Paradoxical eruptions to targeted therapies in dermatology: A systematic review and analysis

Behcet's-like disease induced by secukinumab in a patient with psoriasis: a case report and literature review

Purpose: The incidence of cutaneous paradoxical reactions associated with IL-17 inhibitors has gained attention in recent literature. Our report aims to investigate the characteristics of one rare paradoxical reaction, presenting as Behcet's disease.

Methods: We reported one case of Behcet's-like disease induced by secukinumab in a patient with psoriasis. This patient, a young woman with a long history of psoriasis, showed significant improvement in her psoriatic condition after receiving four doses of secukinumab. Unexpectedly, she developed symptoms such as high fever, painful oral and genital ulcers, facial maculopapules, and erythema nodosum-like lesions on her lower limbs. Despite neutrophilia, there was no evidence of infection found in her laboratory tests. Histological analysis of a skin biopsy highlighted subcutaneous panniculitis and a mixed inflammatory cell infiltrate in the dermis. The patient was consequently diagnosed with secukinumab-induced Behcet's-like disease. Additionally, we have reviewed nine other documented cases of Behcet's-like disease triggered by IL-17 inhibitors.

Results: This group showed no significant gender preference, suffering from conditions such as psoriasis, ankylosing spondylitis, and hidradenitis suppurativa. Oral and genital ulcers were prevalent among the paradoxical reactions noted. Marked improvement was observed in all patients upon discontinuation of the IL-17 inhibitors.

Conclusions: Our report serves to alert physicians to this uncommon but significant paradoxical effect that may arise with anti-IL-17 treatment.

Paradoxical Psoriasis: An Updated Review of Clinical Features, Pathogenesis, and Treatment Options

The definition of paradoxical psoriasis (PP) encompasses 2 main scenarios, namely, (i) new-onset psoriasis in patients treated for a different disease and (ii) worsening as well as phenotypical change of pre-existing psoriasis. Originally restricted to the appearance of an untoward psoriasiform reaction under TNF inhibitors, the term has gained new meaning, with the progressive observation of psoriasis-like eruptions also with other medications. Although the conceptual framework of PP has expanded, a molecular and clinicotherapeutic classification is still lacking. In addition, a certain degree of confusion surrounds the correct terminology to indicate these eruptions. In this paper, evidence on the epidemiology, clinical features, pathogenesis, and treatment of PP is reviewed, providing a perspective on possible pathogenesis-driven therapeutic approaches.

Biologics for Psoriasis

Biologic therapies targeting tumor necrosis factor alpha (TNF-α) (infliximab, adalimumab, certolizumab, etanercept), the p40 subunit shared by IL-12 and IL-23 (ustekinumab), the p19 subunit of IL-23 (guselkumab, tildrakizumab, risankizumab), IL-17A (secukinumab, ixekizumab), IL-17-RA (brodalumab) and both IL-17A and IL-17F (bimekizumab) have revolutionized the treatment of psoriasis. In both the short and long term, risankizumab had highest Psoriasis Area and Severity Index 90 scores compared to other oral and injectable biologics. IL-23 inhibitors had lowest rates of short-term and long-term adverse events and most favorable long-term risk-benefit profile compared to IL-17, IL-12/23, and TNF-α inhibitors.

Study of Genetic Mutations and Their Association With the Development of Atopic Dermatitis and Other Skin Diseases

The purpose of this study was to identify the heterogeneity of atopic dermatitis and to identify key genetic factors. This can lead to new approaches and personalized treatment strategies. I conducted a literature review of three scientific publication platforms (i.e., PubMed, Cochrane Library, Scopus) for records published between July 2011 and July 2023 using key words related to the genetics of atopic dermatitis. The high heritability and genetic pleiotropia of atopic dermatitis emphasize the importance of its genetic predisposition and interaction with concomitant diseases. The study also shows the role of various genes associated with immunity and inflammatory reactions, as well as the high heritability of atopic dermatitis, particularly among twins. Genetic mutations, specifically polymorphisms of genes encoding immune factors and inflammatory responses, determine an individual's predisposition to atopic dermatitis. Research findings also point to genetic aspects associated with other skin conditions such as psoriasis and vitiligo, confirming the existence of common genetic mechanisms between these diseases. Specifically, polymorphisms of the filaggrin gene have been found to be key genetic determinants of atopic dermatitis. I analyzed the genetic basis of atopic dermatitis, emphasizing the importance of genetic determinants and their interaction with the immune system and extracellular matrix. This study contributes to the understanding of the mechanisms of atopic dermatitis and opens new perspectives for individualized treatments.

Paradoxical Psoriasis

Cytokine blocking therapies have revolutionized the management of psoriasis and atopic dermatitis but can lead to the development of paradoxic psoriasis (PP). Patients treated with biologics should be closely monitored for the development of PP and other paradoxical eruptions (including inflammatory joint disease, inflammatory bowel disease, eczematous eruptions, lupus like eruptions, sarcoidal eruptions, and others) and occasionally the development of cutaneous T-cell lymphoma. Further understanding the immunologic mechanism of these processes will ultimately drive our understanding of and ability to predict and manage PPs.

Psoriasis induced by antiTNF therapy in inflammatory bowel disease: Therapeutic management and evolution of both diseases in a nationwide cohort study

BACKGROUND

some patients with inflammatory bowel disease (IBD) treated with antiTNF develop drug-induced psoriasis (antiTNF-IP). Several therapeutic strategies are possible.

