S2k guidelines on diagnosis and treatment of linear IgA dermatosis initiated by the European Academy of Dermatology and Venereology.

INTRODUCTION: Linear IgA dermatosis (LAD) is a rare subepidermal autoimmune bullous disease (AIBD) defined by predominant or exclusive immune deposits of immunoglobulin A at the basement membrane zone of skin or mucous membranes. This disorder is a rare, clinically and immunologically heterogeneous disease occurring both in children and in adults. The aim of this project is to present the main clinical features of LAD, to propose a diagnostic algorithm and provide management guidelines based primarily on experts' opinion because of the lack of large methodologically sound clinical studies. METHODS: These guidelines were initiated by the European Academy of Dermatology and Venereology (EADV) Task Force Autoimmune Bullous Diseases (AIBD). To achieve a broad consensus for these S2k consensus-based guidelines, a total of 29 experts from different countries, both European and non-European, including dermatologists, paediatric dermatologists and paediatricians were invited. All members of the guidelines committee agreed to develop consensus-based (S2k) guidelines. Prior to a first virtual consensus meeting, each of the invited authors elaborated a section of the present guidelines focusing on a selected topic, based on the relevant literature. All drafts were circulated among members of the writing group, and recommendations were discussed and voted during two hybrid consensus meetings. RESULTS: The guidelines summarizes evidence-based and expert opinion-based recommendations (S2 level) on the diagnosis and treatment of LAD. CONCLUSION: These guidelines will support dermatologists to improve their knowledge on the diagnosis and management of LAD.

Recrudescence of Severe Carbamazepine- Induced DRESS Syndrome after Initiation of Levetiracetam.

Drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome is a potentially fatal cutaneous hypersensitivity reaction commonly precipitated by antiepileptic drugs (AEDs). Cross-reactivity among aromatic AEDs is well-documented, but between aromatic and nonaromatic AEDs. We report a patient with severe DRESS syndrome precipitated by aromatic AED carbamazepine with recrudescence approximately 2 weeks after substitution with nonaromatic AED levetiracetam. The patient was treated with high-dose corticosteroids and switched to the benzodiazepine AED clobazam. At follow-up appointment several weeks later, the patient's rash, liver injury, and eosinophilia had resolved.

Single-cell landscape analysis unravels molecular programming of the human B cell compartment in chronic GVHD.

Alloreactivity can drive autoimmune syndromes. After allogeneic hematopoietic stem cell transplantation (allo-HCT), chronic graft-versus-host disease (cGVHD), a B cell-associated autoimmune-like syndrome, commonly occurs. Because donor-derived B cells continually develop under selective pressure from host alloantigens, aberrant B cell receptor (BCR) activation and IgG production can emerge and contribute to cGVHD pathobiology. To better understand molecular programing of B cells in allo-HCT, we performed scRNA-Seq analysis on high numbers of purified B cells from patients. An unsupervised analysis revealed 10 clusters, distinguishable by signature genes for maturation, activation, and memory. Within the memory B cell compartment, we found striking transcriptional differences in allo-HCT patients compared with healthy or infected individuals, including potentially pathogenic atypical B cells (ABCs) that were expanded in active cGVHD. To identify intrinsic alterations in potentially pathological B cells, we interrogated all clusters for differentially expressed genes (DEGs) in active cGVHD versus patients who never had signs of immune tolerance loss (no cGVHD). Active cGVHD DEGs occurred in both naive and BCR-activated B cell clusters. Remarkably, some DEGs occurred across most clusters, suggesting common molecular programs that may promote B cell plasticity. Our study of human allo-HCT and cGVHD provides understanding of altered B cell memory during chronic alloantigen stimulation.

Detection of novel therapies using a multi-national, multi-institutional registry of cutaneous immune-related adverse events and management.

BACKGROUND: Cutaneous immune-related adverse events (cirAEs) remain a prevalent and common sequelae of immune checkpoint inhibitor (ICI) therapy, often necessitating treatment interruption and prolonged immune suppression. Treatment algorithms are still poorly defined, based on single-institution case reports without adequate safety assessments, and subject to publication bias. METHODS: Data in this registry were collected through a standardized REDCap form distributed to dermatologists via email listserv. RESULTS: Ninety-seven cirAEs were reported from 13 institutions in this registry. Topical and systemic steroids were the most common treatments used; however, targeted treatment matched to disease morphology was identified at numerous sites. Novel cirAE therapy uses that to our knowledge have not been previously described were captured including tacrolimus for the treatment of follicular, bullous, and eczematous eruptions and phototherapy for eczematous eruptions. Moreover, further evidence of cirAE treatment applications sparsely described in literature were also captured in this study including dupilumab and rituximab for bullous eruptions, phototherapy for lichenoid and psoriasiform eruptions, and acitretin for psoriasiform eruptions, among others. No serious adverse events were reported. Numerous targeted therapeutics including dupilumab, rituximab, and psoriasis biologics, among others, were associated with a cirAE grade improvement of ≥2 grades in every patient treated. CONCLUSION: This study suggests that a multi-institutional registry of cirAEs and management is not only feasible but that the information collected can be used to detect, evaluate, and rigorously assess targeted treatments for cirAEs. Further expansion and modification to include treatment progression may allow for sufficient data for specific treatment recommendations to be made.

