Recent progress of Stevens-Johnson syndrome/toxic epidermal necrolysis: Diagnosis criteria, pathogenesis and therapy.

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) represent a severe spectrum of rare mucocutaneous reactions, primarily drug-induced and characterized by significant morbidity and mortality. These conditions manifest through extensive skin detachment, distinguishing them from other generalized skin eruptions. The rarity and severity of SJS/TEN underscore the importance of accurate diagnostic criteria and effective treatments, which are currently lacking consensus. This review proposes new diagnostic criteria to improve specificity and global applicability. Recent advancements in understanding the immunopathogenesis of SJS/TEN are explored, emphasizing the role of drug-specific T cell responses and HLA polymorphisms in disease onset. The review also addresses current therapeutic approaches, including controversies surrounding the use of immunosuppressive agents and the emerging role of TNF-α inhibitors. Novel therapeutic strategies targeting specific pathogenic mechanisms, such as necroptosis and specific immune cell pathways, are discussed. Furthermore, the development of new drugs based on these insights, including targeted monoclonal antibodies and inhibitors, are examined. The review concludes by advocating for more robust and coordinated efforts across multidisciplinary medical fields to develop effective treatments and diagnostic tools for SJS/TEN, with the aim of improving patient outcomes and understanding of the disease and its mechanisms.

Levels of environmental contamination with SARS-CoV-2 in hospital rooms and salivary viral loads of patients with coronavirus disease 2019.

BACKGROUND: Clarifying the presence of viable severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) rather than SARS-CoV-2 viral RNA in inpatient rooms is important for infection control of coronavirus disease 2019 (COVID-19). In this study, we investigated levels of viral RNA and viable virus on environmental surfaces and in patient saliva. METHODS: Environmental samples from 23 sites in hospital rooms were collected every other day until patient discharge. Saliva specimens and samples from the inner surface of patient masks were also collected. Additionally, environmental samples were collected from 46 sites in hospital rooms on discharge day. The samples were examined using quantitative reverse transcription polymerase chain reaction (RT-qPCR) and plaque assays. RESULTS: The 10 enrolled cases were classified as mild COVID-19, and patients were discharged after 6-9 days. The viral RNA was detected in 12.4% (105/849) of serially collected environmental samples during hospitalization, whereas viable virus was detected only in 0.47% (4/849), which were from sinks and tap levers. Although all patients recovered, three cases retained viable virus in the last saliva specimen collected. In the 15 discharged rooms, viral RNA was detected in 6.6% (45/682) of the samples, and viable virus was detected in only one sample from the sink. CONCLUSIONS: Although environmental surfaces surrounding patients with COVID-19 were frequently contaminated with viral RNA, the presence of viable virus was rare and limited only to areas around sinks. These results suggest that contact infection risk via fomites in hospital rooms is extremely rare.

Assessment of environmental surface contamination with SARS-CoV-2 in concert halls and banquet rooms in Japan.

BACKGROUND: Although crowds are considered to be a risk factor for SARS-CoV-2 transmission, little is known about the changes in environmental surface contamination with the virus when a large number of people attend an event. In this study, we evaluated the changes in environmental surface contamination with SARS-CoV-2. METHODS: Environmental samples were collected from concert halls and banquet rooms before and after events in February to April 2022 when the 7-day moving average of new COVID-19 cases in Tokyo was reported to be 5000-18000 cases per day. In total, 632 samples were examined for SARS-CoV-2 by quantitative reverse transcription polymerase chain reaction (RT-qPCR) tests, and RT-qPCR-positive samples were subjected to a plaque assay. RESULTS: The SARS-CoV-2 RNA detection rate before and after the events ranged from 0% to 2.6% versus 0%-5.0% in environmental surface samples, respectively. However, no viable viruses were isolated from all RT-qPCR-positive samples by the plaque assay. There was no significant increase in the environmental surface contamination with SARS-CoV-2 after these events. CONCLUSIONS: These findings revealed that indirect contact transmission from environmental fomite does not seem to be of great magnitude in a community setting.

Drug allergy and autoimmune diseases.

