Hidradenitis suppurativa (HS): An unrecognized paradoxical effect of biologic agents (BA) used in chronic inflammatory diseases

Paradoxical and bimodal immune-mediated dermatological side effects of TNF-α inhibitors: A comprehensive review

INTRODUCTION

Due to the increasing prevalence of immune-mediated diseases such as psoriasis, lichen planus, rheumatoid arthritis and inflammatory bowel disease, dermatologists have turned to new biologic drugs known as DMARDs (disease-modifying anti-rheumatic drugs) in recent years.

AREAS COVERED

In this study, we evaluate the immune-mediated dermatological side effects of DMARDS by reviewing and analyzing previous peer-reviewed research on the effects of TNF-α inhibitors in the treatment of skin diseases, as well as adverse effects of these drugs and some of the main causes of these effects.

EXPERT OPINION

DMARDs are very effective in improving control of the above diseases. TNF-α inhibitors are an important group of DMARDs that are widely used. The paradoxical adverse events (PAEs) associated with the use of TNF-α inhibitors are divided into three categories: true paradoxical, borderline paradoxical, and non-paradoxical. True PAEs include conditions for which TNF-α inhibitors are approved for treatment. Borderline PAEs are considered to occur with this class of drugs for which there is no definite approval but for which there is sufficient evidence. Although these events are rare, early recognition of the accused drug and appropriate decision-making may prevent progression of complications and irreversible side effects.

Late-Onset Hydroxyurea-Induced Melanonychia and Tongue Hyperpigmentation in a Patient With Polycythemia Vera: A Case Report

In a rare case, a 70-year-old female with polycythemia vera developed late-onset melanonychia, a seldom-documented side effect of hydroxyurea. Typically, melanonychia emerges within months of treatment, but this case is unique as it occurred four years into therapy. Notably, the patient, with darker skin, also had hyperpigmentation of her hands and tongue. Her history of hydroxyurea-associated ulcers and symptoms worsening with dose adjustment suggested drug involvement. While mucocutaneous hyperpigmentation from hydroxyurea is known, melanonychia and tongue hyperpigmentation are rarely reported, mostly in early treatment. This case highlights the importance of recognizing these side effects, especially in diverse populations and darker skin tones. The diverse skin tones seen in Sub-Saharan Africa add complexity to diagnosing such dermatological conditions, highlighting the need for awareness. Melanonychia can mimic severe conditions such as subungual melanoma, emphasizing the significance of accurate recognition and management without invasive tests. Educating clinicians and patients about these benign drug-related phenomena is essential for precise identification and management. This case contributes to understanding late-onset hydroxyurea-induced melanonychia and tongue hyperpigmentation, enhancing clinical knowledge in diverse populations.

Efficacy of medical treatments for pediatric hidradenitis suppurativa: A systematic review

Hidradenitis suppurativa (HS) is a chronic, inflammatory skin condition that has been insufficiently studied in the pediatric population. Timely and effective medical treatments may improve quality of life, mitigate disease burden, and prevent the need for invasive procedural interventions such as surgical excisions. However, there is a paucity of research on the efficacy of medical management strategies for HS in children and adolescents. The aim of this study was to perform a systematic review of the literature on the efficacy and safety of medical treatments for HS in patients <18 years of age. In April 2022, MEDLINE and EMBASE databases were searched for articles on the efficacy of medical treatments for HS in the pediatric population. Between 1984 and 2022, 35 articles (101 patients) met the inclusion criteria. Most patients had Hurley Stage II disease (46.7%, 35/75) followed by Stage I (36%, 27/75), and Stage III (17.3%, 13/75). 100% (23/23) of patients responded to antibiotics, 100% (8/8) to finasteride, 93.9% (31/33) to biologics, 80% (4/5) to oral retinoids, and 50% (6/12) to metformin. Overall, this study demonstrates that medical treatment regimens can improve HS symptoms in pediatric patients, but the extent of improvement is unclear, and the results were largely based on case reports or case series. Prospective studies are warranted to better understand the efficacy and safety of medical treatments for pediatric HS. Clinical trials of HS therapies need to be inclusive of pediatric patients to help define the optimal timing of treatment initiation and guide patient selection.

