Clinical response to ustekinumab in familial pityriasis rubra pilaris caused by a novel mutation in CARD14

Biologics for inherited disorders of keratinisation: A systematic review

BACKGROUND/OBJECTIVES

Recent literature highlights the potential of biologics in the management of inherited disorders of keratinisation. In this study, we conducted a systematic review of existing literature on treatment outcomes of inherited keratinisation disorders treated with biologics.

METHODS

Eligible records were retrieved through searches of the electronic databases MEDLINE, Embase, PubMed and Scopus. Databases were searched from inception to July 2023 for eligible records. A snowballing method was employed to search the references of the retrieved records for the identification of potentially relevant articles.

RESULTS

One hundred and four eligible studies consisting of a total of 166 patients with an inherited disorder of keratinisation were included. Patients had a median age of 19 years (range: 0.5 to 70 years). The most common disorders were Netherton syndrome (n = 63; 38%), autosomal recessive congenital ichthyoses (n = 27; 16%), CARD14-associated papulosquamous eruptions (n = 17; 10%) and familial pityriasis rubra pilaris (PRP) (n = 15; 9%).Of the 207 times biologics were employed, the three most frequently employed biologics were secukinumab (n = 47; 23%), dupilumab (n = 44; 21%) and ustekinumab (n = 37; 18%). Complete remission was observed in 10 (5%) instances, partial remission in 129 (62%), no or limited response to biologic therapy in 68 (32%) cases, and results are still pending in one case. A total of 33 adverse events were reported.

CONCLUSIONS

Whilst biologics may be considered in cases of inherited keratinisation disorders recalcitrant to standard therapy, definitive conclusions are prohibited by the low-level of evidence and substantial heterogeneity in methodology across the included studies. Establishment of consensus definitions, and randomised clinical trials may help ascertain the efficacy and safety of biologic therapy in this context and establish the best agent and dosing protocol for each disorder.

Chimeric and mutant CARD9 constructs enable analyses of conserved and diverged autoinhibition mechanisms in the CARD-CC protein family

Caspase recruitment domain-containing protein (CARD)9, CARD10, CARD11, and CARD14 all belong to the CARD-coiled coil (CC) protein family and originated from a single common ancestral protein early in vertebrate evolution. All four proteins form CARD-CC/BCL10/MALT1 (CBM) complexes leading to nuclear factor-kappa-B (NF-κB) activation after upstream phosphorylation by various protein kinase C (PKC) isoforms. CBM complex signaling is critical for innate and adaptive immunity, but aberrant activation can cause autoimmune or autoinflammatory diseases, or be oncogenic. CARD9 shows a superior auto-inhibition compared with other CARD-CC family proteins, with very low spontaneous activity when overexpressed in HEK293T cells. In contrast, the poor auto-inhibition of other CARD-CC family proteins, especially CARD10 (CARMA3) and CARD14 (CARMA2), is hampering characterization of upstream activators or activating mutations in overexpression studies. We grafted different domains from CARD10, 11, and 14 on CARD9 to generate chimeric CARD9 backbones for functional characterization of activating mutants using NF-κB reporter gene activation in HEK293T cells as readout. CARD11 (CARMA1) activity was not further reduced by grafting on CARD9 backbones. The chimeric CARD9 approach was subsequently validated by using several known disease-associated mutations in CARD10 and CARD14, and additional screening allowed us to identify several previously unknown activating natural variants in human CARD9 and CARD10. Using Genebass as a resource of exome-based disease association statistics, we found that activated alleles of CARD9 correlate with irritable bowel syndrome (IBS), constipation, osteoarthritis, fibromyalgia, insomnia, anxiety, and depression, which can occur as comorbidities.

Congenital Ichthyosis: A Practical Clinical Guide on Current Treatments and Future Perspectives

Congenital ichthyoses are a group of hereditary disorders of keratinization that are challenging to treat. Affected individuals suffer not only from thickening of the skin but also associated complications such as growth restriction, hearing and eye complications, infections, and thermodysregulation. This clinical review provides a practical roadmap to the longitudinal care of patients with ichthyosis with both general and age- and disease-specific recommendations. The allure of pathogenesis-based and targeted treatments for these monogenetic severe but orphan conditions shines bright as dermatological therapies enter a new era.

A viewpoint on the genetic determinants of generalised pustular psoriasis

Generalised pustular psoriasis (GPP) is a rare and severe neutrophilic skin disorder, manifesting with acute episodes of pustulation and systemic upset. The discovery of recessive IL36RN mutations associated with GPP has transformed our understanding of disease drivers, paving the way for the development of targeted anti-IL36 therapeutics. In the light of these remarkable successes, this viewpoint reviews the significance of IL36RN mutations in GPP, their functional impact and their correlation with clinical phenotypes. It then covers the discovery of further genetic determinants (recessive MPO mutations) and risk factors (AP1S3 and CARD14 low-frequency variants) for the disease. It discusses the growing evidence for genetic complexity in GPP and concludes by outlining collaborative strategies that may be adopted to overcome the challenges ahead.

