Immunohistochemical markers for histopathological diagnosis and differentiation of acute cutaneous graft-versus-host disease.

Graft-versus-host disease (GvHD) is a major complication following stem-cell or solid-organ transplantation. Accurate diagnosis of cutaneous GvHD is challenging, given that drug eruptions and viral rashes may present with similar clinical/histological manifestations. Specific markers are not available. We performed the histological examination of biopsy samples from acute GvHD (aGvHD; n = 54), Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN; n = 27), maculopapular drug eruption (MDE; n = 26) and healthy controls (n = 26). Samples of aGvHD showed a decrease in Langerhans cells (LC, p = 0.0001) and an increase in macrophages (MΦ, p = 0.0001) compared to healthy skin. Compared to SJS/TEN, MDE and healthy skin, aGvHD biopsies contained greater numbers of CD4+ and CD8+ T cells. The majority of CD4+ T-helper cells were localized in the upper dermis, whereas cytotoxic CD8+ T cells were found in the epidermis. Increased numbers of CD56+ natural killer (NK) cells in the upper dermis of aGvHD skin (p = 0.007) were not observed in controls or SJS/TEN and MDE. There were no differences in elafin staining between aGvHD and the latter two conditions. Acute GvHD appears to have a distinct inflammatory cell profile (T cells/NK cells) that may aid establishing in a more accurate diagnosis, especially when used to rule out differential diagnoses such as SJS/TEN or MDE.

T cell mediated hypersensitivity to previously tolerated iodinated contrast media precipitated by introduction of atezolizumab.

Many adverse reactions associated with immune checkpoint inhibitor (ICI) treatments are immunologically driven and may necessitate discontinuation of the ICI. Herein, we present a patient who had been administered the radio contrast media amidotrizoate multiple times without issue but who then developed a Stevens-Johnson syndrome reaction after coadministration of atezolizumab. Causality was confirmed by a positive re-challenge with amidotrizoate and laboratory investigations that implicated T cells. Importantly, the introduction of atezolizumab appears to have altered the immunologic response to amidotrizoate in terms of the tolerance-elicitation continuum. Proof of concept studies demonstrated enhancement of recall responses to a surrogate antigen panel following in-vitro (healthy donors) and in-vivo (ICI patients) administrations of ICIs. Our findings highlight the importance of considering all concomitant medications in patients on ICIs who develop immune-mediated adverse reactions. In the event of some immune-related adverse reactions, it may be critical to identify the culprit antigen-forming entity that the ICIs have altered the perception of rather than simply attribute causality to the ICI itself in order to optimize both patient safety and treatment of malignancies.

Carbamazepine Induces Focused T Cell Responses in Resolved Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis Cases But Does Not Perturb the Immunopeptidome for T Cell Recognition.

Antiseizure medications (ASMs) are frequently implicated in T cell-mediated drug hypersensitivity reactions and cause skin tropic pathologies that range in severity from mild rashes to life-threatening systemic syndromes. During the acute stages of the more severe manifestations of these reactions, drug responsive proinflammatory CD8+ T cells display classical features of Th1 cytokine production (e.g. IFNγ) and cytolysis (e.g. granzyme B, perforin). These T cells may be found locally at the site of pathology (e.g. blister cells/fluid), as well as systemically (e.g. blood, organs). What is less understood are the long-lived immunological effects of the memory T cell pool following T cell-mediated drug hypersensitivity reactions. In this study, we examine the ASM carbamazepine (CBZ) and the CBZ-reactive memory T cell pool in patients who have a history of either Stevens-Johnson syndrome (SJS) or toxic epidermal necrolysis (TEN) from 3-to-20 years following their initial adverse reaction. We show that in vitro drug restimulation of CBZ-reactive CD8+ T cells results in a proinflammatory profile and produces a mainly focused, yet private, T cell receptor (TCR) usage amongst human leukocyte antigen (HLA)-B*15:02-positive SJS or TEN patients. Additionally, we show that expression of these CBZ-reactive TCRs in a reporter cell line, lacking endogenous αßTCR, recapitulates the features of TCR activation reported for ASM-treated T cell lines/clones, providing a useful tool for further functional validations. Finally, we conduct a comprehensive evaluation of the HLA-B*15:02 immunopeptidome following ASM (or a metabolite) treatment of a HLA-B*15:02-positive B-lymphoblastoid cell line (C1R.B*15:02) and minor perturbation of the peptide repertoire. Collectively, this study shows that the CBZ-reactive T cells characterized require both the drug and HLA-B*15:02 for activation and that reactivation of memory T cells from blood results in a focused private TCR profile in patients with resolved disease.

