Spatial transcriptomics reveals organized and distinct immune activation in cutaneous granulomatous disorders.

BACKGROUND: Non-infectious (inflammatory) cutaneous granulomatous disorders include cutaneous sarcoidosis (CS), granuloma annulare (GA), necrobiosis lipoidica (NL), and necrobiotic xanthogranuloma (NXG). These disorders share macrophage predominant inflammation histologically, but the inflammatory architecture and the pattern of extracellular matrix alteration varies. The underlying molecular explanations for these differences remain unclear. OBJECTIVE: To understand spatial gene expression characteristics in these disorders. METHODS: We performed spatial transcriptomics in cases of CS, GA, NL, and NXG to compare patterns of immune activation and other molecular features in a spatially resolved fashion. RESULTS: CS is characterized by a polarized, spatially organized T helper (Th) 1 predominant response with classical macrophage activation. GA is characterized by a mixed, but spatially organized pattern of Th1 and Th2 polarization with both classical and alternative macrophage activation. NL showed concomitant activation of Th1, Th2, and Th17 immunity with a mixed pattern of macrophage activation. Activation of type 1 immunity was shared among, CS, GA, and NL and included upregulation of IL-32. NXG showed upregulation of CXCR4-CXCL12/14 chemokine signaling and exaggerated alternative macrophage polarization. Histologic alteration of extracellular matrix correlated with hypoxia and glycolysis programs and type 2 immune activation. CONCLUSIONS: Inflammatory cutaneous granulomatous disorders show distinct and spatially organized immune activation that correlate with hallmark histologic changes.

Drug-induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms. Part II diagnosis and management.

Drug-induced hypersensitivity syndrome, also known as drug reaction with eosinophilia and systemic symptoms, is a severe cutaneous adverse reaction characterized by an exanthem, fever, and hematologic and visceral organ involvement. The differential diagnosis includes other cutaneous adverse reactions, infections, inflammatory and autoimmune diseases, and neoplastic disorders. Three sets of diagnostic criteria have been proposed; however, consensus is lacking. The cornerstone of management is immediate discontinuation of the suspected drug culprit. Systemic corticosteroids remain first-line therapy, but the literature on steroid-sparing agents is expanding. Longitudinal evaluation for sequelae is recommended. Adjunctive tests for risk stratification and drug culprit identification remain under investigation. Part II of this continuing medical education activity begins by exploring the differential diagnosis and diagnosis of drug-induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms and concludes with an evidence-based overview of evaluation and treatment.

Drug-induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms. Part I. Epidemiology, pathogenesis, clinicopathological features, and prognosis.

Drug-induced hypersensitivity syndrome (DiHS), also known as drug reaction with eosinophilia and systemic symptoms (DRESS), is a severe cutaneous adverse reaction (SCAR) characterized by an exanthem, fever, and hematologic and visceral organ involvement. Anticonvulsants, antibiotics, and allopurinol are the most common triggers. The pathogenesis involves a complex interplay between drugs, viruses, and the immune system primarily mediated by T-cells. DiHS/DRESS typically presents with a morbilliform eruption 2-6 weeks after drug exposure, and is associated with significant morbidity, mortality, and risk of relapse. Long-term sequelae primarily relate to organ dysfunction and autoimmune diseases. Part I of this continuing medical education activity on DiHS/DRESS provides an update on epidemiology, novel insights into pathogenesis, and a description of clinicopathological features and prognosis.

Neutrophilic dermatoses: Pathogenesis, Sweet syndrome, neutrophilic eccrine hidradenitis, and Behçet disease.