Treatment Options for Juvenile Pityriasis Rubra Pilaris

Pityriasis rubra pilaris represents a group of familial and acquired disorders of cornification that affect both adult and pediatric patients. Treatment options are difficult to assess through clinical trials, given the rarity of the disorder and its tendency for spontaneous remission. Case reports and case series are therefore the primary means of assessment. Because of the heterogeneity of the disease, there is no universal approach to treatment, and multiple agents may need to be trialed to achieve disease control. At present, topicals are used for most pediatric patients, though monotherapy with topicals is only effective for less severe disease. Despite concerns over their side-effect profiles, oral retinoids are generally accepted as a first-line systemic therapy. However, interleukin-17 inhibitors and ustekinumab, an interleukin-12 and interleukin-23 inhibitor, may soon become first-line systemic treatment as well, given their efficacy and relative safety in trials thus far. Ustekinumab, in particular, is emerging as a first-line agent for patients with pityriasis rubra pilaris with CARD14 gene variations. When these therapies fail, second-line and adjunctive therapies to consider include tumor necrosis factor-alpha inhibitors, methotrexate, and phototherapy. However, further investigation is necessary to assess the safety and efficacy of many of these agents in juvenile pityriasis rubra pilaris.

Tailored treatments in inborn errors of immunity associated with atopy (IEIs-A) with skin involvement

Inborn errors of immunity associated with atopy (IEIs-A) are a group of inherited monogenic disorders that occur with immune dysregulation and frequent skin involvement. Several pathways are involved in the pathogenesis of these conditions, including immune system defects, alterations of skin barrier and metabolism perturbations. Current technological improvements and the higher accessibility to genetic testing, recently allowed the identification of novel molecular pathways involved in IEIs-A, also informing on potential tailored therapeutic strategies. Compared to other systemic therapy for skin diseases, biologics have the less toxic and the best tolerated profile in the setting of immune dysregulation. Here, we review IEIs-A with skin involvement focusing on the tailored therapeutic approach according to their pathogenetic mechanism.

Cutaneous and Developmental Effects of CARD14 Overexpression in Zebrafish

BACKGROUND

Gain-of-function mutations in CARD14 have recently been shown to be involved in the pathogenesis of psoriasis and pityriasis rubra pilaris (PRP). Those mutations were found to activate the NF-kB signaling pathway.

OBJECTIVE

Zebrafish is often used to model human diseases in general, and in skin disorders more particularly. In the present study, we aimed to examine the effect of CARD14 overexpression in zebrafish with the aim to validate this model for future translational applications.

METHODS

We used light microscopy, scanning electron microscopy, histological analysis and whole mount in situ hybridization as well as real-time PCR to ascertain the effect of CARD14 overexpression in the developing zebrafish.

RESULTS

Overexpression of human CARD14 had a marked morphological and developmental effect on the embryos. Light microscopy demonstrated a characteristic cutaneous pattern including a granular surface and a spiky pigment pattern. In situ hybridization revealed keratinocytes of uneven size and shape. Scanning electron microscopy showed aberrant production of actin microridges and a rugged keratinocyte cell surface, reminiscent of the human hyperkeratotic phenotype. Developmentally, overexpression of CARD14 had a variable effect on anterior-posterior axis symmetry. Similar to what has been observed in humans with psoriasis or PRP, NF-kB expression was higher in CARD14-overexpressing embryos compared to controls.

CONCLUSIONS

Overexpression of CARD14 results in a distinct cutaneous pattern accompanied by hyperactivation of the NF-kB pathway, suggesting that the zebrafish represents a useful system to model CARD14-associated papulosquamous diseases.

New developments in the molecular treatment of ichthyosis: review of the literature

Ichthyosis covers a wide spectrum of diseases affecting the cornification of the skin. In recent years, new advances in understanding the pathophysiology of ichthyosis have been made. This knowledge, combined with constant development of pathogenesis-based therapies, such as protein replacement therapy and gene therapy, are rather promising for patients with inherited skin diseases. Several ongoing trials are investigating the potency of these new approaches and various studies have already been published. Furthermore, a lot of case series report that biological therapeutics are effective treatment options, mainly for Netherton syndrome and autosomal recessive congenital ichthyosis. It is expected that some of these new therapies will prove their efficacy and will be incorporated in the treatment of ichthyosis.

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.