Systemic autoimmune diseases are reportedly associated with a high frequency of drug allergies. In particular, systemic lupus erythematosus (SLE), Sjögren's syndrome (SS), and adult-onset Still's disease (AOSD) have recently drawn attention. Based on previous reports, drug allergies have been reported in 17.1-63%, 7-40.1%, and 17.6-54% of patients with SS, SLE, and AOSD patients, respectively. Antimicrobial agents, including sulfa drugs and nonsteroidal anti-inflammatory drugs, are the most common causative agents of drug allergies. However, few studies have examined in detail the relationship between drug eruptions, a major symptom of drug allergy, and systemic autoimmune diseases, and their actual status remains unclear. These autoimmune diseases commonly exhibit a diverse range of skin manifestations in the course of these diseases, rendering it may be difficult to determine whether it is a true drug eruption. Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN), a fatal, severe drug eruption, has also been associated with autoimmune diseases. The development of SS-like symptoms after SJS/TEN onset and high prevalence of anti-SS-A antibodies in SJS/TEN are intriguing observations. Although the presence of SLE is known to be a risk factor for SJS/TEN, common pathological conditions, such as excessive immune status, abnormal function of regulatory T cells, and neutrophil extracellular traps in autoimmune diseases such as SS and SLE, are potentially involved in the development of drug eruptions.

Pathogenic UBA1 variants associated with VEXAS syndrome in Japanese patients with relapsing polychondritis.

OBJECTIVES: To determine clinical and genetic features of individuals with relapsing polychondritis (RP) likely caused by pathogenic somatic variants in ubiquitin-like modifier activating enzyme 1 (UBA1). METHODS: Fourteen patients with RP who met the Damiani and Levine criteria were recruited (12 men, 2 women; median onset age (IQR) 72.1 years (67.1-78.0)). Sanger sequencing of UBA1 was performed using genomic DNA from peripheral blood leukocytes or bone marrow tissue. Droplet digital PCR (ddPCR) and peptide nucleic acid (PNA)-clamping PCR were used to detect low-prevalence somatic variants. Clinical features of the patients were investigated retrospectively. RESULTS: UBA1 was examined in 13 of the 14 patients; 73% (8/11) of the male patients had somatic UBA1 variants (c.121A>C, c.121A>G or c.122T>C resulting in p.Met41Leu, p.Met41Val or p.Met41Thr, respectively). All the variant-positive patients had systemic symptoms, including a significantly high prevalence of skin lesions. ddPCR detected low prevalence (0.14%) of somatic variant (c.121A>C) in one female patient, which was subsequently confirmed by PNA-clamping PCR. CONCLUSIONS: Genetic screening for pathogenic UBA1 variants should be considered in patients with RP, especially male patients with skin lesions. The somatic variant in UBA1 in the female patient is the first to be reported.

Mortality and risk factors on admission in toxic epidermal necrolysis: A cohort study of 59 patients.

BACKGROUND: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare but life-threatening disorders characterized by widespread epidermal necrosis of the skin and mucosa. The severity-of-illness scoring system for TEN (SCORTEN) was widely used since 2000 as a standard prognostic tool consisting of seven clinical values. METHODS: To evaluate the prognosis using current treatments and risk factors for mortality, we retrospectively analyzed 59 cases of TEN, including SJS/TEN overlap treated in two university hospitals from January 2000 to March 2020. RESULTS: The mortality rate of TEN was 13.6% (8/59). All patients treated with high-dose steroid administration in combination with plasma exchange and/or immunoglobulin therapy recovered. Logistic regression analysis showed nine clinical composite scores, namely: heart rate (≧120 bpm), malignancy present, percentage of body surface area with epidermal detachment (>10%), blood urea nitrogen (>28 mg/dL), serum bicarbonate level (<20 mEq/L), serum glucose level (>252 mg/dL), age (≧71 years), the interval between disease onset and treatment initiation at the specialty hospital (≧8 days), and respiratory disorder within 48 h after admission. The receiver operating characteristic curves confirmed a high potential for predicting the prognosis of TEN. CONCLUSIONS: Recent developments in treatment strategies have contributed to the improved prognosis of TEN patients. A modified severity scoring model composed of nine scores may be helpful in the prediction of TEN prognosis in recent patients. Further large-scale studies are needed to confirm mortality findings to improve prognostication in patients with TEN.