Hidradenitis suppurativa and psoriasis: the odd couple

Psoriasis and hidradenitis suppurativa are chronic inflammatory skin diseases that can develop together, negatively impacting on the patient's quality of life. We aimed to review the most up-to-date information regarding the epidemiology, pathogenesis, clinical presentation and possible therapeutical choices in patients with both psoriasis and hidradenitis suppurativa, thus linking these two autoimmune and autoinflammatory conditions. A narrative review of articles dating from 2017 to 2022 has been performed using the PubMed database. We analyzed the case reports and case series found in the literature regarding patients who suffered from both psoriasis and HS. Psoriasis arose before hidradenitis suppurativa in the majority of cases, while only a minority of them had hidradenitis suppurativa before psoriasis. Interestingly, some patients suffered from paradoxical hidradenitis suppurativa following biological therapy administered to treat the already present psoriasis. Lastly, new biological drugs have been marketed with great success for the outcome of psoriasis, but similar progress did not happen for hidradenitis. Novel therapeutic approaches and lines of research are needed for the treatment of these pathologies, even if concomitant, in order to improve patient's quality of life.

Commonly prescribed medications associated with alopecia

BACKGROUND

The diagnosis and treatment of medication-associated alopecia often challenges patients and physicians. While numerous studies on the topic exist, limited information on the strength and magnitude of these studies exists.

OBJECTIVES

We investigated the most commonly prescribed medications with high levels of evidence to support associations with alopecia.

METHODS

A list of most commonly prescribed medications was compiled using the "Top 100 Prescriptions, Sales" (Intercontinental Marketing Services) and "Top 200 Names Searched" (RxList.com). PubMed, Embase, and Web of Science were searched for "generic drug name" AND "alopecia" and "generic drug name" AND "hair loss." Two reviewers independently reviewed articles for drug, study type and level of evidence, and number of alopecia cases.

RESULTS

A total of 192 unique drugs were investigated, with 110 yielding positive search results. Of these, 13 were associated with alopecia in studies with strong levels of evidence (adalimumab, infliximab, budesonide, interferon β-1α, tacrolimus, enoxaparin, zoster vaccine, lamotrigine, docetaxel, capecitabine, erlotinib, imatinib, and bortezomib).

LIMITATIONS

Only full-length articles available in the English language were included. The methodology used relied on lists of drugs based on their sales rather than number of prescriptions, which likely overrepresented expensive drugs.

CONCLUSIONS

Few studies with high levels of evidence have been conducted on the topic of medication-associated alopecia. The mechanisms of hair loss must be further identified to provide effective management.

Transcriptome Meta-Analysis Confirms the Hidradenitis Suppurativa Pathogenic Triad: Upregulated Inflammation, Altered Epithelial Organization, and Dysregulated Metabolic Signaling

Hidradenitis suppurativa (HS) is an inflammatory skin condition clinically characterized by recurrent painful deep-seated nodules, abscesses, and sinus tracks in areas bearing apocrine glands, such as axillae, breasts, groins, and buttocks. Despite many recent advances, the pathophysiological landscape of HS still demands further clarification. To elucidate HS pathogenesis, we performed a meta-analysis, set analysis, and a variant calling on selected RNA-Sequencing (RNA-Seq) studies on HS skin. Our findings corroborate the HS triad composed of upregulated inflammation, altered epithelial differentiation, and dysregulated metabolism signaling. Upregulation of specific genes, such as KRT6, KRT16, serpin-family genes, and SPRR3 confirms the early involvement of hair follicles and the impairment of barrier function in HS lesioned skin. In addition, our results suggest that adipokines could be regarded as biomarkers of HS and metabolic-related disorders. Finally, the RNA-Seq variant calling identified several mutations in HS patients, suggesting potential new HS-related genes associated with the sporadic form of this disease. Overall, this study provides insights into the molecular pathways involved in HS and identifies potential HS-related biomarkers.