AIMS

to assess the management of antiTNF-IP in IBD, and its impact in both diseases.

METHODS

patients with antiTNF-IP from ENEIDA registry were included. Therapeutic strategy was classified as continuing the same antiTNF, stopping antiTNF, switch to another antiTNF or swap to a non-antiTNF biologic. IP severity and IBD activity were assessed at baseline and 16, 32 and 54 weeks.

RESULTS

234 patients were included. At baseline, antiTNF-IP was moderate-severe in 60 % of them, and IBD was in remission in 80 %. Therapeutic strategy was associated to antiTNF-IP severity (p < 0.001). AntiTNF-IP improved at week 54 with all strategies, but continuing with the same antiTNF showed the worst results (p = 0.042). Among patients with IBD in remission, relapse was higher in those who stopped antiTNF (p = 0.025). In multivariate analysis, stopping antiTNF, trunk and palms and soles location were associated with antiTNF-IP remission; female sex and previous surgery in Crohn´s disease with IBD relapse.

CONCLUSION

skin lesions severity and IBD activity seem to determine antiTNF-IP management. Continuing antiTNF in mild antiTNF-IP, and swap to ustekinumab or switch to another antiTNF in moderate-severe cases, are suitable strategies.

Long-term, observational, real-world study of dupilumab for the treatment of moderate-to-severe atopic dermatitis: a 52-week single-center retrospective analysis in China

For dupilumab, real-world long-term follow-up data remain scarce, and studies on optimized treatment modes as well as drug survival rate and its predictors are lacking. To explore the effectiveness of different treatment modes of dupilumab and to understand the drug survival rates of dupilumab in China and its predictive factors. This retrospective study included patients with moderate-to-severe AD who received dupilumab treatment. Their clinical data were collected and analyzed. Compared with baseline, the SCORing Atopic Dermatitis (SCORAD), Eczema Area and Severity Index (EASI), numerical rating scale (NRS), and Atopic Dermatitis Control Tool (ADCT) scores significantly decreased at 12, 24, and 52 weeks (p < 0.0001), and the continuous medication group had more significant improvements in SCORAD, EASI, NRS, and ADCT scores at 52 weeks than the noncontinuous medication group (p < 0.05). The 6-month and 1-year drug survival rates of dupilumab were 59.7% and 51.9%, respectively. The most common reason for treatment discontinuation was the satisfactory control of AD. Patients with adult-onset AD (adjusted odds ratio [OR]: 0.15, 95% confidence interval [CI]: 0.03-0.73) , not complicated by other systemic diseases (adjusted OR: 0.17, 95% CI: 0.04-0.84) and eosinophilia at baseline (adjusted OR: 3.71, 95% CI: 1.12-12.26) had a higher probability of drug discontinuation. In real-world practice in China, dupilumab has exhibited good long-term effectiveness and safety for the treatment of moderate-to-severe AD, and continuous administration can benefit patients in the long term.

Risk Factors for Psoriasis Flares: A Narrative Review

Psoriasis is a chronic inflammatory cutaneous disease with multifactorial pathogenesis involving both genetic and environmental factors as well as the innate and acquired immune response. Several triggering factors may exacerbate or worsen the disease. In this context, we performed a review manuscript with the aim of investigating current literature on psoriasis risk factors, also showing possible mechanisms by which they act on psoriasis. Globally, risk factors can be divided in classic risk factors (eg, mechanical stress, infections and dysbiosis of the skin, common drugs, environment and pollution, lifestyle, psychological stress, hormonal and metabolic alterations) which have long been known to be responsible for worsening and/or reoccurrence of psoriatic manifestations, and emerging risk factors (eg, biological drugs, immunotherapy for oncologic disease, Covid-19, and vaccines) defined as those newly identified risk factors. Accurate patient information and monitoring of risk factors as well as planned follow-ups may help to prevent and treat the worsening of psoriasis and consequently improve the quality of life of psoriatic patients.

Combination of secukinumab and acitretin for generalized pustular psoriasis: A case report and review of literature

Generalized pustular psoriasis (GPP) is characterized by painful and occasionally disfiguring cutaneous manifestations with sepsis-like systemic symptoms, and is a rare severe variant of psoriasis. Currently, there is no standard treatment for GPP. Here, we report a case of a female patient with ankylosing spondylitis (AS) and mild scalp psoriasis, who developed GPP and alopecia following three courses of adalimumab therapy. The patient's condition gradually improved following cessation of adalimumab and treatment with secukinumab and acitretin. After eight weeks of treatment, the patient achieved almost complete clearance of her psoriasis, her alopecia improved, and her AS was relieved. Therefore, we believe that a combination of secukinumab with acitretin may be a rational approach for the treatment of severe GPP.