Paraneoplastic Pityriasis Rubra Pilaris Preceding Leukemia

ABSTRACT

Pityriasis rubra pilaris (PRP) is a rare, chronic papulosquamous disorder that presents with scaling plaques, palmoplantar keratoderma, and keratotic follicular papules. Typically, there are distinctive unaffected areas referred to as "islands of sparing." Pityriasis rubra pilaris has been associated with various immunodeficient states and malignancies.The authors conducted a literature review using MEDLINE, PubMed, and Google Scholar, documenting all known cases of PRP associated with malignancy; 15 cases were found in the literature. They also present the case of a 49-year-old White man who, prior to referral to dermatology, was seen in urgent care for widespread pruritic rash. Physical examination in the dermatology clinic revealed confluent, scaly erythematous papules coalescing into plaques with island of sparing involving the trunk and upper and lower extremities. Bilateral palms and soles showed hyperkeratosis with fissuring. He was diagnosed with PRP after punch biopsy and began a new course of topical corticosteroid therapy. Hematology was consulted because of abnormal complete blood count results, and he was subsequently diagnosed with chronic lymphoid leukemia.Treatment of PRP is largely based on clinical experience and may involve corticosteroids, immunomodulators, or biologic therapy. The relationship between PRP and malignancy is unknown. Current theories postulate it may be driven by tumor production of functional peptides or antigen cross-reactivity between cancer cells and the skin. This is the second reported case of PRP as a manifestation of leukemia, and the first of chronic lymphoid leukemia. Although not yet understood, the documented relationship between PRP and malignancy prompts screening for cancer in all patients with new-onset PRP.

Challenges in Treating Genodermatoses: New Therapies at the Horizon

Genodermatoses are rare inherited skin diseases that frequently affect other organs. They often have marked effects on wellbeing and may cause early death. Progress in molecular genetics and translational research has unravelled many underlying pathological mechanisms, and in several disorders with high unmet need, has opened the way for the introduction of innovative treatments. One approach is to intervene where cell-signaling pathways are dysregulated, in the case of overactive pathways by the use of selective inhibitors, or when the activity of an essential factor is decreased by augmenting a molecular component to correct disequilibrium in the pathway. Where inflammatory reactions have been induced by a genetically altered protein, another possible approach is to suppress the inflammation directly. Depending on the nature of the genodermatosis, the implicated protein or even on the particular mutation, to correct the consequences or the genetic defect, may require a highly personalised stratagem. Repurposed drugs, can be used to bring about a "read through" strategy especially where the genetic defect induces premature termination codons. Sometimes the defective protein can be replaced by a normal functioning one. Cell therapies with allogeneic normal keratinocytes or fibroblasts may restore the integrity of diseased skin and allogeneic bone marrow or mesenchymal cells may additionally rescue other affected organs. Genetic engineering is expanding rapidly. The insertion of a normal functioning gene into cells of the recipient is since long explored. More recently, genome editing, allows reframing, insertion or deletion of exons or disruption of aberrantly functioning genes. There are now several examples where these stratagems are being explored in the (pre)clinical phase of therapeutic trial programmes. Another stratagem, designed to reduce the severity of a given disease involves the use of RNAi to attenuate expression of a harmful protein by decreasing abundance of the cognate transcript. Most of these strategies are short-lasting and will thus require intermittent life-long administration. In contrast, insertion of healthy copies of the relevant gene or editing the disease locus in the genome to correct harmful mutations in stem cells is more likely to induce a permanent cure. Here we discuss the potential advantages and drawbacks of applying these technologies in patients with these genetic conditions. Given the severity of many genodermatoses, prevention of transmission to future generations remains an important goal including offering reproductive choices, such as preimplantation genetic testing, which can allow selection of an unaffected embryo for transfer to the uterus.

CARD14-associated papulosquamous eruption (CAPE) in pediatric patients: Three additional cases and review of the literature

CARD14-associated papulosquamous eruption (CAPE) is a proposed term that encompasses features ranging from psoriasis to pityriasis rubra pilaris (PRP) in association with CARD14 mutations. The early onset of the disease, prominent facial involvement, family history of an autosomal dominant trait, and poor response to conventional treatment are characteristics of CAPE that distinguish it from classical psoriasis and PRP. We describe the clinical features, family history, and response to therapy in three unrelated children with CAPE and compare these characteristics with those of previously described pediatric patients. Testing for CARD14 mutations in children with early onset of features of psoriasis or pityriasis rubra pilaris and resistance to conventional therapy should be considered.

Alternative uses of ustekinumab for non-indicated dermatological conditions: a systematic review

Ustekinumab is approved for the treatment of psoriasis and Crohn's disease. Because many dermatological conditions are due to immune-mediated development, ustekinumab may be effective in other conditions. A systematic review of the off-label uses of ustekinumab, as well as on-label adverse effect, was performed, reporting on clinical improvement. MEDLINE, Embase, Web of Science, and Cochrane databases were searched for studies regarding ustekinumab treatment of rativa (HS), lichen planus (LP), pyoderma gangrenosum (PG), pityriasis rubra pilaris (PRP), cutalopecia areata (AA), atopic dermatitis (AD), Bechet's disease, bullous pemphigoid (BP), hidradenitis suppuaneous sarcoidosis, cutaneous systemic lupus erythematosus (SLE), and vitiligo. Descriptive statistics were performed. 74 articles of 4596 screened were included, and reported on 212 patients receiving ustekinumab treatment. Across all studies, ustekinumab showed promise in treating patients: AA (10/12 patients; 83.3% improvement), AD (28/74 patients; 37.8% improvement), HS (42/52 patients; 80.8% improvement), and PRP (25/27 patients; 92.6% improvement), among others. Adverse events were noted with the use of ustekinumab, including development of AA (four patients), AD (three patients), and BP (four patients), among others. Ustekinumab can be a promising option for patients with dermatological conditions refractory to traditional therapies. Adverse events must be monitored in certain patients.