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.

New and Emerging Targeted Therapies for Hidradenitis Suppurativa

Hidradenitis suppurativa (HS) is a chronic, recurrent, inflammatory skin disease deriving from the hair follicles. The formation of inflammatory nodules, abscesses, fistulas, and sinus tracts is characterized by a large inflow of key pro-inflammatory mediators, such as IFN-γ, TNF-α, IL-1, IL-17, and IL-12/23. Adalimumab is currently the only Food and Drug Administration (FDA)- and European Medicines Agency (EMA)-approved biologic therapy for moderate to severe HS in adults and adolescents. However, the long-term effectiveness of this TNF-α inhibitor in HS patients has shown to be highly variable. This review aims to review the evidence for emerging therapies that target the main pro-inflammatory cytokines in HS pathogenesis. A review of the literature was conducted, using the PubMed and Google Scholar repositories, as well as Clinicaltrials.gov. Presently, the most promising biologics in phase III trials are anti-IL-17 antibodies, secukinumab, and bimekizumab. Furthermore, an anti-IL-1 biologic, bermekimab, is currently in phase II trials, and shows encouraging results. Overall, the clinical efficacies of all new targeted therapies published up to this point are limited. More studies need to be performed to clarify the precise molecular pathology, and assess the efficacy of biological therapies for HS.

Paradoxical Hidradenitis Suppurativa during Biologic Therapy, an Emerging Challenge: A Systematic Review

Hidradenitis suppurativa (HS) is a chronic, inflammatory skin disease usually occurring after puberty with painful, deep-seated, inflammatory lesions in the apocrine gland-bearing areas of the body. Although HS pathogenesis is still unproven, recent major research advantages have increased our knowledge of the mechanisms behind HS lesions. Particularly, follicular occlusion followed by follicular rupture has been shown to be crucial to HS development, leading to immune response activation, and resulting in typical clinical HS lesions. Moreover, an increased and imbalanced cytokine production, such as interleukin (IL) 17 and tumor necrosis factor (TNF) α, may play a role in HS. In recent years, paradoxical adverse events have been described during treatment. Since the recent increased use of biologic treatments in HS, an increased number of paradoxical HS occurrences have been reported. In this review, we analyzed all current data on paradoxical HS triggered by biological drugs.

Paradoxical Reactions to Biologicals in Chronic Inflammatory Systemic Diseases

BACKGROUND

Biological agents that contain substances affecting the immune system are increasingly being used to treat chronic inflammatory systemic diseases. Aside from the expected adverse effects, they can also induce unexpected paradoxical reactions (PR). A reaction is called paradoxical when a substance that is generally therapeutically effective induces the opposite of what is intended, with the new appearance or exacerbation of inflammatory changes in the skin and other organs.

METHODS

The paradoxical reactions that have been described since 1997 are presented here on the basis of the available literature on the main types of chronic inflammatory systemic disease, which was retrieved by a selective search in the PubMed and Google Scholar databases.

RESULTS

Many studies and registers to date contain no mention of paradoxical reactions. Anti- TNF-alpha treatment for patients with ankylosing spondylitis leads to paradoxical reactions in 19 per 1000 patient years, compared to 11 per 1000 patient years with conventional treatment; the corresponding frequency for paradoxical psoriasis in patients with other chronic inflammatory systemic diseases are 1.04-3.68 versus 1.45 per 1000 patient years. Paradoxical reactions tend to be more common with anti-TNF-alpha treatment than, for example, with the administration of ustekinumab, vedolizumab, and other agents. It is unclear whether some drugs have been noted to cause PR more commonly than others because of varying times since their approval, differences in immunogenicity, and differences between their target structures.

CONCLUSION

Paradoxical reactions induced by biological agents are a problem confronting physicians in multiple specialties. They need to be distinguished from infectious and neoplastic diseases and from autoimmune conditions of other types. The treatment options for paradoxical reactions include local treatment, symptomatic therapy, prednisolone administration, and the discontinuation or switching of the biological agent, although some patients will react with a further paradoxical reaction to a different biological agent that is used instead.