Neutrophilic dermatoses are a heterogeneous group of inflammatory skin disorders that present with unique clinical features but are unified by the presence of a sterile, predominantly neutrophilic infiltrate on histopathology. The morphology of cutaneous lesions associated with these disorders is heterogeneous, which renders diagnosis challenging. Moreover, a thorough evaluation is required to exclude diseases that mimic these disorders and to diagnose potential associated infectious, inflammatory, and neoplastic processes. While some neutrophilic dermatoses may resolve spontaneously, most require treatment to achieve remission. Delays in diagnosis and treatment can lead to significant patient morbidity and even mortality. Therapeutic modalities range from systemic corticosteroids to novel biologic agents, and the treatment literature is rapidly expanding. The first article in this continuing medical education series explores the pathogenesis of neutrophilic dermatoses and reviews the epidemiology, clinical and histopathologic features, diagnosis, and management of Sweet syndrome, neutrophilic eccrine hidradenitis, and Behçet disease.

Neutrophilic dermatoses: Pyoderma gangrenosum and other bowel- and arthritis-associated neutrophilic dermatoses.

Neutrophilic dermatoses are a heterogeneous group of inflammatory skin disorders that present with unique clinical features but are unified by the presence of a sterile, predominantly neutrophilic infiltrate on histopathology. The morphology of cutaneous lesions associated with these disorders is heterogeneous, which renders diagnosis challenging. Moreover, a thorough evaluation is required to exclude diseases that mimic these disorders and to diagnose potential associated infectious, inflammatory, and neoplastic processes. While some neutrophilic dermatoses may resolve spontaneously, most require treatment to achieve remission. Delays in diagnosis and treatment can lead to significant patient morbidity and even mortality. Therapeutic modalities range from systemic corticosteroids to novel biologic agents, and the treatment literature is rapidly expanding. The second article in this continuing medical education series reviews the epidemiology, clinical characteristics, histopathologic features, diagnosis, and management of pyoderma gangrenosum as well as bowel-associated dermatosis-arthritis syndrome and the arthritis-associated neutrophilic dermatoses rheumatoid neutrophilic dermatitis and adult Still disease.

Sweet syndrome in patients with and without malignancy: A retrospective analysis of 83 patients from a tertiary academic referral center.

BACKGROUND: Sweet syndrome is a neutrophilic dermatosis that may be categorized into classic, malignancy-associated, and drug-induced subtypes. Few studies have systematically analyzed this rare disorder. OBJECTIVE: To describe the clinicopathologic characteristics and treatment of Sweet syndrome and identify characteristics associated with concurrent malignancy. METHODS: We retrospectively reviewed patients with Sweet syndrome at the University of Pennsylvania from 2005 to 2015. RESULTS: We identified 83 patients (mean age, 57 years; 51% male) with Sweet syndrome: 30% with the classic form, 44% with the malignancy-associated form, 24% with the drug-induced form in the setting of malignancy, and 2% with the drug-induced form. Acute myeloid leukemia was the most common malignancy (in 24 of 83 patients [29%]). Filgrastim was the most common medication (used in 8 of 83 patients [10%]). Leukopenia (P < .001), anemia (P = .002), thrombocytopenia (P < .001), absence of arthralgia (P < .001), and histiocytoid or subcutaneous histopathology (P = .024) were associated with malignancy (χ2 test). LIMITATIONS: This was a retrospective study that represents patients from a single tertiary academic referral center, which may limit its generalizability to other settings. CONCLUSION: When caring for patients with Sweet syndrome, dermatologists should be aware of the potential association of leukopenia, anemia, thrombocytopenia, absence of arthralgia, and histiocytoid or subcutaneous histopathology with malignancy.

Impact of store-and-forward (SAF) teledermatology on outpatient dermatologic care: A prospective study in an underserved urban primary care setting.

