Immunological response in Stevens-Johnson syndrome and toxic epidermal necrolysis

TNF-α inhibitors as therapy for drug-induced severe cutaneous adverse reactions: a case series

Background: Severe cutaneous adverse reactions (SCARs) including acute generalized exanthematous pustulosis (AGEP), drug reaction with eosinophilia and systemic symptoms (DRESS), Stevens-Johnson syndrome (SJS) and its related diseases, and toxic epidermal necrolysis (TEN) are of great concern due to their high mortality rates. While systemic corticosteroids have been widely used to treat SCARs, their efficacy has been debated due to the increased risk of infection. In recent years, tumor necrosis factor (TNF)-α inhibitors have emerged as a new therapeutic option.

Objectives: This study aimed to report the clinical outcomes of different types of SCARs treated with TNF-α inhibitors.

Methods: Since 2020, our department has treated 4 SCAR patients, aged 20-54 years, with 1 diagnosed with AGEP and 3 with TEN. All patients received TNF-α inhibitor therapy, including etanercept and adalimumab.

Results: All 4 patients achieved successful outcomes, with rapid recovery of skin lesions and mucosal involvement, and no subsequent complications. Notably, one patient improved after initial corticosteroid and intravenous immunoglobulin treatment failed.

Discussion: The pathogenesis of SCARs involves T cell-mediated keratinocyte apoptosis, in which TNF-α plays a crucial role. TNF-α inhibitors, by downregulating the TNF-α signaling pathway, have demonstrated potential in the treatment of SCARs. However, large-scale clinical trials supporting their efficacy are still lacking, and their use remains limited, requiring a careful balance of treatment risks and benefits.

Stevens-Johnson syndrome and toxic epidermal necrolysis: Updates in pathophysiology and management

ABSTRACT

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are life-threatening conditions characterized by extensive detachment of the epidermis and mucous membranes. These severe disorders carry a high mortality rate, and their pathogenesis remains largely unclear. Furthermore, optimal therapeutic strategies for SJS/TEN remain a subject of ongoing debate. Early diagnosis of SJS/TEN is challenging, and reliable biomarkers for diagnosis or severity prediction have not been firmly established. Certain drugs, such as carbamazepine and allopurinol, have shown a strong association with specific human leukocyte antigen (HLA) types. Recently, the potential benefits of HLA screening prior to administering these drugs to reduce the incidence of SJS/TEN have been explored. Epidermal cell death in SJS/TEN lesions is caused by extensive apoptosis, primarily through the Fas-Fas ligand (FasL) and perforin/granzyme pathways. Our findings suggest that necroptosis, a form of programmed necrosis, also contributes to epidermal cell death. Annexin A1, released from monocytes, interacts with the formyl peptide receptor 1 to induce necroptosis. Several biomarkers, such as CC chemokine ligand (CCL)-27, interleukin-15, galectin-7, receptor-interacting protein kinases 3 (RIP3), and lipocalin-2, have been identified for diagnostic and prognostic purposes in SJS/TEN. Supportive care is recommended for treating SJS/TEN, but the efficacy of various therapeutic options-including systemic corticosteroids, intravenous immunoglobulin, cyclosporine, and tumor necrosis factor-α antagonists-remains controversial. Recent studies have investigated the potential benefits of tumor necrosis factor-α antagonists. In this review, we discuss recent advances in the understanding and management of SJS/TEN.

Real-world safety of Levetiracetam: Mining and analysis of its adverse drug reactions based on FAERS database

INTRODUCTION

Levetiracetam is a relatively new and widely utilized anti-seizure medication; however, limited information is available regarding its adverse effects. This study aims to thoroughly investigate, evaluate, and present evidence on the safety profile of Levetiracetam, relying on data from the FDA Adverse Event Reporting System (FAERS) database to facilitate informed clinical decision-making.

METHODS

We employed various statistical measures, including Reporting Odds Ratio (ROR), Proportionate Reporting Ratio (PRR), and analysis by the Medicines and Healthcare Products Regulatory Agency (MHRA), to identify signals of adverse reactions associated with Levetiracetam. Positive signals consistent with Designated Medical Event (DME) were singled out for focused comparison and discussion.