Paradoxical hidradenitis suppurativa in Crohn's disease patients receiving infliximab: a case report and review of literature

The introduction of TNF blockers in the therapeutic armamentarium of inflammatory bowel diseases (IBD) has largely advanced the way by which clinicians manage these disorders. However, some patients develop de novo immune-mediated diseases during the treatment. We here present the case of paradoxical hidradenitis suppurativa, a chronic inflammatory skin disease characterized by the development of recurrent nodules and abscesses in intertriginous areas, in a 20-year-old, nonsmoker, normal-weight women, with no family history of hidradenitis suppurativa or IBD, diagnosed with nonstricturing nonpenetrating ileocolonic Crohn's disease in 2013, during treatment with infliximab. Infliximab discontinuation was followed by a significant improvement of skin lesions. We also discuss 22 additional cases of paradoxical hidradenitis suppurativa in IBD patients on TNF antagonists reported in the literature with the aim to identify potential risk factors for the development of such a complication. All the patients had Crohn's disease, and the majority of them were women (19/23; 82.6%). All cases occurred during therapy with anti-TNF agents [14/23 (61%) patients were treated with adalimumab and 9/23 (39%) patients were treated with infliximab]. The therapeutic approach directed at maintaining/holding the undergoing biologic therapy is still uncertain. Further studies are needed to determine the most appropriate treatment choice toward ongoing biologic therapy.

[CME Dermatology 23: Hidradenitis suppurativa]

CME Dermatology 23: Hidradenitis suppurativa Abstract. Hidradenitis suppurativa (Acne inversa) is a chronic skin disease characterized by recurrent inflammatory nodules, abscesses, and scarring mainly in the intertriginous areas. The prevalence is estimated to be 0.05 to 4.1 % worldwide, with women being more commonly affected. The exact pathogenesis remains unknown, but hair follicle occlusion and inflammation seem to be the initiating events. Several epidemiological correlations with smoking and obesity as well as mutations in gamma secretase genes were described. The therapy depends on the extension of the disorder and should respect the current guidelines. Topical clindamycin is suitable for mild forms of the disease whereas moderate to severe disease requires systemic anti-inflammatory treatment. Surgical intervention is currently the only definitive treatment for hidradenitis suppurativa.

Tocilizumab and its usage for skin diseases

The monoclonal anti-IL6 receptor antibody called Tocilizumab is widely used by rheumatologists for joint diseases. Its application in dermatology has mainly concerned scleroderma and Systemic Sclerosis in the last years. The most varied skin diseases treated with tocilizumab, such as psoriasis, psoriatic arthritis, Behcet's Syndrome, Lupus, and the already mentioned scleroderma up to multi-organ syndromes with skin involvement will be discussed. At the same time, there have been several side reactions to the drug involving the skin forcing careful skin monitoring during treatment. Despite the evidence currently available in the appropriate literature, there is no formal recommendation for any of these diseases to use Tocilizumab for therapeutic purposes. The aim of this review was to collect all the main evidence on the use and involvement of the drug in dermatological practice in order to stimulate further research or hypothesize on possible therapeutic options.

Metabolic, pharmacokinetic, and toxicological issues of biologic therapies currently used in the treatment of hidradenitis suppurativa

INTRODUCTION

Hidradenitis suppurativa is a chronic, relapsing, debilitating inflammatory dermatologic disease of the terminal hair follicles at intertriginous sites clinically characterized by painful inflammatory nodules, abscesses, draining sinus tracts, and dermal fibrosis. The management of hidradenitis suppurativa is a challenge and usually consists of both medical and surgical approaches, which must often be combined for best outcome. The introduction of biological therapies, specifically TNFα-inhibitors such as adalimumab, has profoundly changed the therapeutic armamentarium of the disease.