Targeted Systemic Therapies for Adults with Atopic Dermatitis: Selecting from Biologics and JAK Inhibitors

Therapeutic options for people with moderate or severe atopic dermatitis refractory to topical therapy have rapidly expanded in recent years. These new targeted immunomodulatory agents-biologics and Janus kinase (JAK) inhibitors-have each demonstrated high levels of efficacy and acceptable safety in mostly placebo-controlled clinical trials for atopic dermatitis, but there is no universally applicable algorithm to help choose between them for a given patient. Hence, patients and physicians should utilize shared decision making, discussing efficacy, safety, mode of delivery, monitoring, costs, speed of onset, and other factors to reach individualized treatment decisions. In this review, we try to aid shared decision making by summarizing the efficacy, safety, and monitoring of biologics and oral JAK inhibitors for adults with atopic dermatitis. Network meta-analyses suggest that higher doses of abrocitinib and upadacitinib are more effective than biologics. They also show that, among biologics, dupilumab is likely more effective than tralokinumab and lebrikizumab. Biologics are generally considered safer than JAK inhibitors, although concerns about JAK inhibitors are mainly extrapolated from older generation JAK inhibitors used in higher-risk populations. We also outline evidence and considerations for choosing and using systemic immunomodulatory treatments for special populations including pregnant individuals, those with human immunodeficiency virus (HIV), hepatitis B and C, end stage kidney disease, and older adults.

Safety of Secukinumab from 1 Million Patient-Years of Exposure: Experience from Post-Marketing Setting and Clinical Trials

INTRODUCTION

Secukinumab is an anti-interleukin (IL)-17A monoclonal antibody indicated for multiple immunological disorders. Here, we aim to summarize secukinumab safety in clinical trials (CTs) and post-marketing setting (PMS) until 25 June 2022.

METHODS

Adverse events (AEs) were summarized with crude reporting rate (RR) per 100 patient-years (PY) in PMS for all reported indications and with exposure-adjusted incident rates (EAIR) per 100 PY in pooled 47 CTs for approved indications.

RESULTS

Secukinumab exposure totaled 1,159,260 PY in PMS and 27,765 PY in CTs. AEs were mostly (> 80%) non-serious in PMS. EAIR for serious AEs was 7.0/100 PY. Nasopharyngitis (RR 0.59/100 PY, EAIR 16.08/100 PY) and pneumonia (RR 0.14/100 PY, EAIR 0.17/100 PY) were the most common infection and serious infection, respectively. Candida infections (RR 0.20/100 PY, EAIR 2.16/100 PY) were the most common fungal infections. Inflammatory bowel disease (IBD) was observed in PMS (0.14/100 PY) and CTs (0.26/100 PY). Most (76%) patients with prior IBD did not report IBD flare during CTs. PMS monitoring identified paradoxical skin reactions including dyshidrotic eczema (RR 0.006/100 PY) and pyoderma gangrenosum (RR 0.003/100 PY).

CONCLUSION

Secukinumab safety profile with increased patient exposure remained favorable. Paradoxical skin reactions were identified in post-marketing monitoring.

Cutaneous Sarcoidosis

Sarcoidosis is a multisystem disease that most commonly affects the lungs, lymphatic system, eyes, and skin but any organ may be involved. Cutaneous sarcoidosis most commonly presents as pink-red to red-brown papules and plaques that commonly affect the head and neck. With the skin being readily accessible for evaluation and biopsy, when sarcoidosis is suspected, dermatologic evaluation may be helpful for establishing a definitive diagnosis. Treatment strategy depends on the severity and distribution of skin lesions and should incorporate patient preference and treatment considerations for other organs that may be involved.

Adalimumab-Induced Erythrodermic Psoriasis Associated with Alopecia in a Patient with Palmoplantar Pustulosis

In recent years, with the increased usage of tumour necrosis factor (TNF) inhibitors, more side effects have been revealed. Paradoxical psoriasis, including psoriasis vulgaris, palmoplantar pustulosis, scalp psoriasis and their combinations, is a common adverse effect. However, erythrodermic psoriasis associated with alopecia due to anti-TNF-α is rarely reported in the literature. We report a 44-year-old woman who developed erythrodermic psoriasis associated with diffuse alopecia during her treatment with adalimumab for palmoplantar pustulosis.

Application of JAK inhibitors in paradoxical reaction through immune-related dermatoses

Biologics play a positive and effective role in the treatment of immune-related dermatoses. However, many other immune-related diseases have also manifested along with biologics treatment. Paradoxical reaction through immune-related dermatoses refer to the new onset or exacerbation of other immune-mediated dermatoses (mainly psoriasis and atopic dermatitis) after biologics treatment of inflammatory dermatoses (mainly psoriasis and atopic dermatitis), such as new atopic dermatitis (AD) in psoriasis (PsO) treatment and new PsO in AD treatment. A common genetic background and Inflammatory pathway are possible pathogenesis. Faced with paradoxical reactions, the choice of therapy needs to be directed toward therapies effective for both diseases, such as Janus kinase (JAK) inhibitors. The Janus kinase and signal transducer and activator of transcription (JAK-STAT) pathway plays an important role in the inflammatory pathway, and has been widely used in the treatment of AD and PsO in recent years. This article focuses on JAK inhibitors such as tofacitinib, baricitinib, ruxolitinib, Abrocitinib, upadacitinib, and deucravacitinib, to explore the possible application in treatment of paradoxical reactions. Common side effects, baseline risk factors and safety use of JAK inhibitors were discussed.

Paradoxical Psoriasis Induced by Ustekinumab: A Comprehensive Review and Case Report

Ustekinumab (UST), a biologic agent targeting interleukin-12 and interleukin-23, is widely used in the management of psoriasis and Crohn's disease. Despite its efficacy, there have been instances of paradoxical psoriasis induction or exacerbation in some patients during UST therapy. This paper offers a comprehensive review of reported cases of UST-induced paradoxical psoriasis, including a case from our clinic. We focus on a 39-year-old female patient with a history of long-standing Crohn's disease who developed a psoriasiform rash, as confirmed by biopsy, while undergoing UST treatment. The patient's clinical journey, from initial diagnosis through the complexities of treatment adjustments due to various complications including drug-induced lupus and the subsequent onset of psoriatic manifestations, provides insight into the challenges encountered in the clinical management of such cases. This review emphasizes the necessity for clinicians to recognize the possibility of paradoxical psoriasis in patients receiving UST treatment and calls for further research to better understand this phenomenon and devise effective management strategies.