RESULTS

The analysis of 26,182 adverse events linked to Levetiracetam as the primary suspected drug revealed 692 positive signals spanning 22 System Organ Classes (SOCs). Nervous system disorders were the most frequently reported, followed by psychiatric disorders, and general disorders and administration site conditions. 11 positive signals consistent with Preferred Terms (PTs) in DME were identified, predominantly concentrated in 6 SOCs. Among these, rhabdomyolysis, Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), drug reaction with eosinophilia and systemic symptoms (DRESS) exhibited relatively large values of A, ROR, and Chi-squared. Additionally, PTs related to spontaneous abortion, drug interaction, urethral atresia, ventricular septal defect, and atrial septal defect showed significant strength.

CONCLUSIONS

The study indicates that Levetiracetam carries a potential risk of causing rhabdomyolysis, SJS, TEN, DRESS as well as spontaneous abortion. Signals related to drug interaction, urethral atresia, ventricular septal defect, and atrial septal defect warrant heightened attention in clinical use.

A Case Report of Cefixime, Paracetamol, and Nimesulide Induced Toxic Epidermal Necrolysis in a Woman with Dengue Infection without any Other Associated Comorbidities

BACKGROUND

Toxic Epidermal Necrolysis (TEN) is a rare, acute, and life-threatening mucocutaneous disease that occurs after the administration of certain drugs, resulting in extensive keratinocyte cell death, skin involvement at the dermal-epidermal junction, and extensive bullous skin eruptions and sloughing. Many published case reports have observed the presence of fever with a viral infection, drug, and/or genetic association as a possible trigger for TEN but associated with other comorbidities. Physicians still struggle to predict which individuals could be predisposed to TEN. The case report that we present had a history of multiple drug intake and fever due to dengue virus infection but was not associated with any other comorbidity.

CASE PRESENTATION

We present an unusual case of a 32-year-old woman of Western Indian origin who had developed dengue infection and suffered toxic epidermal necrolysis following a five-day course of a third-generation cephalosporin antibiotic, cefixime and a three-day course of 2 analgesic drugs, paracetamol (acetaminophen), and nimesulide, with the adverse event occurring on the fifth day of the dengue infection. The offending drugs were stopped, and patient survived with supportive management and hydration.

CONCLUSION

The presence of comorbidities may not always be the triggering factor for TEN, though it can affect patient outcomes. Rational drug use is always recommended for patient care. Further research is required to understand the pathomechanism behind the viral-drug-gene interaction.

Phenytoin-Induced Toxic Epidermal Necrolysis

Toxic epidermal necrolysis (TEN) is a rare fatal mucocutaneous blistering disorder that can have varied underlying triggers. The percentage of body surface area (BSA) that is impacted by erosive blistering is what separates it from Steven Johnson syndrome (SJS), both of which have the same underlying pathogenesis and are thought to exist on a continuum of disease with TEN being the more serious of the two. Medications are the most frequent cause of TEN/SJS and typically cause disease in both adults and children within eight weeks; however, the median exposure window is four days to four weeks. Nonsteroidal anti-inflammatory drugs, allopurinol, anticonvulsants including lamotrigine, phenytoin, levetiracetam and carbamazepine, antimicrobial sulfonamides, and the antiviral nevirapine are examples of medications that frequently cause TEN/SJS. Here, we are reporting a case of phenytoin-induced TEN highlighting the patient's excellent response to immunomodulating treatment despite 100% involvement of the BSA.

Pembrolizumab-Associated Stevens-Johnson Syndrome in a Patient With Metastatic Non-small Cell Lung Cancer: A Case Report

Pembrolizumab is a monoclonal antibody that binds to the programmed cell death-1 (PD-1) receptor and is approved for the treatment of several malignancies. We present a rare case of Stevens-Johnson syndrome (SJS) occurring in a 75-year-old female 14 days after receiving the first dose of pembrolizumab therapy to treat stage IV non-small cell carcinoma of the lungs with metastasis to the brain. Although pruritus and papular, erythematous rashes are documented after its use, severe reactions such as SJS and toxic epidermal necrolysis (TEN) are rarely seen in clinical practice. In addition to supportive care, the patient also received intravenous immunoglobulin (IVIG) and corticosteroid therapy and responded well to the therapy. Nearly complete re-epithelialization was achieved four weeks after the start of skin lesions. This case highlights a rare phenomenon of SJS- and TEN-associated adverse reactions following treatment with pembrolizumab.