Acute pancreatic injuries: A complication of Stevens-Johnson syndrome/toxic epidermal necrolysis associated with cytotoxic immunocell activation.

BACKGROUND: Complications involving internal organs are usually present in Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). However, pancreatic complications are rarely reported and studied. OBJECTIVE: To summarize clinical characteristics of SJS/TEN-associated acute pancreatic injuries and to investigate underlying inflammatory mechanisms. METHODS: Clinical records of 124 inpatients with SJS/TEN were reviewed. Serum levels of tumor necrosis factor α, interleukin (IL) 6, IL-18, IL-15, IL-12p70, and soluble CD56 were determined in 18 healthy donors and 17 patients with SJS/TEN, including 3 with acute pancreatic injuries. RESULTS: Acute pancreatic injury was diagnosed in 7.3% of patients (9/124) in the SJS/TEN cohort. Elevation of serum transaminase level and hypoalbuminemia occurred more frequently in patients with acute pancreatic injuries compared with those without pancreatic symptoms (P = .004 and <.001, respectively). Although acute pancreatic injury did not alter mortality rate of SJS/TEN, it was associated with longer hospitalization stays (P = .008). Within the serum cytokines whose levels were elevated in SJS/TEN, only IL-18 was found to be selectively increased in patients with acute pancreatic injuries compared with those without them (P = .03). LIMITATIONS: Cohort was small. CONCLUSION: Acute pancreatic injury is a gastrointestinal complication of SJS/TEN in which hepatotoxicity is more likely to occur. Overexpression of IL-18 might be involved in this unique entity.

Diagnosis and management of Stevens-Johnson syndrome/toxic epidermal necrolysis.

Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) is a rare, immunologically mediated cutaneous adverse reaction characterized by mucous membrane and epidermal detachment, with a mortality ranging from 15% to 25%. Risk factors for the development of SJS/TEN include immune dysregulation, active malignancy, and genetic predisposition. Medications are the most common cause, particularly antimicrobials, antiepileptics, allopurinol, and nonsteroidal anti-inflammatory medications. Drug-specific CD8 T-cells and natural killer cells are thought to be the major inducers of keratinocyte apoptosis via release of soluble cytotoxic mediators, including Fas ligand, perforin/granzyme, tumor necrosis factor, and granulysin. When SJS/TEN is suspected clinically, appropriate therapy should be instituted without delay. All patients should be managed initially in an intensive care unit or burn unit under a multidisciplinary team of physicians experienced in the care of patients with SJS/TEN. Available data support the use of various pharmacologic agents to halt disease progression and improve outcomes, but no single drug has been found to be superior or beneficial for all patients. Future research should focus on developing a better understanding of the genetic susceptibility and immunopathophysiology of the disease, as well as novel diagnostic and therapeutic targets to improve patient outcomes.

Cancer immunotherapy and toxic epidermal necrolysis.

OBJECTIVES: Immunotherapy has come to play an increasingly important role in cancer treatment. Accordingly, immune-related adverse events (irAEs) have drawn considerable attention. In this case, a young female patient developed immune-related toxic epidermal necrolysis (TEN). The same irAEs have been rarely reported in previous studies. In this study, we describe the treatment and care methods used in this case in detail in order to provide a reference for clinical practice. METHODS: After being diagnosed with TEN, the patient accepted systemic glucocorticoid therapy, timely care of skin and mucous membranes, nutrition support, antiacid therapy, anti-inflammatory, analgesics and other supportive measures. RESULTS: The patient's skin recovered completely, and no serious adverse outcomes, such as secondary infection or multiple organ failure, occurred during treatment. CONCLUSION: Medical staff should be able to identify the performance of rare irAEs such as TENs and actively explore comprehensive treatments to ensure patient safety and avoid adverse outcomes.

Stevens-Johnson syndrome and toxic epidermal necrolysis: risk factors, causality assessment and potential prevention strategies.

Introduction: The clinical manifestations of cutaneous adverse drug reactions are variable with different severity. Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are life-threatening severe cutaneous adverse reactions (SCARs) majorly caused by drugs and mediated by cytotoxic T cells.Areas covered: In this review, we focus on risk factors that contribute to the development of SJS/TEN and review the updated immune mechanism, preventive strategies as well as current therapeutic approaches for SJS/TEN.Expert opinion: The progress of SJS/TEN researches reveals that cytotoxic T cells majorly activated by drug interacted with the human leukocyte antigen (HLA) and T cell receptors play an important role for the immune mechanism of SJS/TEN. Several clinical assessment tools and in vitro drug-T cells activation tests have been developed to identify the causality of SJS/TEN. New therapeutic approaches and biologics such as TNF-alpha antagonist have been conducted to improve the prognosis of SJS/TEN.