Pyoderma gangrenosum after surgery for forefoot deformity in a patient with rheumatoid arthritis: A case report

Pyoderma gangrenosum (PG) is a rare inflammatory skin disease characterised by skin ulcers that are associated with autoimmune diseases. Although the effectiveness of immunosuppression with glucocorticoids and tumour necrosis factor inhibitors in treating PG has been reported, the utility of negative-pressure wound therapy (NPWT) for severe ulcerative lesions in patients with PG remains controversial. Herein, we report the case of a 76-year-old woman with rheumatoid arthritis who developed PG after undergoing surgery for a forefoot deformity. The patient showed improvement in deep ulcer lesions through NPWT while receiving treatment with abatacept and systemic glucocorticoids. Subsequent topical glucocorticoid therapy led to the remission of the PG. This case suggests that NPWT, when used under immunosuppressive conditions, does not exacerbate the pathergy and may be beneficial for treating severe ulcerative PG.

Predictive factors of atopic-like dermatitis induced by IL-17A inhibitors in patients with psoriasis: A 2-year follow-up study

BACKGROUND

Atopic-like dermatitis (ALD) is a common side effect of interleukin-17A (IL-17A) inhibitors.

OBJECTIVE

To determine the prevalence, risk factors, outcomes and treatment of ALD in a cohort of psoriasis patients treated with IL-17A inhibitors.

METHODS

This retrospective study included 226 psoriasis patients treated with an IL-17A inhibitor in our dermatology department between July 2020 and July 2022. The patients were reviewed over 2 years. A logistic regression model in rare events data (relogit) was used to predict the risk factors for ALD.

RESULTS

Of the 226 patients, 14 had ALD. Data including age, body mass index, IL-17A inhibitor use, personal and family history of atopic disease, pet ownership history, and immunoglobulin E (IgE) levels were analysed using the relogit regression model. It indicated a personal history of atopic disease (odd ratio [OR] 27.830, 95% confidence interval [CI] 3.801-203.770; p = 0.001) and elevated IgE levels (OR 5.867, 95% CI 1.131-30.434; p = 0.035) as independent predictors of incident ALD. In one patient, anti-IL-17A therapy was discontinued, and treatment was switched to tofacitinib. Thirteen patients who continued with IL-17A inhibitor were treated with topical therapy and/or antihistamines, and their ALD was partially or completely resolved.

CONCLUSION

In this study, the incidence rate of ALD was 6.19%. Elevated IgE levels and a personal history of atopic disease were found to be the risk factors for ALD. Our study findings suggest that treatment should be provided based on the severity of psoriasis and incident ALD. Prior to treatment, psoriasis patients who have the risk factors for ALD should be informed of the possible development of ALD, and alternative psoriatic therapeutic options should be considered if severe ALD develops.

Eosinophils-from cradle to grave: An EAACI task force paper on new molecular insights and clinical functions of eosinophils and the clinical effects of targeted eosinophil depletion

Over the past years, eosinophils have become a focus of scientific interest, especially in the context of their recently uncovered functions (e.g. antiviral, anti-inflammatory, regulatory). These versatile cells display both beneficial and detrimental activities under various physiological and pathological conditions. Eosinophils are involved in the pathogenesis of many diseases which can be classified into primary (clonal) and secondary (reactive) disorders and idiopathic (hyper)eosinophilic syndromes. Depending on the biological specimen, the eosinophil count in different body compartments may serve as a biomarker reflecting the underlying pathophysiology and/or activity of distinct diseases and as a therapy-driving (predictive) and monitoring tool. Personalized selection of an appropriate therapeutic strategy directly or indirectly targeting the increased number and/or activity of eosinophils should be based on the understanding of eosinophil homeostasis including their interactions with other immune and non-immune cells within different body compartments. Hence, restoring as well as maintaining homeostasis within an individual's eosinophil pool is a goal of both specific and non-specific eosinophil-targeting therapies. Despite the overall favourable safety profile of the currently available anti-eosinophil biologics, the effect of eosinophil depletion should be monitored from the perspective of possible unwanted consequences.

Paradoxical inflammatory blepharitis in a patient with Crohn's disease

We report the case of a 15-year-old boy with severe inflammatory blepharitis who was being treated with a TNFα inhibitor for Crohn's disease (CD). This case shows the potential utility of a skin biopsy in distinguishing metastatic CD associated with granulomatous blepharitis from a paradoxical blepharitis induced by anti-TNFα. It also demonstrates that ustekinumab can be considered in patients with CD who cannot tolerate TNFα inhibitors because of cutaneous paradoxical reactions.

Paradoxical psoriasis: The flip side of idiopathic psoriasis or an autocephalous reversible drug reaction?