Autoinflammatory keratinitzation diseases (AIKDs

Autoinflammatory keratinization disease (AiKD) is a novel clinical concept encompassing diseases with a genetic background and mixed pathogenic mechanisms of autoinflammation and autoimmunity, leading to an aberrant keratinization of the skin. Recent advances in medical genetics have revealed genetic causes and/or predisposing factors for a number of AiKD's, such as mutations in IL36RN related with pustular psoriasis, acrodermatitis continua and hidradenitis suppurativa, in CARD14 in pityriasis rubra pilaris type V and some forms of pustular psoriasis, and in NLRP1 related with familial keratosis lichenoides chronica (KLC). It is suspected that AiKD pathophysiology would also be involved in non-monogenic disorders. The bidirectional relationship between inflammation and keratinization should be understood in order to outline optimal management, and new drug development should take both targets into account. We assume that new inflammatory keratinization diseases may be recognized as AiKDs in the coming years.

Molecular mechanisms of phenotypic variability in monogenic autoinflammatory diseases

Monogenic autoinflammatory diseases are a group of rheumatologic disorders caused by dysregulation in the innate immune system. The molecular mechanisms of these disorders are linked to defects in inflammasome-mediated, NF-κB-mediated or interferon-mediated inflammatory signalling pathways, cytokine receptors, the actin cytoskeleton, proteasome complexes and various enzymes. As with other human disorders, disease-causing variants in a single gene can present with variable expressivity and incomplete penetrance. In some cases, pathogenic variants in the same gene can be inherited either in a recessive or dominant manner and can cause distinct and seemingly unrelated phenotypes, although they have a unifying biochemical mechanism. With an enhanced understanding of protein structure and functionality of protein domains, genotype-phenotype correlations are beginning to be unravelled. Many of the mutated proteins are primarily expressed in haematopoietic cells, and their malfunction leads to systemic inflammation. Disease presentation is also defined by a specific effect of the mutant protein in a particular cell type and, therefore, the resulting phenotype might be more deleterious in one tissue than in another. Many patients present with the expanded immunological disease continuum that includes autoinflammation, immunodeficiency, autoimmunity and atopy, which necessitate genetic testing.

Identification of a pathogenic CARD14 mutation in a 70-year-old woman with pityriasis rubra pilaris: when genetic diagnosis influences choice of treatment strategy

Pityriasis rubra pilaris (PRP) is a rare dermatosis characterised by hyperkeratotic follicular papules, orange-red scaly plaques and palmoplantar keratoderma. The aetiology of the disease is in most cases unclear and treatment can be challenging. Familial cases of PRP may result from pathogenic variants in the caspase recruitment domain family member 14 (CARD14). We present a case of lifelong PRP in a 70-year-old woman, where genetic testing revealed a heterozygote missense variant c.412G>A, p.(Glu138Lys) in CARD14. Therapy with ustekinumab was initiated with remarkable effect, which improved the patient's quality of life significantly.

Two cases of CARD14-associated papulosquamous eruption from India

Identification of CARD14-associated papulosquamous eruption (CAPE) is important as it helps in determining prognosis and management of those affected. We report two siblings with genetically confirmed CAPE presenting with treatment-resistant erythroderma in one patient and patterned psoriatic plaques with facial predominance in the other.

Histopathologic findings characteristic of CARD14-associated papulosquamous eruption

BACKGROUND

Pathogenic mutations in caspase recruitment domain-containing protein 14 (CARD14) lead to CARD14-associated papulosquamous eruption, which shares clinicopathologic findings with psoriasis and pityriasis rubra pilaris. We aimed to describe distinguishing histopathologic features of CARD14-associated papulosquamous eruption.

METHODS

This retrospective study examined the histopathologic features of specimens from patients with confirmed CARD14-associated papulosquamous eruption and adult patients with plaque psoriasis and pityriasis rubra pilaris.

RESULTS

Lesional skin biopsies from patients with CARD14-associated papulosquamous eruption consistently showed alternating checkerboard parakeratosis and orthokeratosis, acanthosis without acantholysis, and dilated vessels in the dermal papillae, with some cases also showing follicular plugging.

CONCLUSION

CARD14-associated papulosquamous eruption has a range of findings, with a predominance of features typically associated with pityriasis rubra pilaris.