Pharmacogenomics in Asian Subpopulations and Impacts on Commonly Prescribed Medications.

Asians as a group comprise > 60% the world's population. There is an incredible amount of diversity in Asian and admixed populations that has not been addressed in a pharmacogenetic context. The known pharmacogenetic differences in Asian subgroups generally represent previously known variants that are present at much lower or higher frequencies in Asians compared with other populations. In this review we summarize the main drugs and known genes that appear to have differences in their pharmacogenetic properties in certain Asian populations. Evidence-based guidelines and summary statistics from the US Food and Drug Administration and the Clinical Pharmacogenetics Implementation Consortium were analyzed for ethnic differences in outcomes. Implicated drugs included commonly prescribed drugs such as warfarin, clopidogrel, carbamazepine, and allopurinol. The majority of these associations are due to Asians more commonly being poor metabolizers of cytochrome P450 (CYP) 2C19 and carriers of the human leukocyte antigen (HLA)-B*15:02 allele. The relative risk increase was shown to vary between genes and drugs, but could be > 100-fold higher in Asians. Specifically, there was a 172-fold increased risk of Stevens-Johnson syndrome and toxic epidermal necrolysis with carbamazepine use among HLA-B*15:02 carriers. The effects ranged from relatively benign reactions such as reduced drug efficacy to severe cutaneous skin reactions. These reactions are severe and prevalent enough to warrant pharmacogenetic testing and appropriate changes in dose and medication choice for at-risk populations. Further studies should be done on Asian cohorts to more fully understand pharmacogenetic variants in these populations and to clarify how such differences may influence drug response.

Sulfonamide Hypersensitivity: Fact and Fiction.

Sulfonamide antimicrobials are commonly reported as causing drug allergy and have been implicated in a variety of hypersensitivity reactions including immediate IgE-mediated reactions, benign T-cell-mediated rashes, and severe cutaneous adverse reactions such as Stevens-Johnson syndrome, toxic epidermal necrolysis, and drug reaction with eosinophilia and systemic symptoms. Cross-reactivity is unlikely between sulfonamide antimicrobials and sulfonamide non-antimicrobials. In patients who develop reactions to a sulfonamide non-antimicrobial, there is no evidence to suggest that sulfonamide antimicrobials and other sulfonamide non-antimicrobials would cross-react. Although immediate skin testing can be performed in patients with histories of immediate reactions, they are infrequently positive and wane over time. Delayed skin testing including patch tests to sulfonamides is rarely positive. Drug challenges are a useful tool for patients with both immediate and delayed reactions to sulfonamides. The role of sulfamethoxazole desensitization is controversial as rates of hypersensitivity reactions are similar between desensitization and drug challenge.

Case of toxic epidermal necrolysis occurring after bone marrow transplantation accompanied by engraftment failure.

Toxic epidermal necrolysis (TEN) is a rare condition, causing life-threatening adverse cutaneous reactions. TEN occurrence after bone marrow transplantation (BMT) is a well-known phenomenon; however, to date, only a few cases have been reported in the published work. Here, we describe the case of a 53-year-old woman who experienced TEN after undergoing allogenic BMT for malignant lymphoma. Skin erosion spread across a maximum of 70% of the body surface area and severe mucosal lesions developed. Steroid pulse therapy, plasma apheresis and immunoglobulin therapy were administrated, which resulted in the complete resolution of TEN. However, she developed hemophagocytic lymphohistiocytosis and died 38 days after BMT, owing to rupture of the lower digestive tract complicated by multi-organ failure. In our case, engraftment failure occurred, and the peripheral white blood cell count was less than 100/µL during the TEN course, suggesting that the presence of only a few immune cells could cause TEN. Our findings showed that high mortality rates and widespread skin erosion could be regarded as the most important characteristics of TEN occurring after BMT.

Comprehensive assessment of T cell receptor ß repertoire in Stevens-Johnson syndrome/toxic epidermal necrolysis patients using high-throughput sequencing.