AREAS COVERED

The PubMed database was searched using combinations of the following keywords: hidradentis suppurativa, biologic therapy, TNF-α inhibitors, adalimumab, etanercept, infliximab, certolizumab pegol, golimumab, adverse effects, pharmacodynamics, pharmacology, adverse events, pharmacokinetics, drug interaction. This article reviews and updates the chemistry, pharmacokinetics, mechanism of action, adverse effects, drug interactions of on-label and off-label use of TNF-α inhibitors in HS.

EXPERT OPINION

Biologic agents, particularly adalimumab, exhibit clinical efficacy in patients with hidradenitis suppurativa. Careful patient selection and close monitoring during treatment are mandatory to provide safe and effective use of the TNF-α inhibitor. Familiarity with biologic agents is crucial because these agents could become a consolidated treatment option in the clinician's therapeutic approaches.

Immunopathogenesis of hidradenitis suppurativa and response to anti-TNF-α therapy

Hidradenitis suppurativa (HS) is a highly prevalent, morbid inflammatory skin disease with limited treatment options. The major cell types and inflammatory pathways in skin of patients with HS are poorly understood, and which patients will respond to TNF-α blockade is currently unknown. We discovered that clinically and histologically healthy appearing skin (i.e., nonlesional skin) is dysfunctional in patients with HS with a relative loss of immune regulatory pathways. HS skin lesions were characterized by quantitative and qualitative dysfunction of type 2 conventional dendritic cells, relatively reduced regulatory T cells, an influx of memory B cells, and a plasma cell/plasmablast infiltrate predominantly in end-stage fibrotic skin. At the molecular level, there was a relative bias toward the IL-1 pathway and type 1 T cell responses when compared with both healthy skin and psoriatic patient skin. Anti-TNF-α therapy markedly attenuated B cell activation with minimal effect on other inflammatory pathways. Finally, we identified an immune activation signature in skin before anti-TNF-α treatment that correlated with subsequent lack of response to this modality. Our results reveal the fundamental immunopathogenesis of HS and provide a molecular foundation for future studies focused on stratifying patients based on likelihood of clinical response to TNF-α blockade.

Contribution of plasma cells and B cells to hidradenitis suppurativa pathogenesis

Hidradenitis suppurativa (HS) is a debilitating chronic inflammatory skin disease characterized by chronic abscess formation and development of multiple draining sinus tracts in the groin, axillae, and perineum. Using proteomic and transcriptomic approaches, we characterized the inflammatory responses in HS in depth, revealing immune responses centered on IFN-γ, IL-36, and TNF, with lesser contribution from IL-17A. We further identified B cells and plasma cells, with associated increases in immunoglobulin production and complement activation, as pivotal players in HS pathogenesis, with Bruton’s tyrosine kinase (BTK) and spleen tyrosine kinase (SYK) pathway activation as a central signal transduction network in HS. These data provide preclinical evidence to accelerate the path toward clinical trials targeting BTK and SYK signaling in moderate-to-severe HS.

B-cells and plasma cells are critical pathogenic cell populations in chronic Hidradenitis Suppurativa and are potential therapeutic targets.

Hidradenitis Suppurativa as a Paradoxical Side Effect to the Use of Adalimumab in Patients with Crohn's Disease?

Background

Hidradenitis suppurativa is a chronic inflammatory skin disorder associated with inflammatory bowel disease. However, it can arise as a paradoxical side effect of anti-TNF treatment.

Methods

The article reports on three patients with Crohn's disease who developed hidradenitis suppurativa during the treatment with adalimumab.

Results

Case 1: A 38-year-old female exhibited an infiltrative lesion in the inguinal region and vulva, consistent with hidradenitis suppurativa, after three months of adalimumab. These lesions were treated with partial vulvectomy. Case 2: After adalimumab treatment, a 27-year-old female, originally diagnosed with ileocolonic Crohn's disease, went into clinical and endoscopic remission. The patient eventually presented two hyperchromic nodules in the inguinal region, which were diagnosed as hidradenitis suppurativa. The patient showed improvement after treatment with oral doxycycline and local therapy. Case 3: A 34-year-old female with fistulizing and stenosing ileocolonic Crohn's disease, started adalimumab in 2010, with optimization in 2015. One year after, the patient developed bilateral, erythematous, hardened, inguinal nodulations with purulent drainage, consistent with hidradenitis suppurativa. Treatment with oral doxycycline, fusidic acid, and infiltration with triamcinolone resulted in partial improvement of the lesions. In 2018, the lesions deteriorate. The patient underwent surgical treatment.