Psoriasis is a common, chronic skin disease that results mainly from the complex interplay between T cells, dendritic cells, and inflammatory cytokines including TNF-α, IL-17, IL-12, and IL-23. Successful therapy with anti-cytokine antibodies has proved the importance of these key cytokines, especially TNF-α. During the anti-TNF-α treatment of classical idiopathic psoriasis, a small portion of patients develop new psoriasiform lesions. This contradictory phenomenon was named paradoxical psoriasis which resembles idiopathic psoriasis clinically but presents overlapped histological patterns and distinct immunological processes. In this review, we discuss the differences between idiopathic psoriasis and paradoxical psoriasis with an emphasis on their innate immunity, as it is predominant in paradoxical psoriasis which exhibits type I IFN-mediated immunity without the activation of autoreactive T cells and memory T cells. We also put up an instructive algorithm for the management of paradoxical psoriasis. The decision on drug discontinuation or switching of biologics should be made based on the condition of underlying diseases and the severity of lesions.

The predictors of paradoxical reactions, especially psoriasis, to biologic therapy-findings from the TReasure database: a 5-year follow-up study

OBJECTIVES

The objectives of this study were to assess the clinical characteristics, predictive factors, and practical algorithms of paradoxical reactions (PRs), specifically paradoxical psoriasis (PP).

METHODS

The TReasure database is a web-based prospective observational cohort comprised of patients with RA and SpA from 17 centres around Turkey since 2017. A cohort study and a case-control study nestled within the cohort were identified.

RESULTS

In total, 2867 RA and 5316 SpA patients were evaluated. The first biologic agent was found to have caused PRs in 60% of the 136 patients (1.66%) who developed the PRs. The median time interval between the PRs and biological onset was 12 months (range 1-132 months, mean 21 months). The most common types of PP, constituting 92.6% of PRs, were pustular (60.3%) and palmoplantar (30.9%). Adalimumab (30.9%), infliximab (19%) and etanercept (17.4%) were the most common agents causing the PP. In the treatment of most PP patients (73.2%), switching biologic agents was favoured, with TNF inhibitor (TNFi) chosen in 46.03% and non-TNFi in 26.9% of cases. The three most frequently selected drugs were etanercept (24.6%), secukinumab (9.5%) and adalimumab (8.7%). Only 5.17% of patients who switched to another TNFi showed progression. The odds ratios (s) for SSZ, HCQ, and LEF use were significantly higher in RA controls than in PP patients (P = 0.033, OR = 0.15; P = 0.012, OR = 0.15; and P = 0.015, OR = 0.13, respectively). In the PP group with SpA, the number of smokers was significantly higher (P = 0.003, OR: 2.0, 95% CI: 1.05, 3.81).

CONCLUSION

Contrary to expectations based on earlier research suggesting that paradoxical reactions develop with the class effect of biological agents, the response of patients who were shifted to another TNFi was favourable.

Paradoxical Psoriasis and Worsening Spondylitis Due to Secukinumab in a Patient With Ankylosing Spondylitis: A Case Report and Literature Review

Axial spondyloarthritis (axSpA) is an autoimmune disease primarily affecting the axial skeleton, with associated extra-musculoskeletal manifestations. Treatment strategies targeting cytokines tumor necrosis factor-alpha (TNF-α) and interleukin 17 (IL-17) have proven effective. However, paradoxical reactions, including paradoxical psoriasis and arthritis, have been reported in axSpA patients receiving TNF-α inhibitors. IL-17 inhibitors have been used as an alternative treatment option, but paradoxical reactions have also been rarely observed. This case report presents a 45-year-old man with axSpA who responded to infliximab for six years before discontinuing it due to secondary failure. After the washout period of infliximab, he was started on secukinumab but developed paradoxical psoriasis and worsening of inflammatory back pain after receiving the second loading dose which necessitated replacing it with upadacitinib. Complete resolution of paradoxical psoriasis and significant improvement in his back pain after three months ensued. This case contributes to understanding the complex dynamics in treating axSpA and managing paradoxical reactions.

Secukinumab-Induced Alopecia Areata Successfully Treated with Tofacitinib in a Patient with Palmoplantar Pustulosis

Secukinumab, a monoclonal antibody targeting interleukin-17 (IL-17), has exhibited encouraging results in the therapeutic management of palmoplantar pustulosis (PPP). The development of alopecia areata (AA) is closely related to IL-17, and IL-17A inhibitors were considered as a potential treatment modality. Therefore, the development of AA during secukinumab treatment for PPP is a rare adverse event that has been rarely reported worldwide. Here we report a 35-year-old female patient with PPP who developed AA after completing the induction period of secukinumab treatment. Discontinuing secukinumab and initiating treatment with tofacitinib resulted in a significant improvement in both PPP and AA. The emergence of AA in this patient can be attributed to paradoxical skin reactions associated with IL-17 inhibitors. Tofacitinib appears to alleviate biologic-induced AA during PPP syndrome treatment.

Pyoderma Gangrenosum: Treatment Options

Pyoderma gangrenosum is a rare neutrophilic dermatosis that leads to exceedingly painful ulcerations of the skin. Although the exact pathogenesis is not yet fully understood, various auto-inflammatory phenomena with increased neutrophil granulocyte activity have been demonstrated. Despite the limited understanding of the pathogenesis, it is no longer a diagnosis of exclusion, as it can now be made on the basis of validated scoring systems. However, therapy remains a major multidisciplinary challenge. Various immunosuppressive and immunomodulatory therapies are available for the treatment of affected patients. In addition, concomitant topical pharmacologic therapy, wound management and pain control should always be addressed. Corticosteroids and/or cyclosporine remain the systemic therapeutics of choice for most patients. However, in recent years, there has been an increasing number of studies on the positive effects of biologic therapies such as inhibitors of tumour necrosis factor-α; interleukin-1, interleukin-17, interleukin-23 or complement factor C5a. Biologics have now become the drug of choice in certain scenarios, particularly in patients with underlying inflammatory comorbidities, and are increasingly used at an early stage in the disease rather than in therapy refractory patients.