Cross-Talk between Transforming Growth Factor-ß and Periostin Can Be Targeted for Pulmonary Fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a devastating disease characterized as progressive and irreversible fibrosis in the interstitium of lung tissues. There is still an unmet need to develop a novel therapeutic drug for IPF. We have previously demonstrated that periostin, a matricellular protein, plays an important role in the pathogenesis of pulmonary fibrosis. However, the underlying mechanism of how periostin causes pulmonary fibrosis remains unclear. In this study, we sought to learn whether the cross-talk between TGF-ß (transforming growth factor-ß), a central mediator in pulmonary fibrosis, and periostin in lung fibroblasts leads to generation of pulmonary fibrosis and whether inhibitors for integrin αVß3, a periostin receptor, can block pulmonary fibrosis in model mice and the TGF-ß signals in fibroblasts from patients with IPF. We found that cross-talk exists between TGF-ß and periostin signals via αVß3/ß5 converging into Smad3. This cross-talk is necessary for the expression of TGF-ß downstream effector molecules important for pulmonary fibrosis. Moreover, we identified several potent integrin low-molecular-weight inhibitors capable of blocking cross-talk with TGF-ß signaling. One of the compounds, CP4715, attenuated bleomycin-induced pulmonary fibrosis in vivo in mice and the TGF-ß signals in vitro in fibroblasts from patients with IPF. These results suggest that the cross-talk between TGF-ß and periostin can be targeted for pulmonary fibrosis and that CP4715 can be a potential therapeutic agent to block this cross-talk.

Clinical characteristics of cancer-associated myositis complicated by interstitial lung disease: a large-scale multicentre cohort study.

OBJECTIVE: To clarify the incidence, risk factors, and impact of malignancy in patients with PM/DM-associated interstitial lung disease (ILD). METHODS: This study used data from 497 patients with PM/DM-associated ILD enrolled in a multicentre, retrospective and prospective cohort of incident cases. Cancer-associated myositis (CAM) was defined as malignancy diagnosed within 3 years before or after PM/DM diagnosis. Demographic and clinical information was recorded at the time of diagnosis, and data about the occurrence of mortality and malignancy was collected. RESULTS: CAM was identified in 32 patients with PM/DM-associated ILD (6.4%). Patients with CAM were older (64 vs 55 years, P < 0.001), presented with arthritis less frequently (24% vs 49%, P = 0.01), and showed a lower level of serum Krebs von den Lungen-6 (687 vs 820 IU/l, P = 0.03) than those without CAM. The distribution of myositis-specific autoantibodies, including anti-melanoma differentiation-associated gene 5, anti-aminoacyl tRNA synthetase, and anti-transcriptional intermediary factor 1-γ antibodies, did not differ between the groups. Survival analysis demonstrated that CAM patients had a poorer survival than non-CAM patients (P = 0.006), primarily due to excess deaths by concomitant malignancy, while mortality due to ILD-related respiratory failure was similar between the groups (P = 0.51). CONCLUSION: Concomitant malignancy can occur in patients with PM/DM-associated ILD, and has significant impact on mortality. Older age, lack of arthritis, and a lower level of serum Krebs von den Lungen-6 at diagnosis are predictors of concomitant malignancy.