Photodistributed Stevens-Johnson syndrome and toxic epidermal necrolysis: a systematic review and proposal for a new diagnostic classification

BACKGROUND

Ultraviolet radiation (UVR) exposure is commonly reported as a risk factor for Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). However, minimal evaluation of photo-induced SJS/TEN has been conducted. Thus, this review identifies all cases of SJS/TEN that are linked to an acute exposure of UVR and outlines the unifying characteristics of these cases. Furthermore, the theoretical pathogenesis, differential diagnoses, and proposed diagnostic criteria are defined.

METHODS

PubMed, Google Scholar, and other databases and websites were searched from inception to September 2021 to identify studies that met inclusion criteria. The following keywords were utilized: "Stevens-Johnson syndrome" and "toxic epidermal necrolysis" with "ultraviolet," "photodistributed," "photo-induced," "photosensitivity," and "photo." One reviewer assessed study characteristics, with confirmation by a second. The risk of bias was assessed independently by another.

RESULTS

Thirteen patient cases were identified, all reporting ultraviolet radiation prior to rash onset and an underlying causal drug. Case classifications included 7/13 SJS and 6/13 TEN. All cases described the rash as photodistributed with UVR exposure prior to rash onset (delay of 1-3 days) and a causal drug. 10 cases provided evidence that the photodistributed rash lacked linear demarcation (as in a sunburn) with satellite target-like lesions. No cases described a flu-like prodrome.

DISCUSSION

Mucositis, palmar and plantar rash, a positive Nikolsky sign, and a prolonged disease course can help distinguish from photosensitive reactions, while a negative direct immunofluorescence test is important to distinguish from other photo-induced disorders.

CONCLUSION

Physicians should be aware that UVR may precipitate SJS/TEN in patients taking susceptible drugs. After a 24-h delay from UVR exposure, a non-distinct, photodistributed rash appears with no flu-like prodrome and progresses for at least 48 h to include vesiculobullous eruptions and mucous membrane involvement. Photodistributed SJS/TEN appears to be photo-drug-induced with a unique onset and rash presentation that should be recognized as a distinct diagnosis.

TNF-α‒Mediated Keratinocyte Expression and Release of Matrix Metalloproteinase 9: Putative Mechanism of Pathogenesis in Stevens‒Johnson Syndrome/Toxic Epidermal Necrolysis

Stevens‒Johnson syndrome and toxic epidermal necrolysis (SJS/TEN) are severe cutaneous adverse drug reactions characterized by widespread keratinocyte cell death and epidermal detachment. At present, there is little understanding of how the detachment occurs or how it is abrogated by the TNF-α inhibitor etanercept, an effective SJS/TEN treatment. RNA sequencing was used to identify upregulated transcripts in formalin-fixed paraffin-embedded SJS/TEN skin biopsies. Epidermal matrix metalloproteinase 9 (MMP9) expression was assessed by immunohistochemistry in skin biopsies and cultured human skin explants exposed to serum from patients with cutaneous adverse drug reactions. TNF-α‒induced MMP9 expression and activity and its abrogation by etanercept were determined using the HaCaT immortalized keratinocyte cell line. Epidermal MMP9 expression was significantly higher in SJS/TEN skin (70.6%) than in healthy control skin (0%) (P = 0.0098) and nonbullous skin reactions (10.7%) (P = 0.0002). SJS/TEN serum induced significant MMP9 expression and collagenase activity in healthy skin explants, which was reduced by etanercept. Etanercept was also able to negate the TNF-α‒induced MMP9 expression in the HaCaT cell line. Data suggest that elevated epidermal MMP9 expression and collagenase activity are a putative pathogenic mechanism in SJS/TEN, which is limited by etanercept. Modulation of MMP9 expression and activity represents, to our knowledge, a previously unreported therapeutic target for the treatment of SJS/TEN.