Biologic Versus Small Molecule Therapy for Treating Moderate to Severe Atopic Dermatitis: Clinical Considerations

The U.S. Food and Drug Administration approval of dupilumab for moderate-to-severe atopic dermatitis shifted the paradigm from use of broad, systemic immunosuppressants to a safer, targeted treatment and led to the emergence of newer interleukin (IL)-4/IL-13 directed biologics and small molecule therapies, namely Janus kinase (JAK) inhibitors (JAKi). Tralokinumab and emerging (not yet approved) lebrikizumab, which both target IL-13, are alternative biologics to dupilumab. The emerging anti-IL-31 receptor nemolizumab is likely to be used second-line to other biologics, primarily for pruritus. Three JAKi are currently in use for treating atopic dermatitis, 2 of which, abrocitinib and upadacitinib, are U.S. Food and Drug Administration-approved. This review provides an in-depth, practical discussion on use of these biologics and JAKi that are approved or have completed phase 3 clinical trials in pediatric patients and adults, comparing the groups of medications based on available efficacy and safety data.

Tumor necrosis factor-α inhibitor-related immune disorders

Biotechnological monoclonal antibodies and receptor antagonists capable of targeting specific inflammatory actors, such as cytokines, cytokines receptors, co-stimulatory molecules or leukocyte populations, have emerged as an alternative to conventional therapies for treating systemic inflammatory diseases with immune pathogenesis. However, there is no doubt that, with a frequency that is not exceptionally high but also not negligible, immunotherapies can favour the development of systemic and organ-specific immune-mediated disorders. It has become increasingly evident that interference with a specific immune pathway may favour the activation of opposing compensatory signalling, which may exacerbate underlying subclinical disorders or cause immune-mediated diseases completely different from the underlying disease. The 'compensatory immunological switch' has emerged primarily in patients treated with tumor necrosis factor (TNF) -α inhibitors, the first biological drugs approved for treating systemic inflammatory diseases with immune pathogenesis. In this Review, we describe the clinical features and predisposing factors of the main TNF-α inhibitor-related immune disorders, organising them into subclinical serological autoimmunity, autoimmune disorders other than those for which TNF-α inhibitors are indicated, and paradoxical reactions. We also discuss the underlying pathogenetic mechanisms and precautions for use in the therapeutic management of these patients. Better understanding of the complex phenomenon of the 'compensatory immunological switch', which TNF-α inhibitors and other biological drugs might trigger, can help not only appropriately managing immune-mediated disorders, but also better interpreting the heterogeneity of the pathogenetic mechanisms underlying certain chronic inflammatory conditions that, although different from each other, are arbitrarily placed in the context of overly generic nosological entities.

Inducible nitric oxide synthase-expressing myeloid-derived suppressor cells regulated by interleukin 35 contribute to the pathogenesis of psoriasis

Although psoriasis is classified as a T cell-mediated inflammatory disease, the contribution of myeloid cells to the pathogenesis of psoriasis is not fully understood. In the present study, we demonstrated that the expression of the anti-inflammatory cytokine interleukin-35 (IL-35) was significantly increased in patients with psoriasis with a marked increase in the number of myeloid-derived suppressor cells (MDSCs). Similar results were obtained in an imiquimod-induced psoriasis mouse model. IL-35 reduced the total number of MDSCs and their subtypes in the spleens and psoriatic skin lesions, ameliorating psoriasis. IL-35 also reduced the expression of inducible nitric oxide synthase in MDSCs, although it had no significant effect on interleukin-10 expression. Adoptive transfer of MDSCs from imiquimod-challenged mice aggravated the disease and weakened the effect of IL-35 in the recipient mice. In addition, mice transferred with MDSCs isolated from inducible nitric oxide synthase knockout mice had milder disease than those with wild-type MDSCs. Furthermore, wild-type MDSCs reversed the effects of IL-35, while MDSCs isolated from inducible nitric oxide synthase knockout mice did not affect IL-35 treatment. In summary, IL-35 may play a critical role in the regulation of iNOS-expressing MDSCs in the pathogenesis of psoriasis, highlighting IL-35 as a novel therapeutic strategy for patients with chronic psoriasis or other cutaneous inflammatory diseases.

Tumor necrosis factor-α inhibitor-induced morphea and psoriasiform dermatitis in a pediatric patient with Crohn's disease

Tumor necrosis factor-alpha inhibitor therapy for inflammatory bowel disease may be associated with paradoxical cutaneous adverse events, most commonly psoriasiform eruptions. We present the case of a pediatric female patient with Crohn's disease who developed multiple concurrent cutaneous eruptions while on infliximab treatment, including morphea, psoriasiform dermatitis, and genital lichen sclerosus. Although refractory to skin-directed treatments, all three conditions resolved upon discontinuation of infliximab, supporting their development as a paradoxical reaction to infliximab therapy.