Development of a Skin-Directed Scoring System for Stevens-Johnson Syndrome and Epidermal Necrolysis: A Delphi Consensus Exercise.

Importance: Scoring systems for Stevens-Johnson syndrome and epidermal necrolysis (EN) only estimate patient prognosis and are weighted toward comorbidities and systemic features; morphologic terminology for EN lesions is inconsistent. Objectives: To establish consensus among expert dermatologists on EN terminology, morphologic progression, and most-affected sites, and to build a framework for developing a skin-directed scoring system for EN. Evidence Review: A Delphi consensus using the RAND/UCLA appropriateness criteria was initiated with a core group from the Society of Dermatology Hospitalists to establish agreement on the optimal design for an EN cutaneous scoring instrument, terminology, morphologic traits, and sites of involvement. Findings: In round 1, the 54 participating dermatology hospitalists reached consensus on all 49 statements (30 appropriate, 3 inappropriate, 16 uncertain). In round 2, they agreed on another 15 statements (8 appropriate, 7 uncertain). There was consistent agreement on the need for a skin-specific instrument; on the most-often affected skin sites (head and neck, chest, upper back, ocular mucosa, oral mucosa); and that blanching erythema, dusky erythema, targetoid erythema, vesicles/bullae, desquamation, and erosions comprise the morphologic traits of EN and can be consistently differentiated. Conclusions and Relevance: This consensus exercise confirmed the need for an EN skin-directed scoring system, nomenclature, and differentiation of specific morphologic traits, and identified the sites most affected. It also established a baseline consensus for a standardized EN instrument with consistent terminology.

A Case of Multiple Hemorrhagic Friable Nodules.

A man in his 50s with a history of mycosis fungoides presents with bleeding wounds and nodules on the bilateral hips and forearms. What is your diagnosis?

A Phase I Trial of SYK Inhibition with Fostamatinib in the Prevention and Treatment of Chronic Graft-Versus-Host Disease.

Despite the exciting advancement of novel therapies, chronic graft-versus-host disease (cGVHD) remains the most common cause of non-relapse mortality after allogeneic hematopoietic stem cell transplantation (HCT). Frontline treatment of cGVHD involves systemic steroids, which are associated with significant morbidities. We previously found that inhibition of spleen tyrosine kinase (SYK) with fostamatinib preferentially eradicated aberrantly activated B cells in both ex vivo studies of cGVHD patient B cells, as well as in vivo mouse studies. These and other preclinical studies implicated hyper-reactive B-cell receptor signaling and increased SYK expression in the pathogenesis of cGVHD and compelled this first in-human allogeneic HCT clinical trial. We investigated the safety and efficacy of the oral SYK inhibitor, fostamatinib, for both the prevention and treatment of cGVHD. The primary objective was to evaluate the safety of fostamatinib and determine its maximum tolerated dose in the post-HCT setting. Secondary objectives included assessing the efficacy of fostamatinib in preventing and treating cGVHD, as well as examining alterations in B-cell compartments with treatment. This was a single-institution phase I clinical trial that evaluated the use of fostamatinib in allogeneic HCT patients before the development of cGVHD or at the time of steroid-refractory cGVHD (SR-cGVHD). Patients received fostamatinib at one of three dose levels using a continual reassessment algorithm to determine the maximum tolerated dose. Multiparameter flow cytometry was used to evaluate changes in B cell subpopulations over the first year of treatment with fostamatinib. Nineteen patients were enrolled in this phase I trial, with 5 in the prophylaxis arm and 14 in the therapeutic arm. One patient (5%) required discontinuation of therapy for a dose-limiting toxicity. At a median follow-up of over 3 years, no patients had cancer relapse while on fostamatinib treatment, and recurrent malignancy was observed in 1 patient 2 years after the end of therapy. In the prophylaxis arm, 1 of 5 patients (20%) developed cGVHD while on fostamatinib. In the therapeutic arm, the overall response rate was 77%, with a complete response rate of 31%. The median duration of response was 19.3 months and the 12-month failure-free survival was 69% (95% confidence interval, 48-100). Patients were able to reduce their steroid dose by a median of 80%, with 73% remaining on a lower dose at 1 year compared to baseline. There was an early reduction in the proportion of IgD-CD38hi plasmablast-like cells with fostamatinib treatment, particularly in those SR-cGVHD patients who had an eventual response. B-cell reconstitution was not significantly impacted by fostamatinib therapy after allogeneic HCT. Fostamatinib featured a favorable safety profile in the post-HCT setting. Our data suggests an early efficacy signal that was associated with effects on expected cell targets in both the prophylaxis and treatment of cGVHD, providing rationale for a phase II investigation.