REDDA: Integrating multiple biological relations to heterogeneous graph neural network for drug-disease association prediction

Computational drug repositioning is an effective way to find new indications for existing drugs, thus can accelerate drug development and reduce experimental costs. Recently, various deep learning-based repurposing methods have been established to identify the potential drug-disease associations (DDA). However, effective utilization of the relations of biological entities to capture the biological interactions to enhance the drug-disease association prediction is still challenging. To resolve the above problem, we proposed a heterogeneous graph neural network called REDDA (Relations-Enhanced Drug-Disease Association prediction). Assembled with three attention mechanisms, REDDA can sequentially learn drug/disease representations by a general heterogeneous graph convolutional network-based node embedding block, a topological subnet embedding block, a graph attention block, and a layer attention block. Performance comparisons on our proposed benchmark dataset show that REDDA outperforms 8 advanced drug-disease association prediction methods, achieving relative improvements of 0.76% on the area under the receiver operating characteristic curve (AUC) score and 13.92% on the precision-recall curve (AUPR) score compared to the suboptimal method. On the other benchmark dataset, REDDA also obtains relative improvements of 2.48% on the AUC score and 4.93% on the AUPR score. Specifically, case studies also indicate that REDDA can give valid predictions for the discovery of -new indications for drugs and new therapies for diseases. The overall results provide an inspiring potential for REDDA in the in silico drug development. The proposed benchmark dataset and source code are available in https://github.com/gu-yaowen/REDDA.

Combined use of cyclosporine in the treatment of Stevens-Johnson syndrome/toxic epidermal necrolysis

The exact efficacy of cyclosporine in the treatment of Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) still needs evidence from more clinical data. This study was designed to compare the effectiveness and side-effects of combined use of cyclosporine in the treatment TEN with glucocorticoids (GC)/i.v. immunoglobulin G (IVIG). A total of 46 patients with SJS/TEN were enrolled and classified into two groups based on the therapeutic drugs used. Clinical characteristics, interventions, outcomes, and disease progressions were collected and compared between the two groups. In our cohort, seven patients eventually died and the overall fatality rate was 15.2%, but there was no difference between the two groups (p = 0.557). On discharge, the median SCORe of Toxic Epidermal Necrosis (SCORTEN) fell from 2.0 at admission to 1.0 and the median body surface area detached fell from 32.0% at admission to 9.5%. Patients in the cyclosporine group had a higher rate of re-epithelialized area than patients in the non-cyclosporine group (p < 0.05). Cyclosporine significantly reduced the length of stay (19.0 vs. 13.0 days, p = 0.019) and the rate of systemic infection (71.4% vs. 36.0%, p = 0.017) compared with the non-cyclosporine group. SCORTEN was the only significant risk factor for death and the risk ratio was 1.96 (1.17-3.31, p = 0.011). Conclusively, the combined use of cyclosporine could reduce the occurrence of systemic infection and accelerate the re-epithelialization.

Stevens-Johnson syndrome and toxic epidermal necrolysis: a systematic review and meta-analysis

OBJECTIVE

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare and severe skin and mucosal reactions that are associated with high mortality. Despite the severity, an evidence-based treatment protocol for SJS/TEN is still lacking.

METHOD

In this systematic review and meta-analysis, the PubMed database was searched using the following terms: [Stevens-Johnson syndrome] OR [toxic epidermal necrolysis] AND [therapy] OR [treatment] over a 20-year period (1999-2019) in the German and English language. All clinical studies reporting on the treatment of SJS/TEN were included, and epidemiological and diagnostic aspects of treatment were analysed. A meta-analysis was conducted on all comparative clinical studies that met the inclusion criteria.

RESULTS

A total of 88 studies met the inclusion criteria, reporting outcomes in 2647 patients. Treatment was either supportive or used systemic corticosteroid, intravenous immunoglobulin, plasmapheresis, cyclosporine, thalidomide or cyclophosphamide therapy. The meta-analysis included 16 (18%) studies, reporting outcomes in 976 (37%) patients. Systemic glucocorticoids showed a survival benefit for SJS/TEN patients in all analyses compared with other forms of treatment. Cyclosporine treatment also showed promising results, despite being used in a small cohort of patients. No beneficial effects on mortality could be demonstrated for intravenous immunoglobulins.