Cutaneous T-cell lymphoma following dupilumab use: a systematic review

In recent years, studies have associated dupilumab with unmasking or progression of cutaneous T-cell lymphoma (CTCL). The objective of this study was to synthesize reported cases of CTCL in the setting of dupilumab use. Two independent reviewers conducted a systematic review using PubMed and Embase databases. Twelve studies, of 27 total patients, were included. Dupilumab-associated CTCL was diagnosed on average 7.8 months following dupilumab initiation. Of reports that included body surface area (BSA), 100% had a BSA >50% prior to diagnosis, and the majority of patients were diagnosed at later stages of disease: stage III (4/18) or IV (6/18). Post-dupilumab biopsies revealed a greater density of cells and a predominant lichenoid pattern, compared to various histologic patterns and less cell density in pre-dupilumab biopsies. The majority of TCR gene rearrangement studies were equivocal (20%) or negative (60%), posing a potential diagnostic pitfall. Limitations included lack of standardized data collection and reporting and a small number of studies. We suggest that earlier biopsies, three to four months after initiation of dupilumab, may be helpful for earlier recognition of CTCL in patients who are not improving, progressing, or have morphologic changes on dupilumab.

Paradoxical reactions and biologic agents: a French cohort study of 9,303 patients

BACKGROUND

Paradoxical reactions (PRs) are defined as the occurrence during biologic therapy of a pathological condition that usually responds to these drugs.

OBJECTIVE

To estimate the incidence of PRs and identify risk factors.

METHODS

Multicenter study of the database for the Greater Paris University Hospitals including biological-naïve patients receiving anti-tumor necrosis factor-α, anti-interleukin-12/23, anti-interleukin-17 or anti-α4ß7-integrin agents for psoriasis, inflammatory rheumatism or inflammatory bowel disease (IBD). We used natural language processing algorithms to extract data. A cohort and a case-control study nested in the cohort with controls selected by incidence density sampling was used to identify risk factors.

RESULTS

Most of the 9,303 included patients (median age 43.0; 53.8% women) presented an IBD (3,773 [40.6%]) or a chronic inflammatory rheumatic disease (3,708 [39.9%]), and 8,487 (91.2%) received anti-TNF-α agents. A total of 293 (3.1%) had a PR. The global incidence rate was 7.6 per 1,000 person-years (95%CI 6.7-8.4). Likelihood of PR was associated with IBD (adjusted OR [aOR] 1.9, 95%CI 1.1-3.2, p=0.021) and a combination of two inflammatory diseases (aOR 6.1, 95%CI 3.6-10.6, p<0.001) and was reduced with conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs) and corticosteroids (aOR 0.6, 95%CI 0.4-0.8, p=0.003; 0.4, 0.2-0.7, p<0.001).

CONCLUSION

Likelihood of PRs was associated with IBD or a combination of a least two inflammatory diseases. More studies are needed to assess the benefit of systematically adding csDMARDs for such high-risk patients.

[Acute sarcoid myopathy and neuropathy aggravated by ustekinumab administration in an elderly woman with psoriasis and systemic sarcoidosis]

A 72-year old woman, who had a history of psoriasis and psoriatic arthritis from age of 69, was admitted because of acute progression of dyspnea and generalized muscle weakness after initiation of ustekinumab. She had been diagnosed as having lung and eye sarcoidosis ten months before admission. Nerve conduction studies revealed multiple mononeuropathy and needle electromyography showed myogenic changes with spontaneous activities. Muscle pathology showed non-caseating epithelioid granuloma and high expression of HLA-class I in myofibers. Diagnosis of sarcoid myopathy and neuropathy aggravated by ustekinumab was made, and ustekinumab administration was discontinued, resulting in slight improvement of her respiratory and neuro-muscular symptoms, but her symptoms remained severely disabled. Treatment with oral steroids further improved her clinical symptoms and she became able to walk independently. We considered that ustekinumab inhibited IL-12 and IL-23 signaling, which caused an imbalance in Th1/Th17 differentiation and activation of Th1 cell differentiation, thereby promoting the development of sarcoid myopathy and neuropathy.

Pathogenesis of Paradoxical Reactions Associated with Targeted Biologic Agents for Inflammatory Skin Diseases

Targeted biologic agents have dramatically changed the therapeutic landscape for immune-mediated inflammatory diseases, particularly in rheumatology and dermatology. Their introduction has resulted in a paradigm shift, i.e., they produce significant clinical improvements in most patients with such diseases. Nevertheless, a variety of adverse reactions associated with these agents have been observed, including so-called paradoxical reactions (PRs), which are a new class of adverse events. PRs involve the de novo development or worsening of immune-mediated inflammatory disease during treatment with a targeted biologic agent that is commonly used to treat the idiopathic counterpart of the drug-induced reaction. In addition, the efficacy of biologic agents targeting individual cytokines and the existence of PRs to them have provided proof that cytokines are key drivers of various immune-mediated inflammatory diseases and helped researchers elucidate the molecular pathways underlying the pathophysiology of these diseases. Here, a comprehensive review of the targeted biologic agents used to treat immune-mediated inflammatory diseases, particularly psoriasis and atopic dermatitis, is provided, with a specific focus on biologic agents that inhibit cytokine signaling involving tumor necrosis factor-α, interleukin (IL)-12/23 (p40), IL-17A (and the IL-17 receptor [R]), IL-23 (p19), and the IL-4Rα, and their associated PRs. The characteristic clinical manifestations and potential immunological mechanisms of the PRs induced by these biologic agents are also reviewed.