Periodic fever syndromes and the autoinflammatory diseases (AIDs)

Innate immune system represents the ancestral defense against infectious agents preserved along the evolution and species; it is phylogenetically older than the adaptive immune system, which exists only in the vertebrates. Cells with phagocytic activity such as neutrophils, macrophages, and natural killer (NK) cells play a key role in innate immunity. In 1999 Kastner et al. first introduced the term “autoinflammation” describing two diseases characterized by recurrent episodes of systemic inflammation without any identifiable infectious trigger: Familial Mediterranean Fever (FMF) and TNF Receptor Associated Periodic Syndrome (TRAPS). Autoinflammatory diseases (AIDs) are caused by self-directed inflammation due to an alteration of innate immunity leading to systemic inflammatory attacks typically in an on/off mode. In addition to inflammasomopathies, nuclear factor (NF)-κB-mediated disorders (also known as Rhelopathies) and type 1 interferonopathies are subjects of more recent studies.

This review aims to provide an overview of the field with the most recent updates (see “Most recent developments in..” paragraphs) and a description of the newly identified AIDs.

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Autoinflammatory diseases are caused by self-directed inflammation.

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Alteration of innate immunity leads to systemic inflammation attacks.

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The autoinflammatory field is exponentially expanding.

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The advances in AIDs have led to new insights into immune system understanding.

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Autoimmunity and autoinflammation features may be simultaneously present.

Whole exome sequencing approach to childhood onset familial erythrodermic psoriasis unravels a novel mutation of CARD14 requiring unusual high doses of ustekinumab

BACKGROUND

Autosomal dominant gain of function mutations in caspase recruitment domain family member 14 (CARD14) is a rare condition associated with plaque-type psoriasis, generalized pustular psoriasis, palmoplantar pustular psoriasis and pityriasis rubra pilaris. Recently, a new CARD14 -associated phenotype defined as CAPE (CARD14-associated papulosquamous eruption) with clinical features of both psoriasis and pityriasis rubra pilaris was reported. We describe a family carrying a novel heterozygous mutation in CARD14 gene, with childhood-onset erythrodermic psoriasis requiring an unusual extremely high dose (up to 2 mg/kg every 8 weeks) of ustekinumab to achieve disease remission.

CASE PRESENTATION

We describe a large family with three pairs of twins presenting a clinical phenotype characterized by childhood-onset erythrodermic psoriasis; in some family members is also reported psoriatic arthritis. The two probands presented poor clinical response to topic and systemic therapy with antihistamine, steroid, retinoids, cyclosporine and etanercept. After exclusion of the most common genes associated to autoinflammatory diseases (IL36RN, IL1RN, MVK, TNFRSF1A, NLRP3, NLRP12, MEFV, NOD2, PSMB8, PSTPIP1, LPIN2) we approached a new gene search by subjecting to Whole Exome Sequencing (WES) analysis five members of the family. A novel heterozygous mutation (c.446 T > G, leading to the missense amino acid substitution p.L149R) in the exon 4 of the CARD14 gene was identified in all affected members. Increasing dosages (up to 2 mg/kg every 8 weeks) of ustekinumab, a human monoclonal antibody targeting interleukin-12 (IL-12) and interleukin-23 (IL-23), allowed the complete control of the clinical manifestations, with an evident reduction of circulating Th17 and Th22 CD4+ T cell subsets.

CONCLUSIONS

We describe the association of mutations of the CARD14 gene with an erythrodermic psoriasis pedigree, underlying the necessity to investigate CARD14 mutations in childhood-onset psoriasis cases and confirming the presence of CARD14 causative mutations also in erythrodermic psoriasis form, as recently reported. Also in pediatric age, ustekinumab represents a powerful therapeutic option for this rare condition, that is usually refractory to other treatments. In young children, high and frequent dosages allowed a complete control of the clinical manifestations without any severe side effects, with a long-term follow-up.

What's New in Genetic Skin Diseases

The discoveries of new genes underlying genetic skin diseases have occurred at a rapid pace, supported by advances in DNA sequencing technologies. These discoveries have translated to an improved understanding of disease mechanisms at a molecular level and identified new therapeutic options based on molecular targets. This article highlights just a few of these recent discoveries for a diverse group of skin diseases, including tuberous sclerosis complex, ichthyoses, overgrowth syndromes, interferonopathies, and basal cell nevus syndrome, and how this has translated into novel targeted therapies and improved patient care.

The management and genetic background of pityriasis rubra pilaris: a single-centre experience

BACKGROUND

Pityriasis rubra pilaris (PRP) is a rare chronic inflammatory dermatosis with multifactorial aetiology. It is known that particular caspase recruitment domain family member 14 (CARD14) gene mutations are associated with familial PRP and certain forms of psoriasis. Additionally, few data are available about the role of CARD14 gene variants in sporadic PRP. The clinical picture is variable for the different types of PRP, therefore choosing the adequate treatment is often difficult, furthermore there are no specific guidelines for therapy.

OBJECTIVE

Our aim was to survey the efficacy of the applied therapies and to screen the CARD14 gene variants in our PRP patients.

METHODS

In this retrospective study, patients diagnosed with PRP between 2006 and 2016 at our clinic were involved. Besides the follow-up study of the treatments, the genetic analysis of CARD14 gene was performed.