Periostin plays a critical role in the cell cycle in lung fibroblasts.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a devastating disease with a median survival of only three to 5 years. Fibroblast proliferation is a hallmark of IPF as is secretion of extracellular matrix proteins from fibroblasts. However, it is still uncertain how IPF fibroblasts acquire the ability to progressively proliferate. Periostin is a matricellular protein highly expressed in the lung tissues of IPF patients, playing a critical role in the pathogenesis of pulmonary fibrosis. However, it remains undetermined whether periostin affects lung fibroblast proliferation. METHODS: In this study, we first aimed at identifying periostin-dependently expressed genes in lung fibroblasts using DNA microarrays. We then examined whether expression of cyclins and CDKs controlling cell cycle progression occur in a periostin-dependent manner. We next examined whether downregulation of cell proliferation-promoting genes by knockdown of periostin or integrin, a periostin receptor, using siRNA, is reflected in the cell proliferation of lung fibroblasts. We then looked at whether lung fibroblasts derived from IPF patients also require periostin for maximum proliferation. We finally investigated whether CP4715, a potent inhibitor against integrin αVß3 (a periostin receptor), which we have recently found blocks TGF-ß signaling, followed by reduced BLM-induced pulmonary fibrosis in mice, can block proliferation of lung fibroblasts derived from IPF patients. RESULTS: Many cell-cycle-related genes are involved in the upregulated or downregulated genes by periostin knockdown. We confirmed that in lung fibroblasts, periostin silencing downregulates expression of several cell-cycle-related molecules, including the cyclin, CDK, and, E2F families, as well as transcription factors such as B-MYB and FOXM1. Periostin or integrin silencing slowed proliferation of lung fibroblasts and periostin silencing increased the distribution of the G0/G1 phase, whereas the distribution of the G2/M phase was decreased. Lung fibroblasts derived from IPF patients also required periostin for maximum proliferation. Moreover, CP4715 downregulated proliferation along with expression of cell-cycle-related genes in IPF lung fibroblasts as well as in normal lung fibroblasts. CONCLUSIONS: Periostin plays a critical role in the proliferation of lung fibroblasts and the present results provide us a solid basis for considering inhibitors of the periostin/integrin αVß3 interaction for the treatment of IPF patients.

Systemic Dermatitis Model Mice Exhibit Atrophy of Visceral Adipose Tissue and Increase Stromal Cells via Skin-Derived Inflammatory Cytokines.

: Adipose tissue (AT) is the largest endocrine organ, producing bioactive products called adipocytokines, which regulate several metabolic pathways, especially in inflammatory conditions. On the other hand, there is evidence that chronic inflammatory skin disease is closely associated with vascular sclerotic changes, cardiomegaly, and severe systemic amyloidosis in multiple organs. In psoriasis, a common chronic intractable inflammatory skin disease, several studies have shown that adipokine levels are associated with disease severity. Chronic skin disease is also associated with metabolic syndrome, including abnormal tissue remodeling; however, the mechanism is still unclear. We addressed this problem using keratin 14-specific caspase-1 overexpressing transgenic (KCASP1Tg) mice with severe erosive dermatitis from 8 weeks of age, followed by re-epithelization. The whole body and gonadal white AT (GWAT) weights were decreased. Each adipocyte was large in number, small in size and irregularly shaped; abundant inflammatory cells, including activated CD4+ or CD8+ T cells and toll-like receptor 4/CD11b-positive activated monocytes, infiltrated into the GWAT. We assumed that inflammatory cytokine production in skin lesions was the key factor for this lymphocyte/monocyte activation and AT dysregulation. We tested our hypothesis that the AT in a mouse dermatitis model shows an impaired thermogenesis ability due to systemic inflammation. After exposure to 4 °C, the mRNA expression of the thermogenic gene uncoupling protein 1 in adipocytes was elevated; however, the body temperature of the KCASP1Tg mice decreased rapidly, revealing an impaired thermogenesis ability of the AT due to atrophy. Tumor necrosis factor (TNF)-α, IL-1ß and interferon (INF)-γ levels were significantly increased in KCASP1Tg mouse ear skin lesions. To investigate the direct effects of these cytokines, BL/6 wild mice were administered intraperitoneal TNF-α, IL-1ß and INF-γ injections, which resulted in small adipocytes with abundant stromal cell infiltration, suggesting those cytokines have a synergistic effect on adipocytes. The systemic dermatitis model mice showed atrophy of AT and increased stromal cells. These findings were reproducible by the intraperitoneal administration of inflammatory cytokines whose production was increased in inflamed skin lesions.

Cerebellar ataxia-dominant phenotype in patients with ERCC4 mutations.

