption of the oncotherapy.

Autoinflammatory Keratinization Diseases-The Concept, Pathophysiology, and Clinical Implications

Recent advances in medical genetics elucidated the background of diseases characterized by superficial dermal and epidermal inflammation with resultant aberrant keratosis. This led to introducing the term autoinflammatory keratinization diseases encompassing entities in which monogenic mutations cause spontaneous activation of the innate immunity and subsequent disruption of the keratinization process. Originally, autoinflammatory keratinization diseases were attributed to pathogenic variants of CARD14 (generalized pustular psoriasis with concomitant psoriasis vulgaris, palmoplantar pustulosis, type V pityriasis rubra pilaris), IL36RN (generalized pustular psoriasis without concomitant psoriasis vulgaris, impetigo herpetiformis, acrodermatitis continua of Hallopeau), NLRP1 (familial forms of keratosis lichenoides chronica), and genes of the mevalonate pathway, i.e., MVK, PMVK, MVD, and FDPS (porokeratosis). Since then, endotypes underlying novel entities matching the concept of autoinflammatory keratinization diseases have been discovered (mutations of JAK1, POMP, and EGFR). This review describes the concept and pathophysiology of autoinflammatory keratinization diseases and outlines the characteristic clinical features of the associated entities. Furthermore, a novel term for NLRP1-associated autoinflammatory disease with epithelial dyskeratosis (NADED) describing the spectrum of autoinflammatory keratinization diseases secondary to NLRP1 mutations is proposed.

Generalized pustular psoriasis: practical recommendations for Spanish primary care and emergency physicians

Generalized pustular psoriasis (GPP) is a rare chronic inflammatory skin disease that can lead to life-threatening complications and require emergency medical treatment. Recurrent GPP flares are characterized by the sudden onset of widespread erythematous skin rash with sterile pustules, at times associated with fever, chills, general malaise, and other systemic inflammatory manifestations. Systemic complications such as cardiorespiratory failure, infections, and sepsis are potentially life-threatening and can result in an emergency department visit and/or hospitalization. Acute GPP episodes can be difficult to recognize and diagnose. The low incidence of the disease, its relapsing nature, the unpredictability of flare onset, and the lack of standardized diagnostic criteria are major obstacles to achieving rapid recognition and diagnosis in both the emergency department and the hospital setting.There is scarce evidence supporting the efficacy and safety of treatments commonly used for GPP; consequently, there is an unmet need for therapies that specifically target the condition. Our aim is to present a multidisciplinary approach to GPP to achieve a rapid diagnosis ensuring that the patient receives the most appropriate treatment for their pathology. The main recommendation for primary care and emergency physicians is to contact a dermatologist immediately for advice or to refer the patient when GPP or a flare is suspected.

Acrodermatitis continua of Hallopeau and generalised pustular psoriasis: Should they be the same or different entities?

Pustular psoriasis is characterised by eruptions of neutrophilic sterile pustules. The European Rare and Severe Psoriasis Expert Network consensus defines pustular psoriasis into three subtypes; generalised pustular psoriasis (GPP), palmoplantar pustulosis and acrodermatitis continua of Hallopeau (ACH). Mixed forms are categorised according to their predominant features. However, the Japanese Dermatological Association includes ACH under the diagnosis of GPP. This article aims to review the similarities and differences between ACH and GPP. Based on our review, interleukin (IL)-36RN mutations, the most frequent genetic findings in pustular psoriasis are found most commonly in GPP, followed by ACH. Genotypes of IL-36RN mutations among GPP patients and ACH patients are different between European and Asian ethnicities. IL-36 signalling pathway is the main mechanism. Metabolic diseases are common comorbidities and joint involvement can occur in 20.5%-36.4% of both conditions. Associated plaque psoriasis is more common in GPP than in ACH. Generally, ACH, even the generalised type, does not have systemic inflammation whereas GPP can occur with or without systemic inflammation. ACH can occur before, simultaneously, or after the development of GPP. However, response to treatment for GPP and ACH even in the same patients appear to be different. ACH seemed to be more recalcitrant to treatment than GPP but severe flare of GPP can lead to morbidity and mortality. Although GPP and ACH share genotypes and pathogenesis, we believe that ACH should be classified separately from GPP, and not under diagnosis of GPP. Future research is warranted to satisfactorily distinguish the two conditions.