CONCLUSION

Glucocorticoids and cyclosporine may be tentatively recommended as the most promising immunomodulatory therapies for SJS/TEN, but these results should be investigated in future prospective controlled trials.

Differential expression of tear film cytokines in Stevens-Johnson syndrome patients and comparative review of literature

To investigate the differential expression of tear cytokine levels among chronic Stevens–Johnson syndrome (SJS) patients to better understand the role of significantly altered cytokines in disease development. Tear samples were collected using Schirmer strips in 24 eyes of chronic SJS, 24 eyes of age and gender-matched controls, and 14 eyes of aqueous deficiency dry eye disease (DED) patients. The cytokine analysis was performed among 18 analytes which include pro-inflammatory, anti-inflammatory factors, and ELR-negative CXC chemokines. String analysis was performed for the significantly altered cytokines to understand their co-expression and role in the disease development. Additionally, a literature review was conducted to identify the signature cytokines present in chronic SJS tears. The differential expression of IL-6 (p ≤ 0.029), CXCL8/IL-8 (p ≤ 0.009), IL-1β (p ≤ 0.041), IL-2 (p ≤ 0.025), IL-10 (p ≤ 0.053), and CXCL-10 (p ≤ 0.044) were observed in chronic SJS patients and healthy controls. Whereas, IL-6 (p ≤ 0.029), CXCL8/IL-8 (p ≤ 0.058), CCL4 (p ≤ 0.056), GM-CSF (p ≤ 0.0001) IL-10 (p ≤ 0.025), and CXCL-10 (p ≤ 0.010), were differentially expressed in SJS as compared to severe DED patients. String analysis of the significantly altered cytokines revealed the involvement of several biological processes including the chronic inflammatory response, nitric oxide synthesis, angiogenesis, and cellular response to drugs. Among all the cytokines evaluated, the expression of CXCL8/IL-8 and CXCL10 levels were consistently reported in the literature. There was a differential expression of tear cytokines in SJS when compared to DED and healthy controls. The differential expression of CXCL8/IL-8 and CXCL10 was in line with existing literature and their role in chronic SJS pathogenesis merits further evaluation.

Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis: A Review of Diagnosis and Management

Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) are rare diseases that are characterized by widespread epidermal necrosis and sloughing of skin. They are associated with significant morbidity and mortality, and early diagnosis and treatment is critical in achieving favorable outcomes for patients. In this scoping review, Excerpta Medica dataBASE and PubMed were searched for publications that addressed recent advances in the diagnosis and management of the disease. Multiple proteins (galectin 7 and RIP3) were identified that are promising potential biomarkers for SJS/TEN, although both are still in early phases of research. Regarding treatment, cyclosporine is the most effective therapy for the treatment of SJS, and a combination of intravenous immunoglobulin (IVIg) and corticosteroids is most effective for SJS/TEN overlap and TEN. Due to the rare nature of the disease, there is a lack of prospective, randomized controlled trials and conducting these in the future would provide valuable insights into the management of this disease.

Whole-Exome Sequencing in Patients Affected by Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis Reveals New Variants Potentially Contributing to the Phenotype

Background

Adverse drug reactions (ADRs) are frequent occurring events that can essentially be defined as harmful or unpleasant symptoms secondary to the use of a medicinal product. ADRs involve a wide spectrum of clinical manifestations ranging from minor itching and rash to life-threatening reactions. Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare ADRs. SJS-TEN may be considered a polygenic pathology due to additive/epistatic effects caused by sequence variants in numerous genes. Next-generation sequencing (NGS) represents a potentially interesting exploration tool in such scenario as it facilitates the simultaneous analysis of large genomic regions and genes at affordable cost.

Methods

The present study has involved using whole-exome sequencing (WES) for the first time on SJS-TEN patients. It involved robust and innovative multistep bioinformatics analysis focusing on 313 candidate genes potentially participating in the disease’s aetiology, specific drugs’ metabolism and gene regulation.

Results

We identified combinations of frequently occurring and rare variants that may contribute to the disease’s pathogenesis. Depending on the specific drug being taken, different variants (and alleles) in NAT2, CYP2D8, CYP2B6, ABCC2, UGT2B7 and TCF3 were identified as coherent candidates representing potential future markers for SJS-TEN.