Conclusion

Patients with inflammatory bowel disease are more likely to the development of other mediated inflammatory diseases, such as hidradenitis suppurativa. Hidradenitis suppurativa may appear as a paradoxical reaction to anti-TNF therapy. Clinical teams must be aware of this type of complication. Early diagnosis and treatment are essential for controlling the disease and preventing the onset of complications.

A case paradoxical hidradenitis suppurativa with janus kinase inhibitor, literature review and pooled analysis of biological agent-induced HS

Hidradenitis suppurativa (HS) is a debilitating chronic inflammatory skin disease. Biological therapy has revolutionized it's the treatment. Paradoxical HS occur with various biological and targeted agents. We report a patient with juvenile rheumatoid arthritis who developed HS after 6 months of tofacitinib therapy. A comprehensive literature review identified 43 cases of paradoxical HS among patients on biological and targeted agents. Pooled analysis of the cases showed Crohn's disease 18(41.8%) and RA 9(20.9%) as commonest indications for biological therapy. Adalimumab 20(46.5%) followed by infliximab 9(20.9%) were the commonest offending agents. Duration of biological treatment prior to HS manifestation was 12(1-120) months. Smoking 21(48.8%) and overweight or obese 20(46.5%) were most frequent HS risk factors. Fourteen (32.6%) patients had a second paradoxical event, 11(25.6%) developed psoriasis and 4(9.3%) Crohn's disease. Presence of ≥1 risk factor for HS, continuation of the implicated biological agent and occurrence of more than one paradoxical event were factors associated with poor paradoxical HS outcome.

Dermatological complications of therapy with biologics in inflammatory autoimmune diseases

BACKGROUND AND OBJECTIVE

Cutaneous adverse events (CAEs) occur in up to 10 % of patients with immune-mediated inflammatory disease (IMID) treated with antitumor necrosis factor (TNF)α agents. The aim of this clinical study was to track and observe the course of CAEs in all biologic therapies.

PATIENTS AND METHODS

The population for this study consisted of patients with CAEs under biologic therapy who were examined by experienced board-certified dermatologists in the outpatient department of the University Hospital Essen, Department of Dermatology.

RESULTS

Altogether 39 patients with a total of 45 CAEs were included in this study. In 60 % of the cases a form of paradoxical psoriasis was diagnosed. Two thirds (66.6 %) of the patients with CAEs were diagnosed with an underlying inflammatory bowel disease (IBD). TNFα antagonists were the triggering agents in about 95 % of the cases. Changes in biological therapy were required in nearly half of the cases (46.2 %). Almost 90 % of the patients had either a complete (42.1 %) or a partial response (47 %).

CONCLUSIONS

Management of CEAs under biological therapy can be challenging in clinical practice. Case discussions between gastroenterologists, rheumatologists and dermatologists should be undertaken to best manage patients with CAEs and avoid unnecessary changes of therapy.

Skin Manifestations in Pediatric Patients Treated With a TNF-Alpha Inhibitor for Inflammatory Bowel Disease: A Retrospective Study [Formula: see text]

BACKGROUND

Tumor necrosis factor (TNF) alpha inhibitors (anti-TNF) are effective in the treatment of inflammatory bowel disease (IBD) as well as psoriasis. Their increasing use has raised the identification of cutaneous side effects (CSEs). Evidence in children is limited.

OBJECTIVES

The objective of this study is to describe CSEs of anti-TNF treatment in a pediatric population with IBD.