The Genetic Susceptibility to Psoriasis and the Relationship of Linked Genes to Our Treatment Options

Understanding the factors creating genetic susceptibility in psoriasis may provide a basis for improving targeted treatment strategies. In this review, we discuss the genes linked to the pathogenesis of psoriasis and their relationship to the available treatment options. To identify the relevant genetic markers and treatments, we searched PubMed, Google Scholar, MEDLINE, and Web of Science with keywords, including genetic susceptibility to psoriasis, genetics and psoriasis, psoriasis treatments, and biologics treatments in psoriasis. The articles in English from database inception to 1/1/23 were included. Case reports and series were excluded. Gene variant forms commonly implicated in the pathogenesis of psoriasis include those encoding for interleukins, interferons, and other mediators involved in inflammatory pathways, such as JAK/STAT, and NF-κB. Several of the treatments for psoriasis (for example IL23 and TYK2 inhibitors) target the products of genes linked to psoriasis. Multiple genes are linked to the pathogenesis of psoriasis. This understanding may provide an avenue for the development of new psoriasis treatment strategies and for more effective, safer treatment outcomes.

Efficacy and safety of spesolimab for the management of generalized pustular psoriasis: a drug safety evaluation

INTRODUCTION

Generalized pustular psoriasis (GPP) is a rare form of psoriasis (less of 1% of cases). Currently, GPP is recognized as a clinical entity, distinguished from plaque psoriasis. However, there are not guidelines for GPP management and treatments are often derived from plaque psoriasis. Therefore, conventional systemic drugs are usually used as first-line treatment options, and biologics are still used off label. Recently, spesolimab, an anti-IL36 receptor humanized IgG1 monoclonal antibody, has been specifically approved for GPP disease, revolutionizing treatment scenario.

AREAS COVERED

The aim of this review is to investigate current literature on the use of spesolimab for GPP management to underline its potential role in GPP and offer a current clinical perspective. Literature research using the Google Scholar, Pubmed, Embase, Cochrane Skin, and clinicaltrials.gov databases was performed, selecting the most relevant manuscripts.

EXPERT OPINION

Spesolimab is efficacious and has a consistent and favorable safety profile in patients presenting with a GPP flare. However, despite excellent results in terms of safety and efficacy have been reported by both clinical trials and very limited real-life experiences, long-term data, especially in flare-up prevention, are scant. Thus, while the available data are encouraging, further research is warranted to understand the efficacy, safety, and long-term outcomes associated with spesolimab treatment in GPP.

Lifetime risk, life expectancy, loss-of-life expectancy, and lifetime healthcare expenditures for psoriasis in Taiwan: a nationwide cohort followed from 2000 to 2017

Background

Patients with psoriasis have a significant disease burden throughout the life course. Nevertheless, the lifetime risk and disease burden of psoriasis across the entire lifespan is rarely quantified in an easily understandable way.

Objective

To estimate the cumulative incidence rate, life expectancy, loss-of-life expectancy, and lifetime healthcare expenditures for incident psoriasis.

Design and methods

Using real-world nationwide data from the National Health Insurance Research Database of Taiwan for 2000-2017, along with the life tables of vital statistics, we estimated cumulative incidence rate, life expectancy, loss-of-life expectancy, and lifetime healthcare expenditures for those with psoriasis using a semi-parametric survival extrapolation method.

Results

A total of 217,924 new psoriasis cases were identified. The lifetime risk of psoriasis in patients aged 18-80 for both sexes decreased in Taiwan with a cumulative incidence rate of 7.93% in 2000 to 3.25% in 2017. The mean (±standard error) life expectancy after diagnosis was 27.11 (± 1.15) and 27.14 (±1.17) years for patients with moderate-to-severe psoriasis and psoriatic arthritis, respectively. Patients with moderate-to-severe psoriasis and psoriatic arthritis had a mean (±standard error) loss-of-life expectancy of 6.41 (±1.16) and 6.48 (±1.17) due to psoriasis, respectively. Male patients have higher lifetime and annual lifetime healthcare expenditures than female. Mean life expectancy, loss-of-life expectancy, and lifetime cost were relatively higher for younger patients.

Conclusion

Among psoriatic patients, patients with moderate-to-severe psoriasis and psoriatic arthritis had substantial years of life lost, particularly for younger patients. Our results provide a reliable estimation of lifetime disease burden, and these estimates will help health authorities in cost-effectiveness assessments of public health interventions and allocation of services resources to minimize loss-of-life expectancy, and lifetime healthcare expenditures in patients with psoriasis.