Conclusion

The present study proposed and has described (for the first time) a large-scale genomic analysis of patients affected by SJS-TEN. The genes and variants identified represent relevant candidates potentially participating in the disease’s pathogenesis. Corroborating that proposed by others, we found that complex combinations of frequently occurring and rare variants participating in particular drug metabolism molecular cascades could be associated with the phenotype. TCF3 TF may be considered a coherent candidate for SJS-TEN that should be analysed in new cohorts of patients having ADRs.

Drug-related Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis: A Review

Introduction

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare, life-threatening, allergic reactions affecting the skin and mucous membranes. SJS is considered to be a milder form with less than 10% of body surface area (BSA) involvement. We report successful management of two cases of SJS and TEN. Firstly, a case of a 24-year-old female who presented with rashes over face, chest, and upper limbs after the oral intake of ciprofloxacin and local application of moxifloxacin eye drops. She developed high-grade fever and difficulty in breathing requiring intubation and lung-protective mechanical ventilation and was treated with high-dose methylprednisolone, azithromycin, soframycin skin dressings, and topical ocular antibiotics. Secondly, another case of a 16-year-old female who developed bullous eruptions over the trunk, arms, hands, face, and sole involving 60% of BSA, after oral intake of albendazole. She was diagnosed as TEN and successfully managed with sterile silver nitrate, soframycin dressings, and antibiotics.

Key message

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are life-threatening, allergic reactions affecting the skin and mucous membranes. Early identification, withdrawal of the suspected drug, and early transfer to a specialized center decrease mortality.

How to cite this article

Arora R, Pande RK, Panwar S, Gupta V. Drug-related Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis: A Review. Indian J Crit Care Med 2021;25(5):575-579.

Sutureless Amniotic Membrane Transplantation in a Pediatric Patient with Acute Toxic Epidermal Necrolysis

The purpose of this case report is to describe a new surgical method for sutureless placement of the amniotic membrane with a symblepharon ring in a pediatric patient with acute toxic epidermal necrolysis (TEN). A 1-year-old girl developed severe ocular surface inflammation with large corneal and conjunctival epithelial defects secondary to TEN. She was treated by applying a large (4 cm x 4 cm) amniotic membrane graft and non-sterile symblepharon ring under sedoanalgesia at bedside in the intensive care unit. The ocular surface was completely epithelized by post-treatment week 6 in the right and week 8 in the left eye. Two years after amniotic membrane transplantation, both eyes were quiet with no symblepharon, scar formation, or limbal stem cell deficiency. Performing bilateral amniotic membrane transplantation under a symblepharon ring at bedside provided sufficient acute coverage of the ocular surface and led to excellent clinical outcomes by reducing inflammation and protecting the ocular surface.

Responsiveness to i.v. immunoglobulin therapy in patients with toxic epidermal necrolysis: A novel pharmaco-immunogenetic concept

Toxic epidermal necrolysis (TEN) represents a rare drug-induced autoimmune reaction with delayed-type hypersensitivity that initiates the process of developing massive keratinocyte apoptosis, dominantly in the dermoepidermal junction. Although the etiopathophysiology has not yet been fully elucidated, the binding of Fas ligand (FasL, CD95L) to the Fas receptor (CD95) was shown to play a key role in the induction of apoptosis in this syndrome. The knowledge of the role of immunoglobulin G (IgG) in inhibition of Fas-mediated apoptosis contributed to the introduction of i.v. Ig (IVIg) in the therapy of TEN patients. Despite great enthusiasm for this therapy at the end of the 1990s, subsequent studies in various populations and meta-analyses could not unequivocally confirm the efficacy of the IVIg-based treatment concept. Today, therefore, we are faced with the dilemmas of how to adjust therapy of TEN patients most effectively, which patients could benefit from IVIg therapy and what dose of the preparation should be administrated. The ground-breaking question is: do the host genetic profiles influence the responsiveness and side-effects of IVIg therapy in TEN patients? Based on recent pharmacological, immunological and genetic findings, we suggest that the variability of IVIg therapy outcomes in TEN patients may be related to functional variants in Fas, FasL and Fc-γ receptor genes. This novel concept could lead to improved quality of care for patients with TEN, facilitating personalized therapy to reduce mortality.