Autosomal recessive cerebellar ataxias (ARCAs) are clinically and genetically heterogeneous neurological disorders. Through whole-exome sequencing of Japanese ARCA patients, we identified three index patients from unrelated families who had biallelic mutations in ERCC4. ERCC4 mutations have been known to cause xeroderma pigmentosum complementation group F (XP-F), Cockayne syndrome, and Fanconi anemia phenotypes. All of the patients described here showed very slowly progressive cerebellar ataxia and cognitive decline with choreiform involuntary movement, with young adolescent or midlife onset. Brain MRI demonstrated atrophy that included the cerebellum and brainstem. Of note, cutaneous symptoms were very mild: there was normal to very mild pigmentation of exposed skin areas and/or an equivocal history of pathological sunburn. However, an unscheduled DNA synthesis assay of fibroblasts from the patient revealed impairment of nucleotide excision repair. A similar phenotype was very recently recognized through genetic analysis of Caucasian cerebellar ataxia patients. Our results confirm that biallelic ERCC4 mutations cause a cerebellar ataxia-dominant phenotype with mild cutaneous symptoms, possibly accounting for a high proportion of the genetic causes of ARCA in Japan, where XP-F is prevalent.

Squamous Cell Carcinoma Antigen 2 (SCCA2, SERPINB4): An Emerging Biomarker for Skin Inflammatory Diseases.

Squamous cell carcinoma antigens 1 and 2 (SCCA1 and 2, SERPIN B3 and B4), members of the ovalbumin serpin (ov-serpin)/clade B serpin family, were originally discovered as tumor-specific antigens and are used as tumor markers for various kinds of squamous cell carcinomas. Recently, our understanding of the underlying mechanisms of how SCCA1/2 enhance tumor growth has greatly increased. Moreover, it has been shown that SCCA1/2 are involved in the pathogenesis of several inflammatory diseases: asthma, psoriasis, and atopic dermatitis (AD). IL-22 and IL-17, signature cytokines of type 17 inflammation, as well as IL-4 and IL-13, signature cytokines of type 2 inflammation, both of which are positively correlated with the pathogenesis of psoriasis and allergic diseases, respectively, can induce expression of SCCA1/2 in airway epithelial cells and/or keratinocytes, leading to high expression of SCCA1/2 in these diseases. Based on these findings, several trials have been performed to examine the potential of applying SCCA1/2 to biomarkers for these diseases. The findings show that SCCA2 is useful to aid diagnosis, estimate clinical severity and disease type, and assess responses to treatment in psoriasis and AD. These results suggest that SCCA2 has emerged as a novel biomarker for skin inflammatory diseases.

Serum levels of squamous cell carcinoma antigens 1 and 2 reflect disease severity and clinical type of atopic dermatitis in adult patients.

BACKGROUND: Recent studies have indicated that serum levels of squamous cell carcinoma antigen (SCCA) 1 and 2 induced by type 2 cytokines such as IL-4 and IL-13, are increased in patients with atopic dermatitis (AD). However, no clinical studies have analyzed serum levels of SCCA2 in larger series of AD patients or their association with various clinical characteristics. This study was performed to clarify whether serum levels of SCCA2 are associated with disease severity and clinical phenotypes of adult AD patients. METHODS: An enzyme-linked immunosorbent assay was performed to examine serum SCCA2 levels in 240 adult patients with AD and 25 healthy controls in this study. Serum SCCA2 levels were analyzed with clinical characteristics and laboratory parameters including thymus and activation-regulated chemokine (TARC), lactate dehydrogenase (LDH), blood eosinophils, total IgE, and specific IgE (Japanese cedar pollen, Dermatophagoides farina, Candida, malassezia, Staphylococcal enterotoxin B). Expression of SCCA2 in AD eruption was examined by immunohistochemistry. The effect of treatment on serum SCCA2 was also assessed. RESULTS: Serum SCCA2 level showed a positive correlation with disease severity, levels of TARC, LDH, eosinophil counts, and IgE levels. Robust expression of SCCA2 was detected in the supra basal keratinocytes in the epidermis of AD patients. Serial measurements of serum SCCA2 revealed decreased levels of SCCA2 after treatment for AD. CONCLUSIONS: Serum SCCA2 levels reflected disease severity and clinical type of AD. Serum SCCA2 may thus be a relevant biomarker for AD.

Retrospective analysis of Stevens-Johnson syndrome and toxic epidermal necrolysis in 87 Japanese patients--Treatment and outcome.