BACKGROUND: The clinical value of teledermatology in the primary care setting remains relatively unknown. OBJECTIVE: We sought to determine the impact of teledermatology on outpatient diagnosis, management, and access to dermatologic care in a resource-poor primary care setting. METHODS: We performed a prospective study of store-and-forward teledermatology consults submitted between January and November 2013 from 11 underserved clinics in Philadelphia to the University of Pennsylvania using mobile devices and the Internet. We assessed diagnostic and management concordance between primary care providers and dermatologists, time to consult completion, anticipated level of dermatology input in the absence of teledermatology, and number of consults managed with teledermatology alone. RESULTS: The study included 196 consults encompassing 206 dermatologic conditions. Diagnoses and management plans of primary care providers and dermatologists were fully concordant for 22% and 23% of conditions, respectively. The median time to consult completion was 14 (interquartile range 3-28) hours. At least 61% of consults would not otherwise have received dermatology input, and 77% of consults were managed with teledermatology alone. LIMITATIONS: Lack of a diagnostic gold standard, limited patient follow-up, and uncertain generalizability are limitations. CONCLUSION: Teledermatology is an innovative and impactful modality for delivering dermatologic care to outpatients in resource-poor primary care settings.

Primary care providers' perceptions of mobile store-and-forward teledermatology.

INTRODUCTION: Although teledermatology offers promise as a tool to increase access to care, adoption has been limited. Understanding the perspectives and experiences of key stakeholders, such as primary care providers (PCPs) and patients, is important to identify opportunities to reduce barriers to adoption and to improve teledermatology programs. Although many studies have examined patients' experiences and satisfaction with teledermatology, few have examined referring PCPs' perspectives. OBJECTIVE: To identify PCPs' perceptions on the strengths and limitations of teledermatology in order to identify opportunities to improve teledermatology programs. METHODS: We distributed an anonymous, web-based survey to 30 PCPs involved in a two-year study evaluating a mobile app-based teledermatology platform. RESULTS: 100% (18/18) agreed or strongly agreed that teledermatology increases access to dermatologic care, improves patient care, and is acceptable to patients. 100% (18/18) agreed or strongly agreed that teledermatology provides educational benefit to the PCP. Only 6% (1/18) agreed that teledermatology increases medical liability and 11% (2/18) agreed that it increases risk of a breach in privacy or confidentiality. CONCLUSIONS: Our findings highlight that PCPs are highly satisfied with mobile app-based, store-and-forward teledermatology and that they believe teledermatology offers synergistic educational benefit. We hope these results will help guide the development of teledermatology programs to increase access to timely, cost-effective care.

Tele-leprology: a literature review of applications of telemedicine and tele-education to leprosy.

Global efforts to eliminate leprosy have brought about a steep decline in prevalence; however, new cases are continually detected. Without early diagnosis and appropriate management, these individuals are at risk of disability, disfigurement, and social stigma. Telemedicine and tele-education are increasingly utilised strategies to maintain access to expert healthcare for leprosy patients scattered in low-accessibility areas. However, an overview of tele-leprology, the application of these strategies specifically to leprosy, is currently unavailable. This review provides such an overview and discusses future directions for research and implementation.

Inpatient Management of Hidradenitis Suppurativa: A Delphi Consensus Study.

Inpatient hospitalization of individuals with hidradenitis suppurativa (HS) has increased. Inpatient services may not be familiar enough with this disease to understand how to manage severe HS and/or HS flares. It would be beneficial to the inpatient medical community to establish consensus recommendations on holistic inpatient care of patients with HS. A survey study was developed and distributed by Wake Forest University School of Medicine (Winston-Salem, North Carolina). A total of 26 dermatologists participated in the Delphi process, and the process was conducted in 2 rounds. Participants voted on proposal statements using a 9-point scale (1=very inappropriate; 9=very appropriate). Statements were developed using current published guidelines for management of HS and supportive care guidelines for other severe inpatient dermatologic diseases. A total of 50 statements were reviewed and voted on between the 2 rounds. Consensus was determined using the RAND/UCLA Appropriateness Method. Twenty-six dermatologists completed the first-round survey, and 24 completed the second-round survey. The 40 consensus recommendations generated through these surveys can serve as a resource for providers caring for inpatients with HS.

Defining D-irAEs: consensus-based disease definitions for the diagnosis of dermatologic adverse events from immune checkpoint inhibitor therapy.