Recent advances in managing and understanding Stevens-Johnson syndrome and toxic epidermal necrolysis

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are life-threatening diseases characterized by detachment of the epidermis and mucous membrane. SJS/TEN are considered to be on the same spectrum of diseases with different severities. They are classified by the percentage of skin detachment area. SJS/TEN can also cause several complications in the liver, kidneys, and respiratory tract. The pathogenesis of SJS/TEN is still unclear. Although it is difficult to diagnose early stage SJS/TEN, biomarkers for diagnosis or severity prediction have not been well established. Furthermore, optimal therapeutic options for SJS/TEN are still controversial.

Several drugs, such as carbamazepine and allopurinol, are reported to have a strong relationship with a specific human leukocyte antigen (HLA) type. This relationship differs between different ethnicities. Recently, the usefulness of HLA screening before administering specific drugs to decrease the incidence of SJS/TEN has been investigated.

Skin detachment in SJS/TEN skin lesions is caused by extensive epidermal cell death, which has been considered to be apoptosis via the Fas-FasL pathway or perforin/granzyme pathway. We reported that necroptosis, i.e. programmed necrosis, also contributes to epidermal cell death. Annexin A1, released from monocytes, and its interaction with the formyl peptide receptor 1 induce necroptosis. Several diagnostic or prognostic biomarkers for SJS/TEN have been reported, such as CCL-27, IL-15, galectin-7, and RIP3.

Supportive care is recommended for the treatment of SJS/TEN. However, optimal therapeutic options such as systemic corticosteroids, intravenous immunoglobulin, cyclosporine, and TNF-α antagonists are still controversial. Recently, the beneficial effects of cyclosporine and TNF-α antagonists have been explored. In this review, we discuss recent advances in the pathophysiology and management of SJS/TEN.

Impact of mycoplasma pneumonia infection on urticaria: A nationwide, population-based retrospective cohort study in Taiwan

Mycoplasma pneumonia (MP) infection might be pathogenically closely related to urticaria. This study is a nationwide population-based cohort study from 1997 to 2013, which investigated the association between MP infection and urticaria in Taiwan. A total of 1,175 patients were included for the study group, and 2,350 for the control group. Multivariate Cox regression analysis was performed to estimate the adjusted hazard ratio (aHR) for urticaria. Result showed that 254 patients with new-onset urticaria were involved in the study group and 465 incident cases in the control group. The incidence rates (per 100,000 person-months) of urticaria were 37.2 and 32.5 in the study and control groups, respectively. The relative risk is 1.1 (95% CI = 1.0–1.3) indicating no significant correlation between MP and urticaria. The multivariate analysis revealed that the risk of urticaria with MP infection (aHR = 1.1, P = 0.1058) had no statistically significance difference compared to the control group. However, the risk of urticaria in MP-infected patients aged between 20 and 59 years old was found to have increased (aHR = 1.6, 95% CI = 1.1–2.2) prior to a diagnosis.

Serum and blister-fluid elevation and decreased epidermal content of high-mobility group box 1 protein in drug-induced Stevens-Johnson syndrome/toxic epidermal necrolysis

BACKGROUND

High-mobility group box 1 (HMGB1) is a damage-associated molecular-pattern protein. Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) are serious, immune-mediated skin-blistering conditions.

OBJECTIVES

To determine serum and/or blister-fluid total HMGB1 levels in SJS/TEN cohorts, and HMGB1 expression in formalin-fixed, paraffin-embedded (FFPE) SJS/TEN skin vs. healthy and maculopapular exanthema (MPE) skin. Methods Serum HMGB1 was quantified in Malawian nevirapine-induced hypersensitivity, Taiwanese SJS/TEN and Spanish SJS/TEN cohorts. FFPE skin (healthy skin, MPE, SJS/TEN) was stained and assessed for HMGB1 expression.