Characteristics of Patients Experiencing a Flare of Generalized Pustular Psoriasis: A Multicenter Observational Study

Background: Generalized pustular psoriasis (GPP) is a rare, severe inflammatory skin disease characterized by recurrent episodes of flares. Characteristics of patients experiencing a flare are hardly described in a real-life setting. The aim of the study is to investigate the clinical characteristics of patients experiencing a flare of GPP. Methods: Multicenter retrospective observational study on consecutive patients experiencing a flare of GPP between 2018 and 2022. Disease severity and quality of life were assessed by Generalized Pustular Psoriasis Area, Body Surface Area (BSA), and Severity Index (GPPASI), and Dermatology life quality index (DLQI) questionnaire, respectively. Visual analogue scale (VAS) of itch and pain, triggers, complications, comorbidities, pharmacological therapies, and outcome were collected. Results: A total of 66 patients, 45 (68.2%) females, mean age 58.1 ± 14.9 years, were included. The GPPASI, BSA, and DLQI were 22.9 ± 13.5 (mean ± standard deviation), 47.9 ± 29.1, and 21.0 ± 5.0, respectively. The VAS of itch and pain were 6.2 ± 3.3 and 6.2 ± 3.0, respectively. Fever (>38 °C) and leukocytosis (WBC > 12 × 109/L) were found in 26 (39.4%) and 39 (59.1%) patients, respectively. Precipitating triggers were identified in 24 (36.3%) and included infections (15.9%), drugs (10.6%), stressful life events (7.6%), and corticosteroids withdrawal (3.0%). Fourteen (21.2%) patients were hospitalized because of complications including infections in 9 (13.6%) leading to death in one case and hepatitis in 3 (4.5%). Conclusions: GPP flares can be severe and cause severe pain and itch with significant impact on the quality of life. In about one-third of patients the flare may have a persistent course and, with complications, lead to hospitalization.

Acrodermatitis continua of Hallopeau successfully treated with bimekizumab: A case report

Acrodermatitis continua of Hallopeau is a rare variant of localized pustular psoriasis characterized by the recurrent eruption of sterile pustules involving the distal portions of the fingers and toes that can lead to the destruction of the nail apparatus. Acrodermatitis continua of Hallopeau is a chronic, relapsing condition that is resistant to most topical and systemic psoriasis therapies, making it notoriously difficult to manage. Interleukin-36 and interleukin-17 are thought to play a pivotal role in the pathophysiology of pustular psoriasis, and evidence suggests that interleukin-17 inhibition can be an effective therapy for pustular psoriasis variants, including acrodermatitis continua of Hallopeau. Bimekizumab, a monoclonal antibody that inhibits the interleukin-17 pathway, may be a safe and effective treatment option for patients with acrodermatitis continua of Hallopeau. We present the first documented case of a patient with acrodermatitis continua of Hallopeau of the bilateral thumbnails who experienced an excellent response to bimekizumab treatment.

The Intriguing Links between Psoriasis and Bullous Pemphigoid

The coexistence of psoriasis with autoimmune bullous diseases (AIBDs), particularly bullous pemphigoid (BP), has been documented in case reports and series, as well as in epidemiological studies. The onset of psoriasis precedes that of BP in the majority of cases. Patients with concomitant BP and psoriasis are generally younger at the onset of BP and present with fewer erosions and blisters as compared with patients suffering from isolated BP. Intriguingly, it has been speculated that some BP cases with comorbid psoriasis can actually correspond to anti-laminin gamma-1 pemphigoid, a rare form that was recently recognized as a distinct entity and which can mimic BP and/or other subepidermal AIBDs. The pathomechanisms underlying the BP-psoriasis association have not yet been identified, although several hypotheses have been proposed. The most credited among such hypotheses involves the so-called "epitope spreading" phenomenon, with tissue injury secondary to a primary inflammatory process (i.e., psoriasis) leading to the exposure of sequestered antigens evoking a secondary autoimmune disease (i.e., bullous pemphigoid). This narrative review aims to give a brief overview of the association between psoriasis and BP, examining epidemiological, clinical, and immunopathological features, the pathomechanisms underlying this association, the treatments for psoriasis incriminated as potential triggers of BP, and the therapeutic management of patients with psoriasis and BP.

Targeting IL-17A for the treatment of pustular psoriasis: a comprehensive review

INTRODUCTION

Pustular psoriasis (PP) is a rare subtype of psoriasis. Overall, the growing evidence - in particular for acute generalized PP (GPP) - supports that it is a separate entity with a specific pathogenetic pathway. Interleukin (IL)-17/T-helper 17 (Th17) axis involvement may play an important role in the pathophysiology of PP. Biologicals, often required to achieve clinical remission, have changed the treatment of PP.

AREAS COVERED

We provide the reader with an overview of all the available evidence on the use of the antibody-based therapy targeting IL-17A in patients with PP.

EXPERT OPINION

Although papers reported in this review do not provide definitive evidence (due to methodological limitations) to support the use of IL-17 inhibitors as potential first-line for the treatment of PP, based on our own experience and according to most of the reported literature, targeting IL-17A, may represent the best therapeutical approach in this peculiar clinical spectrum of psoriasis.