Inhibition of type 1 immunity with tofacitinib is associated with marked improvement in longstanding sarcoidosis

Sarcoidosis is an idiopathic inflammatory disorder that is commonly treated with glucocorticoids. An imprecise understanding of the immunologic changes underlying sarcoidosis has limited therapeutic progress. Here in this open-label trial (NCT03910543), 10 patients with cutaneous sarcoidosis are treated with tofacitinib, a Janus kinase inhibitor. The primary outcome is the change in the cutaneous sarcoidosis activity and morphology instrument (CSAMI) activity score after 6 months of treatment. Secondary outcomes included change in internal organ involvement, molecular parameters, and safety. All patients experience improvement in their skin with 6 patients showing a complete response. Improvement in internal organ involvement is also observed. CD4⁺ T cell-derived IFN-γ is identified as a central cytokine mediator of macrophage activation in sarcoidosis. Additional type 1 cytokines produced by distinct cell types, including IL-6, IL-12, IL-15 and GM-CSF, also associate with pathogenesis. Suppression of the activity of these cytokines, especially IFN-γ, correlates with clinical improvement. Our results thus show that tofacitinib treatment is associated with improved sarcoidosis symptoms, and predominantly acts by inhibiting type 1 immunity.

Review article: paradoxical psoriasis as a consequence of tumour necrosis factor antagonists in patients with inflammatory bowel disease

BACKGROUND

Tumour necrosis factor (TNF) antagonists are an efficacious therapy used in the management of several immune-mediated inflammatory diseases, including inflammatory bowel disease (IBD) and psoriasis. However, since being prescribed more widely, reports of new-onset psoriatic lesions have began to emerge in the literature and are known as paradoxical psoriasis.

AIM

To review the evidence available in both the dermatology and gastroenterology literature pertaining to the entity known as paradoxical psoriasis as it relates to IBD and to create a comprehensive guide to assist clinicians who treat this challenging patient population.

METHODS

A literature search was conducted in PubMed to identify manuscripts that presented, discussed or summarised data pertaining to paradoxical psoriasis presenting in individuals with IBD.

RESULTS

Paradoxical psoriasis is now thought to be a contradictory effect of TNF antagonist therapy leading to psoriatic lesions often within the first year of treatment. The underlying pathogenesis, although not completely understood, is likely related to an imbalance of inflammatory cytokines. The histological appearance, while similar to classical psoriasis, does have unique features. The clinical presentation can vary among patients but often presents during maintenance therapy for inflammatory bowel disease. Treatment options should be determined based upon the severity of the skin lesion, activity of the underlying inflammatory bowel disease and the patient's unique clinical history.

CONCLUSIONS

The approach to paradoxical psoriasis in IBD should be discussed with a multidisciplinary team to optimise and preserve intestinal disease remission and to ensure the resolution of debilitating skin lesions.

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

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

Eczematous drug eruption in patients with psoriasis under anti-interleukin-17A: does interleukin-22 play a key role?

BACKGROUND

Eczematous drug eruption (EDE) is a spongiotic skin reaction in response to systemic medications. To date, EDE has been described in patients treated with anti-interleukin (IL)-17A monoclonal antibodies with a prevalence of 2.2%-12.1%.

AIM

To describe the clinical and histological features and the skin cytokine milieu in patients with EDE induced by anti-IL-17A biologics.

METHODS

This was a prospective study, enrolling patients with psoriasis who developed EDE during treatment with two anti-IL-17 biologics, ixekizumab and secukinumab, from June 2019 to April 2021. Skin biopsies were taken from all patients: a 5-mm lesional biopsy (LB) and a 3-mm nonlesional biopsy (NLB). The LB sample was split into two parts, one for histological examination and the other for cytokine profile evaluation.

RESULTS

During the study period, treatment with an anti-IL-17A drug was given to 289 patients of whom 8 (2.8%) developed EDE during the treatment. Histopathological evaluation suggested a diagnosis of spongiotic dermatitis in all eight patients. Cytokine gene expression showed a predominance of T helper (Th)2/Th22 cytokines in EDE lesions with a large increase in IL-4, IL-22 and S100A7 levels in both LB and NLB samples compared with healthy skin. IL-4, IL-22 and S100A7 were significantly higher in LB compared with NLB samples. IL-26 levels were also significantly increased in both LB and NLB compared with healthy skin, whereas low levels of IL-23A were found in both LB and NLB.

CONCLUSION

Eczematous drug eruption skin lesions have mainly Th2/Th22 features, with IL-22 playing a major role in their pathogenesis. EDE seems to be the result of an imbalance towards a Th2/Th22 response, secondary to the blockade of IL-17A activity.

Management of inadequate response and adverse effects to dupilumab in atopic dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by pruritus, skin pain, and sleep disturbances. Currently, dupilumab is the only systemic therapy and biologic medication approved by the United States Food and Drug Administration for moderate-to-severe AD in adults and children. There is a sparsity of literature available on determining treatment failure with dupilumab and the next steps health care providers can take to treat AD. Individual goals and quality of life and not just body surface area should be considered when defining treatment failure. Possible confounding dermatoses also should be ruled out. Early identification of dupilumab-induced adverse events is important. For most patients, dupilumab can be continued while treatment for the adverse event is initiated. Adjusting the frequency of dupilumab dosing also may be considered in some circumstances. Adjuvant therapies, such as methotrexate, azathioprine, mycophenolate mofetil, cyclosporine, or phototherapy can be added but the safety and efficacy of these combination treatments are not known at this time.