RESULTS

We analysed 19 patients, among whom 17 were diagnosed with type I, one with type III, and one with type V PRP. The majority of the patients were successfully treated with acitretin in combination with systemic corticosteroids, and the remaining patients were treated with other systemic therapies with diverse effects. The genetic screening of CARD14 gene revealed two previously described mutations (rs114688446, rs117918077) and six polymorphisms (rs28674001, rs2066964, rs34367357, rs11653893, rs11652075, rs2289541). Ten of 19 patients carried different CARD14 genetic variants either alone or in combination.

CONCLUSION

Based on our experience, we propose that acitretin and an initial combination of short-term systemic corticosteroid therapy could be a successful treatment option for PRP. Although we identified several CARD14 variants in almost half of our cases, we did not find a correlation between the therapeutic response and the genetic background. Our data support the previous observation that CARD14 genetic variants are not specific to PRP, although they may indicate chronic inflammation.

Systemic therapies of pityriasis rubra pilaris: a systematic review

Pityriasis rubra pilaris (PRP) is a rare papulosquamous disorder. Treatment is challenging; the armamentarium consists of topical corticosteroids, phototherapy, classic systemic treatments such as retinoids or immunosuppressive drugs, and most recently biologicals. However, the relative effectiveness of therapies is unclear. Our objective was to review the published literature on systemic treatment of PRP. A systematic review was conducted on PubMed and the Cochrane Library up to 5 September 2017. Studies evaluating any systemic treatments of PRP (except for historical treatments) were included. Overall, 182 studies met the predefined inclusion criteria, and reported on 475 patients and 652 courses of treatment. 42.0 % (225/514) of all patients treated with retinoids achieved an excellent response (isotretinoin: 61.1 % [102/167], etretinate: 47 % [54/115], and acitretin: 24.7 % [43/174]) compared to an excellent response rate of 33.1 % (53/160) with methotrexate. Therapy with biologicals was successful in 51.0 % of patients (71/133) (ustekinumab: 62.5 % [10/16], infliximab: 57.1 % [28/49], etanercept: 53.3 % [16/30], and adalimumab: 46.4 % [13/28]). This review balances effectiveness, side effects, experience, and drug costs in order to suggest a treatment regimen starting with isotretinoin as first-line, methotrexate as second-line and biologicals as third-line treatment for this difficult-to-treat dermatosis.

CARD14/CARMA2 Signaling and its Role in Inflammatory Skin Disorders

CARMA proteins represent a family of scaffold molecules which play several crucial biological functions, including regulation of immune response and inflammation, tissue homeostasis, and modulation of G-Protein Coupled Receptor (GPCR) signaling. Among the CARMA proteins, CARD14/CARMA2 and its alternatively spliced isoforms are specifically expressed in epithelial cells and keratinocytes. Recent evidences have shown that CARD14/CARMA2 mediates induction of inflammatory response in keratinocytes, and that mutations in CARD14/CARMA2 gene segregate with familial transmission of chronic inflammatory disorders of the human skin. Similarly to CARD11/CARMA1 and CARD10/CARMA3, CARD14/CARMA2 signaling occurs trough formation of a trimeric complex which includes BCL10 and MALT1 proteins. However, it is becoming increasingly evident that in addition to the CBM complex components, a number of accessory molecules are able to finely modulate the signals conveyed on and amplified by CARD14/CARMA2. The study of these molecules is important both to understand the molecular mechanisms that underlie the role of CARMA2 in keratinocytes and because they represent potential therapeutic targets for the development of therapeutic strategies aiming at the treatment of inflammatory diseases of the human skin. In this review, we provide an overview on the molecular mechanisms mediating CARD14/CARMA2 signaling and its implication in our understanding of the pathogenesis of human inflammatory skin disorders.

Caspase recruitment domain (CARD) family (CARD9, CARD10, CARD11, CARD14 and CARD15) are increased during active inflammation in patients with inflammatory bowel disease

Background

The CARD family plays an important role in innate immune response by the activation of NF-κB. The aim of this study was to determine the gene expression and to enumerate the protein-expressing cells of some members of the CARD family (CARD9, CARD10, CARD11, CARD14 and CARD15) in patients with IBD and normal controls without colonic inflammation.

Methods

We included 48 UC patients, 10 Crohn’s disease (CD) patients and 18 non-inflamed controls. Gene expression was performed by RT-PCR and protein expression by immunohistochemistry. CARD-expressing cells were assessed by estimating the positively staining cells and reported as the percentage.

Results

The CARD9 and CARD10 gene expression was significantly higher in UC groups compared with CD (P < 0.001). CARD11 had lower gene expression in UC than in CD patients (P < 0.001). CARD14 gene expression was higher in the group with active UC compared to non-inflamed controls (P < 0.001). The low expression of CARD14 gene was associated with a benign clinical course of UC, characterized by initial activity followed by long-term remission longer than 5 years (P = 0.01, OR = 0.07, 95%CI:0.007–0.70). CARD15 gene expression was lower in UC patients versus CD (P = 0.004). CARD9 protein expression was detected in inflammatory infiltrates; CARD14 in parenchymal cells, while CARD15 in inflammatory and parenchymal cells. CARD9−, CARD14− and CARD15 − expressing cells were significantly higher in patients with active UC versus non-inflamed controls (P < 0.05).