METHODS

This is a retrospective single-center study of children with IBD under anti-TNF treatment between 2013 and 2016. A total of 40 patients with CSEs related to anti-TNF were referred to our pediatric dermatology clinic. A control group was randomly selected from patients receiving anti-TNF for IBD, who were referred to the dermatology clinic for other conditions unrelated to anti-TNF.

RESULTS

Of 343 patients with IBD, 40 (11.3%) presented CSEs potentially related to the treatment. No differences in sex, age, and underlying disease were found between those with and without CSEs. The most frequent CSEs were psoriasiform eruptions (41%) which were more exudative than usual, located especially in skin folds and on the scalp; skin infections (20%); and eczematous eruptions (10%). Only 5% of patients changed or discontinued the current anti-TNF because of CSEs.

CONCLUSION

This is one of the largest pediatric cohorts of IBD patients with CSEs. Psoriasiform eruptions were the most common CSEs, with predilection for skin folds and scalp, and frequent superimposed bacterial infection. Topical and/or systemic antibiotics were required in addition to topical corticosteroids in 25% of patients. The rate of discontinuation of anti-TNF therapy due to CSEs was low.

Paradoxical Hidradenitis Suppurativa in Patients Receiving TNF-α Inhibitors: Case Series, Systematic Review, and Case Meta-Analysis

BACKGROUND/AIMS

TNF-α inhibitors represent the most advanced approved therapeutic option for moderate and severe forms of hidradenitis suppurativa (HS). However, in recent years, cases of paradoxical HS secondary to the use of these biological drugs have been described, with very few cases reported in the literature. The aims of this study are (1) to present 2 new cases of paradoxical HS and (2) to perform a systematic review of scientific evidence regarding paradoxical HS with TNF-α inhibitors.

MATERIAL AND METHODS

This is a retrospective study in which we searched all the cases of paradoxical HS secondary to the use of TNF-α inhibitors published in the literature and included two additional cases observed in our clinical practice.

RESULTS

A total of 34 patients under TNF-α inhibitor treatment were included (adalimumab = 21; infliximab = 9; etanercept = 4). The median delay from exposure to TNF-α inhibitor and the development of paradoxical HS was 12 months (range 1-72). The majority of patients were Hurley stage II (58.8%). Clinical improvement and complete remission were more frequent when the TNF-α inhibitor was stopped or switched to another biological agent with a different therapeutic target rather than maintenance or change to another TNF-α inhibitor.

CONCLUSIONS

Paradoxical HS is an unusual adverse effect of TNF-α inhibitors. When this adverse effect appears, interruption or substitution of treatment is associated with a better clinical outcome.

Secukinumab-induced paradoxical hidradenitis suppurativa

Paradoxical reactions during treatment with biological agents may be defined as an appearance or exacerbation of a pathological condition that usually responds to this class of drug. Typical examples of paradoxical adverse effect are, among others, palmoplantar pustular and psoriasiform reactions or HS, in patients during a treatment of rheumatoid arthitis or IBD mainly. A few reports have been described an exacerbation of psoriasis1, palmoplantar pustular, or pustular psoriasis eruption with secukinumab. Marasca et al. highlights the immunological complexity that surrounds autoinflammatory diseases showing the potential double pathogenetic face of secukinumab in HS, describing a case of secukinumab-induced HS and a case of HS caused by adalimumab treatment and controlled by secukinumab therapy. Real world evidence and results from clinical trials with secukinumab for HS, will possibly show the real role that anti-IL-17 drugs play in this complex disease.