Pustular psoriasis with a focus on generalized pustular psoriasis: classification and diagnostic criteria. An Italian expert consensus

Generalized pustular psoriasis (GPP) is a severe and life-threatening systemic disease associated with significant morbidity and mortality. Recent progress has been made in understanding the pathogenetic pathways involved in GPP and an intricate interaction between innate and adaptive immune mechanisms has been suggested. Despite formal consensus guidelines on pustular psoriasis currently available in the literature, the definitions and classifications of GPP used across studies were inconsistent. Consequently, there are no unified criteria that can be universally adopted for precise diagnosis, classification and effective treatment of GPP patients with new targeted drugs. The aim of this review was to collect all the main evidence on available diagnostic criteria for GPP and to establish recommendations in order to promote a better stratification and therapeutic management of this severe and heterogeneous disease.

Clinical Characteristics of Patients with Pustular Psoriasis: A Single-Center Retrospective Observational Study

Clinical and epidemiologic data on pustular psoriasis are scarce. To investigate the phenotypes of pustular psoriasis and the patients’ characteristics observed in a real-life retrospective observational study. The number of incident cases of pustular psoriasis registered in the period 2005–2021 was retrieved from the electronic medical records of the University Hospital of Verona. One hundred and forty cases of pustular psoriasis were collected. Ninety-one out of 140 patients (65%) were females, with a median (IQR) age of 57 (43–66) years. According to the ERASPEN classification criteria, 116 patients (83%) had palmoplantar pustulosis (PPP), 13 (9%) generalized pustular psoriasis (GPP), and 11 (8%) acrodermatitis continua of Hallopeau (ACH). Gender distribution and median age were consistent among the three groups. The prevalence of psoriatic arthritis in GPP, ACH, and PPP was 8%, 36%, and 28%, respectively. During the same period, a total of 4718 cases of plaque psoriasis were retrieved, with a 1:34 ratio of pustular over plaque psoriasis. Pustular psoriasis is much rarer than plaque psoriasis, with PPP being the more common subtype.

Beyond plaque psoriasis - pathogenesis and treatment of other psoriasis phenotypes

PURPOSE OF REVIEW

Psoriasis vulgaris is the commonest presentation of psoriatic disease, but morphologic variants such as pustular psoriasis (PP) and a closely related disease, pityriasis rubra pilaris (PRP), have been known for a long time, have been associated with rheumatologic manifestations indistinguishable from psoriatic arthritis (PsA) that may go unrecognized, and often represent a therapeutic conundrum. There is recent evidence that underlying genetic and pathogenetic differences may provide the basis for newer therapeutic approaches.

RECENT FINDINGS

This narrative review highlights the clinical, genetic and pathogenetic characteristics of PP and PRP, their association with PsA and recent developments in their treatment, especially with biologic agents targeting IL-36 and other cytokines of pathogenic relevance.

SUMMARY

The clinical manifestations of PP and PRP are less well known to rheumatologists than those of psoriasis, and recent advances in our insight on their pathogenesis may eventually overcome the therapeutic difficulties faced by dermatologists and rheumatologists in the management of these diseases and their rheumatologic manifestations.

Generalized Pustular Psoriasis in Pregnancy: Current and Future Treatments

Generalized pustular psoriasis (GPP) is a rare, severe neutrophilic skin disease characterized by sudden widespread eruption of sterile pustules with or without systemic symptoms. GPP may be life threatening in cases with severe complications such as cardiovascular failure, acute respiratory distress syndrome, and serious infections. Impetigo herpetiformis (IH) is a GPP that is induced and exacerbated by pregnancy and occurs most frequently during the last trimester. IH may result in poor or fatal neonatal outcomes, including placental insufficiency, fetal abnormalities, stillbirth, and early neonatal death. Most patients have prompt remission in the postpartum period; however, earlier appearance and more severe symptoms are observed during subsequent pregnancies. Appropriate treatment and close monitoring of the mother and fetus are vital for the management of patients with IH. Particular attention is required for the management of patients with IH to avoid an influence on the fetus. However, data regarding treatments for GPP in pregnant women are sparse. Over the last decade, many patients with IH have been treated with cyclosporine, corticosteroids, tumor necrosis factor-α inhibitors, interleukin (IL)-17 and IL-12/23 inhibitors, and granulocyte and monocyte adsorption apheresis (GMA). GMA may be an important option for patients with IH as it is presently one of the safest available therapeutic options, but there have been no reports to fully confirm its safety in pregnant patients with GPP. Alternatively, based on recent advances in the understanding of the role of the IL-36 axis in the pathogenesis of GPP, biologic agents that target the IL-36 pathway may demonstrate promising efficacy in IH.