Conclusion

The CARD family is involved in the inflammatory process and might be involved in the IBD pathophysiology.

A Review on Pityriasis Rubra Pilaris

Pityriasis rubra pilaris (PRP) is an idiopathic, papulosquamous inflammatory dermatosis. It is characterized by hyperkeratotic follicular papules coalescing into orange-red scaly plaques, islands of sparing, and palmoplantar keratoderma. PRP can be subdivided into six clinical subtypes according to Griffiths' classification, based on age of onset, disease extent, prognosis, and other associated features. The sixth subtype of PRP occurs in individuals affected by HIV infection, and retroviral screening in all de novo cases of PRP is advised. Other reported associations include various infections, autoimmunity, drugs, and malignancies, although the true significance of these is still unclear. The genetic basis for familial cases, most commonly categorized under the fifth subtype, has been mapped to gain of function mutations in the caspase recruitment domain family, member 14 (CARD14) gene. Treatment of PRP remains a challenge to this day due to a paucity of high-quality evidence. Therapeutic regimens have been guided mostly by case reports and case series, with the mainstay of treatment being oral retinoids. Recently, biologics have emerged as a promising treatment for PRP. We present a review of the clinicopathologic features, pathogenesis, associated disorders, and treatment of PRP, with an emphasis and critical appraisal of the existing literature on the latter.

Biologics for pityriasis rubra pilaris treatment: A review of the literature

Pityriasis rubra pilaris (PRP) is a rare inflammatory papulosquamous skin disease that is often refractory to conventional therapies. The off-label use of biologics, such as anti-tumor necrosis factor, anti-interleukin (IL) 12/IL-23, and anti-IL-17 agents, has been proven successful in the past 2 decades for PRP treatment. Our aim was to analyse the literature for the use of biologics in PRP treatment. We conducted a review by performing PubMed and ClinicalTrials.gov searches. Sixty-eight articles met our selection criteria and are herein discussed. Out of 86 PRP patients, the vast majority were treated with anti-tumor necrosis factor, anti-IL-12/IL-23, or anti-IL-17 biologics, either alone or in combination therapy. A marked-to-complete response was observed in 50%-78%, a partial response in 11%-25%, and no or poor response in 11%-25%. This review has several limitations, including small sample sizes and the lack of shared study design criteria. In some instances, PRP might have resolved spontaneously. Further, the presence of concomitant therapy or the lack of detailed data on previous treatments, makes it difficult to strictly define a therapeutic role per se of specific biologics in PRP. This review shows that biologics may be regarded as a tool for PRP treatment alone or in combination therapy although clinical trials are needed to better assess their efficacy and safety.

CARD14-associated papulosquamous eruption: A spectrum including features of psoriasis and pityriasis rubra pilaris

BACKGROUND

Heterozygous mutations in caspase recruitment domain family member 14 gene (CARD14) have been shown to be associated with psoriasis and familial pityriasis rubra pilaris (PRP). Many subjects with CARD14 mutations display features of both disorders, which can result in diagnostic uncertainty. In addition, these eruptions are often recalcitrant to conventional psoriasis therapies such as methotrexate, oral retinoids, and tumor necrosis factor-α inhibitors.

OBJECTIVE

We sought to describe the clinical characteristics, family history, and response to therapy in subjects with papulosquamous eruptions due to mutations in CARD14.

METHODS

Subjects were referred for genetic testing as part of a registry of subjects with inherited disorders of keratinization. DNA was isolated from blood or saliva, and multiplex targeted sequencing or whole exome sequencing was performed. Clinical histories of subjects with CARD14 mutations were reviewed.

RESULTS

We identified 15 kindreds with CARD14-associated papulosquamous eruption (CAPE). Characteristic features of CAPE include early age of onset; prominent involvement of the cheeks, chin, and ears; family history of psoriasis or PRP; minimal response to conventional topical and systemic psoriasis therapies; and improvement with ustekinumab.

LIMITATIONS

Relatively small sample size.

CONCLUSIONS

Many subjects with CARD14 mutations display characteristics of both psoriasis and PRP. We propose the term CARD14-associated papulosquamous eruption to describe this spectrum of disease. Subjects with clinical features suggestive of CAPE should undergo CARD14 sequencing and may benefit from treatment with ustekinumab.

Desired response to phototherapy vs photoaggravation in psoriasis: what makes the difference?