BACKGROUND: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare but severe adverse drug reactions with high mortality. METHODS: To present the clinical characteristics of SJS and TEN in Japan and evaluate the efficacy of treatments, we retrospectively analyzed cases of SJS and TEN treated in 2 university hospitals during 2000-2013. RESULTS: Fifty-two cases of SJS (21 males and 31 females; average age, 55.1 years) and 35 cases of TEN (17 males and 18 females; average age, 56.6 years) were included in this study. Twenty-eight cases of SJS (53.8%) and all cases of TEN were caused by drugs. Hepatitis was the most common organ involvement in both SJS and TEN. Renal dysfunction, intestinal disorder, and respiratory disorder were also involved in some cases. The major complication was pneumonia and sepsis. All cases except for 3 cases were treated systemically with corticosteroids. Steroid pulse therapy was performed in 88.6% of TEN. Plasmapheresis and/or immunoglobulin therapy was combined with steroid therapy mainly in TEN after 2007. The mortality rate was 6.9% and the rates for SJS and TEN were 1.9% and 14.3%, respectively. These were much lower than predicted mortality according to a severity-of-illness scoring system for TEN prognosis (SCORTEN) score. When comparing the mortality rate between 2000-2006 and 2007-2013, it was decreased from 4.5% to 0.0% in SJS and from 22.2% to 5.3% in TEN. CONCLUSIONS: Treatment with steroid pulse therapy in combination with plasmapheresis and/or immunoglobulin therapy seems to have contributed to prognostic improvement in SJS/TEN.

Genetic and biological characterization of Muko virus, a new distinct member of the species Great Island virus (genus Orbivirus, family Reoviridae), isolated from ixodid ticks in Japan.

Among the tick-borne orbiviruses (genus Orbivirus, family Reoviridae), 36 serotypes are currently classified within a single virus species, Great Island virus. In this study, we report the first characterization of a tick-borne orbivirus isolated from the tick Ixodes turdus in Japan, which we identified as a new member of the species Great Island virus. The virus isolate, designated Muko virus (MUV), replicated and induced cytopathic effects in BHK-21, Vero E6, and CCL-141 cells and caused high mortality in suckling mice after intracerebral inoculation. Full genome sequence analysis showed that MUV shared the greatest phylogenetic similarity with Tribec virus in terms of the amino acid sequences of all viral proteins except for outer capsid protein 1 (OC1; VP4 of MUV). Analysis of genome segment 9 in MUV detected an uninterrupted open reading frame that overlaps with VP6 (Hel), which putatively encodes a molecular and functional equivalent of NS4 from Great Island virus. Our study provides new insights into the geographic distribution, genetic diversity, and evolutionary history of the members of the species Great Island virus.

Periostin contributes to epidermal hyperplasia in psoriasis common to atopic dermatitis.

BACKGROUND: Epidermal hyperplasia is a histological hallmark observed in both atopic dermatitis (AD) and psoriasis, although the clinical features and the underlying immunological disorders of these diseases are different. We previously showed that periostin, a matricellular protein, plays a critical role in epidermal hyperplasia in AD, using a mouse model and a 3-dimensional organotypic coculture system. In this study, we explore the hypothesis that periostin is involved in epidermal hyperplasia in psoriasis. METHODS: To examine expression of periostin in psoriasis patients, we performed immunohistochemical analysis on skin biopsies from six such patients. To investigate periostin's role in the pathogenesis of psoriasis, we evaluated periostin-deficient mice in a psoriasis mouse model induced by topical treatment with imiquimod (IMQ). RESULTS: Periostin was substantially expressed in the dermis of all investigated psoriasis patients. Epidermal hyperplasia induced by IMQ treatment was impaired in periostin-deficient mice, along with decreased skin swelling. However, upon treatment with IMQ, periostin deficiency did not alter infiltration of inflammatory cells such as neutrophils; production of IL-17, -22, or -23; or induction/expansion of IL-17- and IL-22-producing group 3 innate lymphoid cells. CONCLUSIONS: Periostin plays an important role during epidermal hyperplasia in IMQ-induced skin inflammation, independently of the IL-23-IL-17/IL-22 axis. Periostin appears to be a mediator for epidermal hyperplasia that is common to AD and psoriasis.