Stevens-Johnson syndrome (SJS) /toxic epidermal necrolysis (TEN) are life-threatening severe cutaneous adverse drug reactions characterized by widespread epidermal necrosis. Recent studies have indicated that SJS/TEN is a specific immune reaction regulated by T cells. Certain drug serves as foreign antigens that are presented by major histocompatibility complex (MHC) and recognized by T cell receptors (TCRs), inducing adaptive immune responses. However, few studies have performed detailed characterization of TCR repertoire in SJS/TEN, and it remains unclear whether the particular types of TCRs expanded clonally are drug-specific, which would provide a potential underlying mechanism of SJS/TEN. In this study, using high-throughput sequencing, we comprehensively assessed the diversity, composition and molecular characteristics of the TCRß repertoires in 17 SJS/TEN patients associated with three different causative drugs including methazolamide (MZ), carbamazepine (CBZ) and allopurinol (ALP). Systematic analysis of the TCRß sequences revealed that SJS/TEN patients had more highly expanded clones and less TCR repertoire diversity, and the TCR repertoire diversity of these patients showed certain associations with the clinical severity of disease. Similar predominant clonotypes, shared-usage TRBV/TRBJ subtypes and combinations thereof were observed among different subjects with the same causative agent. Our observations provide enhanced understanding of the role of T lymphocytes in the pathogenesis of SJS/TEN and enumerate potential therapeutic targets.

Cyclosporine for Epidermal Necrolysis: Absence of Beneficial Effect in a Retrospective Cohort of 174 Patients-Exposed/Unexposed and Propensity Score-Matched Analyses.

Cyclosporine has shown promising results for mortality in patients with Stevens-Johnson syndrome/toxic epidermal necrolysis. However, available studies included only a small number of patients and did not include a validated and homogenous control group. We present the results from a retrospective monocentric study including 174 patients with Stevens-Johnson syndrome/toxic epidermal necrolysis during 2005-2016. Among them, 95 received cyclosporine (3 mg/kg/day) plus supportive care, and 79 received supportive care only. Both a traditional exposed/unexposed method and a propensity score-matching method were used to compare the progression of skin detachment between day 0 and day 5, the proportion of patients with cutaneous re-epithelialization starting on day 5 or mucosal re-epithelialization on day 10, the duration of progression, and the number of deaths between the two groups. None of these outcomes significantly favored cyclosporine, either by the exposed/unexposed method or the propensity score method. Acute renal failure affected more patients receiving cyclosporine (P = 0.05). Overall, the results of this epidemiological study did not show a beneficial effect of cyclosporine in patients with Stevens-Johnson syndrome/toxic epidermal necrolysis. They are discordant with those previously published. The large number of patients and the use of a propensity score method provide valuable insights. The main limitation of the study is the lack of randomization.

Allopurinol suppresses expression of the regulatory T-cell migration factors TARC/CCL17 and MDC/CCL22 in HaCaT keratinocytes via restriction of nuclear factor-κB activation.

Recent studies have shown that sparse distribution of regulatory T cells (Tregs) in the skin might be involved in the onset of severe cutaneous adverse drug reactions such as Stevens-Johnson syndrome and toxic epidermal necrolysis. Treg migration toward epithelial cells is regulated by certain chemokines, including TARC/CCL17 and MDC/CCL22. In this study, we analyzed the effect of allopurinol (APN), a drug known to cause severe adverse reactions, on the expression of factors affecting Treg migration and the mechanisms involved. APN inhibited the tumor necrosis factor (TNF)-α- and interferon (IFN)-γ-associated expression of TARC/CCL17 and MDC/CCL22 mRNA in HaCaT cells in a dose-dependent manner. Consistent with this, APN also suppressed TNF-α- and IFN-γ-induced production of TARC/CCL17 and MDC/CCL22 proteins and the migration of C-C chemokine receptor type 4-positive cells. Activity of the transcription factors NF-κB and STAT1, which are involved in TARC/CCL17 and MDC/CCL22 expression, was also investigated. APN inhibited activation of NF-κB, but not that of STAT1. Furthermore, it restricted p38 MAPK phosphorylation. These results suggest that APN inhibits TNF-α- and IFN-γ-induced TARC/CCL17 and MDC/CCL22 production through downregulation of p38 MAPK and NF-κB signaling, resulting in the sparse distribution of Tregs in the skin of patients with APN-associated Stevens-Johnson syndrome/toxic epidermal necrolysis.

Diagnostic utility of HLA-B*5801 screening in severe allopurinol hypersensitivity syndrome: an updated systematic review and meta-analysis.