Psoriasis commonly responds beneficially to UV radiation from natural sunlight or artificial sources. Therapeutic mechanisms include the proapoptotic and immunomodulating effects of UV, affecting many cells and involving a variety of pro- and anti-inflammatory cytokines, downregulating the Th17/IL-23 response with simultaneous induction of regulatory immune cells. However, exposure to UV radiation in a subset of psoriasis patients leads to exacerbation of the disease. We herein shed light on the predisposing factors of photosensitive psoriasis, including genetics (such as HLA-Cw*0602 or CARD14), gender and coexisting photodermatoses such as polymorphic light eruption (PLE) in the context of potential molecular mechanisms behind therapeutic photoresponsiveness or photoaggravation. UV-induced damage/pathogen-associated molecular patterns, damage to self-coding RNA (signalling through Toll-like receptors), certain antimicrobial peptides and/or inflammasome activation may induce innate immunity, leading to psoriasis at the site of UV exposure when there is concomitant, predisposing resistance against UV-induced suppression of the adaptive immune response (like in PLE) that otherwise would act to reduce psoriasis.

Management of refractory pityriasis rubra pilaris: challenges and solutions

Pityriasis rubra pilaris (PRP) is a rare chronic inflammatory papulosquamous skin disease. Its clinical presentation and evolution is very variable. The most frequent clinical features are follicular papules, progressing to yellow-orange erythroderma with round small areas of normal skin and the well-demarcated palmoplantar keratoderma. Actually, six different types of PRP have been described based on clinical characteristics, age of onset, and prognosis. The pathogenesis is still unknown, and treatment can be challenging. Available treatments are mainly based on case reports or case series of clinical experience because no controlled randomized trials have never been performed because of the rarity of the condition. Traditional systemic treatment consists in retinoids, which are actually considered as first-line therapy, but refractory cases that do not respond or relapse after drug interruption do exist. In recent years, numerous reports have demonstrated the efficacy of new agents such as biological drugs. This article is an overview on available therapeutic options, in particular for refractory forms of PRP.

Ustekinumab treatment of pityriasis rubra pilaris: A report of five cases

Pityriasis rubra pilaris (PRP) is a rare, chronic, inflammatory skin disease of unknown etiology. Patients refractory to conventional therapies have been treated successfully with biologic drugs such as anti-tumor necrosis factor agents. Recently, a role of the interleukin-23/T-helper 17 axis in PRP has been described. Our objective was to assess the effectiveness of ustekinumab in five patients with adult-onset PRP refractory to conventional therapies. In the present study, four patients had type I and one patient type II adult-onset PRP. They were treated with three s.c. doses of ustekinumab at weeks 0, 4 and 16. Clinical response was evaluated monthly during treatment up to a 15-month follow-up period. All patients promptly showed a decrease in erythema, follicular hyperkeratosis and scaling. After three injections, complete remission of skin lesions was achieved in four out of five cases and a significant clinical improvement was shown in one case. To the best of our knowledge, this is the largest case series reported on ustekinumab treatment in PRP. Our results, in addition to previous studies from other groups, suggest that ustekinumab may be a possible first-line treatment for PRP patients refractory to conventional therapies.

Epidemiologic, Clinicopathologic, Diagnostic, and Management Challenges of Pityriasis Rubra Pilaris: A Case Series of 100 Patients

IMPORTANCE

Pityriasis rubra pilaris (PRP) is a rare papulosquamous disorder with limited epidemiologic and clinicopathologic data. Little information is available on long-term outcomes, comorbidities, and treatment efficacy.

OBJECTIVE

To evaluate objective and subjective disease experience metrics from the perspectives of patients and clinicians.

DESIGN, SETTING, AND PARTICIPANTS

One hundred patients with a putative diagnosis of PRP and who elected to participate completed a comprehensive survey, followed by acquisition of their medical records, including histopathology slides and reports. The data were analyzed separately from the health care clinician and the patient perspectives. Two academic dermatologists examined clinical notes, pathology reports, and photographs, confirming diagnoses via predetermined criteria. Patients were categorized into 4 levels of diagnostic certainty to allow stratification of the findings for subgroup analysis. Patients with a diagnosis of PRP were solicited through patient support organization websites.

MAIN OUTCOMES AND MEASURES

Clinical outcomes, unexpected association of comorbidities, and efficacy (or lack of it) of various treatment modalities.

RESULTS

Among the 100 patients, 50 were diagnosed as having classic, unquestionable PRP. The patients were a median of 61 years old (range, 5-87 years), and 46% were female. Fifty were categorized as level 1 diagnostic certainty, 15 as level 2, 30 as level 3, and 5 as level 4. Of the level 1 patients, 13 (26%) were correctly diagnosed at initial presentation; diagnosis was delayed, on average, by 29 months (range, 0.25-288 months; median, 2 months); and 27 (54%) having undergone 2 or more biopsies. At enrollment, PRP symptoms had persisted in 36 patients (72%) for an average of 58 months (range, 1-300 months; median, 30 months). Thirty-one patients (62%) had comorbidities, including hypothyroidism (20%). Nearly all patients (98%) received some form of therapy. Patients cited topical emollients, corticosteroids, and salicylic acid along with oral retinoids, methotrexate, and tumor necrosis factor inhibitors as most helpful.

CONCLUSIONS AND RELEVANCE

Pityriasis rubra pilaris remains a challenging diagnosis without established and specific treatment. Our data highlight new potential avenues for research with therapeutic perspective.