RESULTS

Serum total HMGB1 was not significantly elevated in patients with nevirapine-induced SJS/TEN (3·98 ± 2·17 ng mL^-1 ), MPE (3·92 ± 2·75 ng mL^-1 ) or drug reaction with eosinophilia and systemic symptoms (4·73 ± 3·00 ng mL^-1 ) vs. tolerant controls (2·97 ± 3·00 ng mL^-1 ). HMGB1 was significantly elevated in Taiwanese patients with SJS/TEN, highest during the acute phase (32·6 ± 26·6 ng mL^-1 ) vs. the maximal (19·7 ± 23·2 ng mL^-1 ; P = 0·007) and recovery (24·6 ± 25·3 ng mL^-1 ; P = 0·027) phases. In blister fluid from Spanish patients with SJS/TEN, HMGB1 (486·8 ± 687·9 ng mL^-1 ) was significantly higher than in serum (8·8 ± 7·6 ng mL^-1 ; P <0·001). Preblistered SJS/TEN skin showed decreased epidermal nuclear HMGB1 expression in upper epidermis vs. healthy or MPE skin but retained basal/suprabasal expression.

CONCLUSIONS

Epidermal HMGB1 expression was decreased in SJS/TEN skin. Retained basal/suprabasal epidermal HMGB1 expression may exacerbate localized injury in SJS/TEN.

A Review of the Pathogenesis of Toxic Epidermal Necrolysis

Toxic epidermal necrolysis (TEN) is a rare skin condition, most often drug-induced, known for its skin detachment and high mortality. In general, acute TEN is considered a T-cell mediated, type IV hypersensitivity disorder. It mostly results from a cumulative effect of risks from the drug structure, drug metabolism, HLA alleles and T cell clonotypes. However, the precise mechanism of TEN is still unknown. Apoptosis or necroptosis causes keratinocytes to lose their shape and adhesion, and necrosis predominates within a few days. Total epidermal necrosis separates the epidermis from the dermis. TEN is regarded as an immune reaction with predominantly CD8+ T lymphocytes, monocytes/macrophages, and natural killer cells. Impaired regulatory T-cells, T-helper 17 cells, cytotoxic granules such as perforin-granzyme and granulysin, tumor necrosis factor α, annexin, microRNA-18a-5p, and drug metabolites are all thought to be involved. From what is known, it can be assumed their mechanism is complex, and there is still much to be investigated. New findings will contribute to the identification of effective active methods of intervention.

Toxic epidermal necrolysis

Toxic epidermal necrolysis (TEN) is a rare, life-threatening drug-induced skin disease with a mortality rate of approximately 30%. The clinical hallmark of TEN is a marked skin detachment caused by extensive keratinocyte cell death associated with mucosal involvement. The exact pathogenic mechanism of TEN is still uncertain. Recent advances in this field have led to the identification of several factors that might contribute to the induction of excessive apoptosis of keratinocytes. In addition, specific human leukocyte antigen types seem to be associated with certain drugs and the development of TEN. As well-controlled studies are lacking, patients are treated with various immunomodulators (e.g. intravenous immunoglobulin) in addition to the best supportive care.

Variable levels of apoptotic signal-associated cytokines in the disease course of patients with Stevens-Johnson syndrome and toxic epidermal necrolysis

BACKGROUND/OBJECTIVES

Keratinocyte death is a hallmark of Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS/TEN). Apoptotic signal-associated cytokines, such as TNF-α, sFasL, granulysin, sTRAIL and IFN-γ have been reported to participate in keratinocyte apoptosis. However, their levels are variable, which hampers the elucidation of the role of these cytokines. We sought to determine whether cytokine levels vary with disease course.

METHODS

The serum cytokine levels of 24 patients and blister fluid of 10 were analysed by enzyme-linked immunosorbent assay on the first day of their admission to hospital and were evaluated at different time points in the disease course. Meanwhile, surface markers (CD3, CD4, CD8, CD1a, CD14, CD16+56 and CD68) of blister fluid cells were measured by flow cytometry.

RESULTS

The concentrations of all cytokines in the serum and blister fluid were higher than those in the controls and were more elevated in the blister fluid than in the serum. Moreover, sTRAIL, IFN-γ and TNF-α quantities were relatively stable, while those of sFasL and granulysin decreased rapidly in the disease course. On the first day, CD8+ T and natural killer cells were predominant in the blister fluid but their relative percentage diminished gradually, while that of CD14+ cells increased.

CONCLUSION

Our study confirmed there are high but variable levels of these cytokines in SJS/TEN, especially in the early phase and different tendencies are manifested in the disease course.