Ruxolitinib for the treatment of steroid refractory pediatric chronic graft-versus-host disease.

Chronic graft-versus-host disease (cGVHD) of the skin is a serious cause of long-term morbidity and mortality among patients who receive hematopoietic stem cell transplants. Systemic corticosteroids remain first-line treatment for cutaneous cGVHD; however, there is currently no consensus on second-line therapy for steroid-refractory disease. We herein present a case of a pediatric patient with severe cGVHD of the skin, nonresponsive to corticosteroids, who was successfully treated with a prolonged course of ruxolitinib with minimal side effects.

Clinical and direct immunofluorescence characteristics of cutaneous toxicity associated with enfortumab vedotin.

Enfortumab vedotin (EV), a novel antibody-drug conjugate approved for metastatic urothelial carcinoma, causes a variety of cutaneous adverse reactions. We present two cases of bullous eruptions following treatment with EV, both demonstrating IgG deposition on direct immunofluorescence (DIF) correlating to the location of nectin-4 in the epidermis. This suggests that the IgG component of EV binding to nectin-4 in keratinocytes is likely a primary contributor to the high rates of cutaneous toxicity.

Management of Infectious Emergencies for the Inpatient Dermatologist.

PURPOSE OF REVIEW: There are various dermatologic emergencies stemming from bacterial, viral, and fungal etiologies that can present in the inpatient setting. This review summarizes the pathogenesis and diagnosis of infections with cutaneous involvement and highlights new therapies. RECENT FINDINGS: Clindamycin inhibits toxin formation and can be used as an adjunct therapy for the staphylococcal scalded syndrome. Isavuconazole therapy for mucormycosis infection is a less toxic alternative to amphotericin B. SUMMARY: Diagnosis of these infections is primarily guided by high clinical suspicion and early recognition can prevent dangerous sequelae. Treatment mainstays have been well-established, but there are adjunctive therapies that may potentially benefit the patient.

Semi-automated weak annotation for deep neural network skin thickness measurement.

Correctly calculating skin stiffness with ultrasound shear wave elastography techniques requires an accurate measurement of skin thickness. We developed and compared two algorithms, a thresholding method and a deep learning method, to measure skin thickness on ultrasound images. Here, we also present a framework for weakly annotating an unlabeled dataset in a time-effective manner to train the deep neural network. Segmentation labels for training were proposed using the thresholding method and validated with visual inspection by a human expert reader. We reduced decision ambiguity by only inspecting segmentations at the center A-line. This weak annotation approach facilitated validation of over 1000 segmentation labels in 2 hours. A lightweight deep neural network that segments entire 2D images was designed and trained on this weakly-labeled dataset. Averaged over six folds of cross-validation, segmentation accuracy was 57% for the thresholding method and 78% for the neural network. In particular, the network was better at finding the distal skin margin, which is the primary challenge for skin segmentation. Both algorithms have been made publicly available to aid future applications in skin characterization and elastography.

Drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome.

Drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome is a severe cutaneous drug reaction characterized by fever, lymphadenopathy, hematologic abnormalities, multisystem involvement, and viral reactivation. Although most patients with DRESS syndrome are able to fully recover, a subset of patients go on to have a prolonged course with recurrence, and/or autoimmune complications. Severe systemic involvement is associated with significant morbidity and mortality. Viral reactivation, especially of human herpes virus 6, Epstein-Barr virus, and cytomegalovirus, is a common feature of DRESS, with a high viral load and antibody titers being associated with poor outcomes. Aside from prompt discontinuation of the offending drug, treatment for patients with significant disease consists of systemic therapy with corticosteroids.

Th17 cell inhibition in a costimulation blockade-based regimen for vascularized composite allotransplantation using a nonhuman primate model.

Vascularized composite allotransplantation (VCA) is challenged by the morbidity of immunosuppression required to prevent rejection. The use of highly specific biologics has not been well explored in VCA. Given that psoriasis is T-cell mediated, as is rejection of skin-containing VCAs, we sought to assess the role of ustekinumab and secukinumab, which are approved to treat psoriasis by inhibiting Th17 cells. We combined these agents with belatacept and steroids in a VCA nonhuman primate model. Group I consisted of belatacept and steroids, group II was belatacept, ustekinumab with steroid taper, and group III was belatacept, secukinumab with steroid taper. Three animals were transplanted in each group. In group I, the mean graft survival time until the first sign of rejection was 10 days whereas in group II and III it was 10.33 and 11 days, respectively. The immunohistochemistry analysis showed that the number of IL-17a+ cells and the intensity of IL-17a expression were significantly reduced in both dermis and hypodermis parts in groups II and III when compared to group I (P < 0.01). Ustekinumab and secukinumab led to less T-cell infiltration and IL-17a expression in the allograft but provided no benefit to belatacept and steroids in VCA survival.