With an increasing number of patients eligible for immune checkpoint inhibitors, the incidence of immune-related adverse events (irAEs) is on the rise. Dermatologic immune-related adverse events (D-irAEs) are the most common and earliest to manifest, often with important downstream consequences for the patient. Current guidelines lack clarity in terms of diagnostic criteria for D-irAEs. The goal of this project is to better define D-irAE for the purposes of identification, diagnosis, and future study of this important group of diseases.The objectives of this project were to develop consensus guidance for an approach to D-irAEs including disease definitions and severity grading. Knowing that consensus among oncologists, dermatologists, and irAE subspecialists would be critical for usability, we formed a Dermatologic irAE Disease Definition Panel. The panel was composed of 34 experts, including oncologists, dermatologists, a rheumatologist, and an allergist/immunologist from 22 institutions across the USA and internationally. A modified Delphi consensus process was used, with two rounds of anonymous ratings by panelists and two virtual meetings to discuss areas of controversy. Panelists rated content for usability, appropriateness, and accuracy on 9-point scales in electronic surveys and provided free text comments. A working group aggregated survey responses and incorporated them into revised definitions. Consensus was based on numeric ratings using the RAND/UCLA Appropriateness Method with prespecified definitions.Following revisions based on panelist feedback, all items received consensus in the second round of ratings. Consensus definitions were achieved for 10 core D-irAE diagnoses: ICI-vitiligo, ICI-lichen planus, ICI-psoriasis, ICI-exanthem, ICI-bullous pemphigoid, ICI-Grover's, ICI-eczematous, ICI-eruptive atypical squamous proliferation, ICI-pruritus without rash, and ICI-erosive mucocutaneous. A standard evaluation for D-irAE was also found to reach consensus, with disease-specific exceptions detailed when necessary. Each disorder's description includes further details on disease subtypes, symptoms, supportive exam findings, and three levels of diagnostic certainty (definite, probable, and possible).These consensus-driven disease definitions standardize D-irAE classification in a useable framework for multiple disciplines and will be the foundation for future work. Given consensus on their accuracy and usability from a representative panel group, we anticipate that they can be used broadly across clinical and research settings.

Identification of a neutrophil-specific PIK3R1 mutation facilitates targeted treatment in a patient with Sweet syndrome.

BackgroundAcute febrile neutrophilic dermatosis (Sweet syndrome) is a potentially fatal multiorgan inflammatory disease characterized by fever, leukocytosis, and a rash with a neutrophilic infiltrate. The disease pathophysiology remains elusive, and current dogma suggests that Sweet syndrome is a process of reactivity to an unknown antigen. Corticosteroids and steroid-sparing agents remain frontline therapies, but refractory cases pose a clinical challenge.MethodsA 51-year-old woman with multiorgan Sweet syndrome developed serious corticosteroid-related side effects and was refractory to steroid-sparing agents. Blood counts, liver enzymes, and skin histopathology supported the diagnosis. Whole-genome sequencing, transcriptomic profiling, and cellular assays of the patient's skin and neutrophils were performed.ResultsWe identified elevated IL-1 signaling in lesional Sweet syndrome skin caused by a PIK3R1 gain-of-function mutation specifically found in neutrophils. This mutation increased neutrophil migration toward IL-1ß and neutrophil respiratory burst. Targeted treatment of the patient with an IL-1 receptor 1 antagonist resulted in a dramatic therapeutic response and enabled a tapering off of corticosteroids.ConclusionDysregulated PI3K/AKT signaling is the first signaling pathway linked to Sweet syndrome and suggests that this syndrome may be caused by acquired mutations that modulate neutrophil function. Moreover, integration of molecular data across multiple levels identified a distinct subtype within a heterogeneous disease that resulted in a rational and successful clinical intervention. Future patients will benefit from efforts to identify potential mutations. The ability to directly interrogate the diseased skin allows this method to be generalizable to other inflammatory diseases and demonstrates a potential personalized medicine approach for patients with clinically challenging disease.Funding SourcesBerstein Foundation, NIH, Veterans Affairs (VA) Administration, Moseley Foundation, and H.T. Leung Foundation.