Paradoxical Skin Reactions to Biologics in Patients With Rheumatologic Disorders

Targeted immune-modulating treatment with biological agents has revolutionized the management of immune-mediated inflammatory diseases, including rheumatologic conditions. The efficacy and tolerability of biological agents, from the initial tumour necrosis factor (TNF)-α inhibitors to the new anti-cytokine monoclonal antibodies, have dramatically changed the natural history of debilitating conditions such as rheumatoid arthritis and seronegative spondyloarthropathies. The widening use of biologics across several rheumatologic diseases has been associated with a new class of adverse events, the so-called paradoxical reactions. These events are inflammatory immune-mediated tissue reactions, developing paradoxically during treatment of rheumatologic conditions with targeted biologics that are commonly used for treating the idiopathic counterparts of these drug-induced reactions. The skin is frequently involved, and, even if considered rare to uncommon, these cutaneous manifestations are an important cause of biologic agent discontinuation. TNF-α antagonist-induced psoriasis, which can manifest de novo or as exacerbation of a pre-existing form, is the prototypic and most frequent paradoxical skin reaction to biologics while other reactions, such as eczematous and lichenoid eruptions, hidradenitis suppurativa, pyoderma gangrenosum, Sweet’s syndrome and granulomatous skin diseases, occur much more rarely. Management of these reactions consists of topical or systemic skin-directed therapies, depending on the severity and extension of the cutaneous picture, and it is generally associated with switching over to other disease-modifying regimens for treating the underlying rheumatologic condition. Here, we review in detail the current concepts and controversies on classification, pathogenesis and clinical management of this new class of cutaneous adverse events induced by biologics in rheumatologic patients.

Paradoxical Reactions to Biologic Therapy in Psoriasis: A Review of the Literature

Biologic drugs, which are molecules designed to act on specific immune system targets, have been shown to be very effective in treating various dermatological, rheumatological, and systemic diseases. As a group, they have an acceptable safety profile, but their use has been associated with the onset of both systemic and organ-specific inflammatory conditions. True paradoxical reactions are immune-mediated disorders that would usually respond to the biologic agent that causes them. There is still debate about whether certain other adverse reactions can be said to be paradoxical. The hypotheses proposed to explain the pathogenesis of such reactions include an imbalance in cytokine production, with an overproduction of IFN-α and altered lymphocyte recruitment and migration (mediated in part by CXCR3), and the production of autoantibodies. Some biologic therapies favor granulomatous reactions. While most of the paradoxical reactions reported have been associated with the use of TNF-α inhibitors, cases associated with more recently introduced biologic therapies -such as ustekinumab, secukinumab, and ixekizumab- are increasingly common. The study of paradoxical adverse events not only favors better management of these reactions in patients receiving biologic therapy, but also improves our knowledge of the pathogenesis of chronic inflammatory diseases and helps to identify potential therapeutic targets.

Deep Granuloma Annulare Mimicking Inflamed Cysts in a Teenager

We describe deep granuloma annulare (DGA) of the forehead mimicking inflamed cysts. Reactive inflammation and sterile purulent drainage may be an underrecognized feature of DGA.

Paradoxical reactions under TNF-α blocking agents and other biological agents given for chronic immune-mediated diseases: an analytical and comprehensive overview

Paradoxical adverse events (PAEs) have been reported during biological treatment for chronic immune-mediated diseases. PAEs are defined as the occurrence during biological agent therapy of a pathological condition that usually responds to this class of drug. A wide range of PAEs have been reported including dermatological, intestinal and ophthalmic conditions, mainly with antitumour necrosis factor α (TNF-α) agents. True PAEs include psoriasis, Crohn's disease and hidradenitis suppurativa. Other PAEs may be qualified as borderline and include uveitis, scleritis, sarcoidosis and other granulomatous diseases (granuloma annulare, interstitial granulomatous dermatitis), vasculitis, vitiligo and alopecia areata. Proposed hypotheses to explain these PAEs include an imbalance in cytokine production, the differential immunological properties between the monoclonal antibodies and TNF-α soluble receptor, an unopposed type I interferon production and a shift towards a Th1/Th2 profile. Data from registries suggest that the risk for paradoxical psoriasis is low and non-significant. We discuss management of these PAEs, which depends on the type and severity of the adverse events, pre-existing treated conditions and the possibility of alternative therapeutic options for the underlying disease. Paradoxical adverse events are not restricted to anti-TNF-α agents and close surveillance of new available biological drugs (anti-interleukin-17/23, anti-integrin) is warranted in order to detect the occurrence of new or as yet undescribed events.