BACKGROUND: Despite many studies suggesting an association between human leukocyte antigen (HLA)-B*5801 and allopurinol-induced toxic epidermal necrolysis (TEN) and Stevens-Johnsons syndrome (SJS), the evidence of association in different populations and the degree of association remain uncertain. METHODS: The primary analysis was based on population-control studies. Data were pooled by means of a random-effects model, and sensitivity, specificity, positive likelihood ratios (LR+), negative likelihood ratios (LR-), diagnostic odds ratios (DOR), and areas under summary receiver operating characteristic (SROC) curves (AUC) were calculated. RESULTS: In nine population-control studies, HLA-B*5801 was measured in 162 patients with allopurinol-induced TEN/SJS and 7372 patients without allopurinol-induced TEN/SJS. The pooled sensitivity, specificity, LR+, LR-, DOR and AUC were 0.78 (95% CI = 0.71-0.85), 0.96 (95% CI = 0.96-0.97), 14.23 (95% CI = 7.89-25.63), 0.29 (95% CI = 0.16-0.54), 83.5 (95% CI = 50.7-137.4), and 0.97 (95% CI = 0.95-0.99), respectively. Subgroup analyses of the DORs for Chinese, Japanese, and Caucasian populations yielded similar findings for Chinese (196.1; 95% CI = 57.3-672.0), Japanese (78.8; 95% CI = 30.4-203.9), and Caucasian (58.4; 95% CI = 16.9-201.5) populations. Overall, HLA-B*5801 was associated with allopurinol-induced TEN/SJS in European and Japanese populations, but only had a 50-60% sensitivity (pooled sensitivity 56%), compared to the 80-100% sensitivity (pooled sensitivity 97%) observed in Korean, Thai, Sardinia Italian and Han Chinese populations. CONCLUSIONS: The present study reveals that allopurinol is the leading cause of TEN/SJS in many countries. In contrast to carbamazepine, which is ethnic/population specific, the HLA-B*5801 for detecting allopurinol-induced TEN/SJS is universal. Screening of HLA-B*5801 may help patients to prevent the occurrence of allopurinol-induced TEN/SJS, especially in populations with a higher (≥ 5%) risk allele frequency.

Systemic Immunomodulating Therapies for Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis: A Systematic Review and Meta-analysis.

Importance: Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS/TEN) are rare but severe adverse reactions with high mortality. There is no evidence-based treatment, but various systemic immunomodulating therapies are used. Objectives: To provide an overview on possible immunomodulating treatments for SJS/TEN and estimate their effects on mortality compared with supportive care. Data Sources: A literature search was performed in December 2012 for articles published in MEDLINE, MEDLINE Daily, MEDLINE Inprocess, Web of Science, EMBASE, Scopus, and the Cochrane Library (Central) from January 1990 through December 2012, and updated in December 2015, in the English, French, Spanish, and German languages looking for treatment proposals for SJS/TEN. Other sources were screened manually. Study Selection: Initially, 157 randomized and nonrandomized studies on therapies (systemic immunomodulating therapies or supportive care) for SJS/TEN were selected. Data Extraction and Synthesis: Relevant data were extracted from articles. Authors were contacted for further information. Finally, 96 studies with sufficient information regarding eligibility and adequate quality scores were considered in the data synthesis. All steps were performed independently by 2 investigators. Meta-analyses on aggregated study data (random-effects model) and individual patient data (IPD) (logistic regression adjusted for confounders) were performed to assess therapeutic efficacy. In the analysis of IPD, 2 regression models, stratified and unstratified by study, were fitted. Main Outcomes and Measures: Therapy effects on mortality were expressed in terms of odds ratios (ORs) with 95% CIs. Results: Overall, 96 studies (3248 patients) were included. Applied therapies were supportive care or systemic immunomodulating therapies, including glucocorticosteroids, intravenous immunoglobulins, cyclosporine, plasmapheresis, thalidomide, cyclophosphamide, hemoperfusion, tumor necrosis factor inhibitors, and granulocyte colony-stimulating factors. Glucocorticosteroids were associated with a survival benefit for patients in all 3 analyses but were statistically significant in only one (aggregated data: OR, 0.5; 95%% CI, 0.3-1.01; IPD, unstratified: OR, 0.7; 95% CI, 0.5-0.97; IPD, stratified: OR, 0.8; 95% CI, 0.4-1.3). Despite the low patient size, cyclosporine was associated with a promising significant result in the only feasible analysis of IPD (unstratified model) (OR, 0.1; 95% CI, 0.0-0.4). No beneficial findings were observed for other therapies, including intravenous immunoglobulins. Conclusions and Relevance: Although all analyses, including the unstratified model, had limitations, glucocorticosteroids and cyclosporine were the most promising systemic immunomodulating therapies for SJS/TEN. Further evaluation in prospective studies is required. However, this work provides a comprehensive overview on proposed systemic immunomodulating treatments for SJS/TEN, which is of great relevance for treating physicians.