Paradoxical Psoriasis.

Cytokine blocking therapies have revolutionized the management of psoriasis and atopic dermatitis but can lead to the development of paradoxic psoriasis (PP). Patients treated with biologics should be closely monitored for the development of PP and other paradoxical eruptions (including inflammatory joint disease, inflammatory bowel disease, eczematous eruptions, lupus like eruptions, sarcoidal eruptions, and others) and occasionally the development of cutaneous T-cell lymphoma. Further understanding the immunologic mechanism of these processes will ultimately drive our understanding of and ability to predict and manage PPs.

IL17A mRNA Staining Distinguishes Palmoplantar Psoriasis from Hyperkeratotic Palmoplantar Eczema in Diagnostic Skin Biopsies.

Acral dermatoses, including hyperkeratotic palmoplantar eczema (HPE), palmoplantar psoriasis (PP), and mycosis fungoides palmaris et plantaris (MFPP), can be challenging to diagnose clinically and histopathologically. In this setting, cytokine biomarkers may be able to help provide diagnostic clarity. Therefore, we evaluated IL-17A, IFN-γ, and IL-13 expression in PP, HPE, and MFPP and compared their expression profiles with nonacral sites. We used biopsy specimens from the Yale Dermatopathology database, selecting cases of HPE (n = 12), PP (n = 8), MFPP (n = 8), normal acral skin (n = 9), nonacral eczema (n = 10), and nonacral psoriasis (n = 10) with classic clinical and histopathologic features. IL17A mRNA expression by RNA in situ hybridization differentiated PP (median score 63.1 [interquartile range 9.4-104.1]) from HPE (0.8 [0-6.0]; P = 0.003), MFPP (0.6 [0-2.6]; P = 0.003), and normal acral skin (0 [0-0]; P < 0.001). Unexpectedly, both PP and HPE showed co-expression of IFNG and IL13 mRNA. In contrast, nonacral psoriasis and eczema showed divergent patterns of IFNG and IL13 mRNA expression. Taken together, we show that IL17A mRNA expression may be a useful biomarker of PP, and we further show that acral dermatoses exhibit distinct immunology compared to nonacral sites, with implications for clinical management.

Paradoxical eruptions to targeted therapies in dermatology: A systematic review and analysis.

BACKGROUND: Antibody-based therapies that inhibit proinflammatory cytokine signaling are commonly used in dermatology. Paradoxically, these medications may induce or exacerbate inflammatory disorders. OBJECTIVE: To summarize the spectrum of manifestations, incidence, timing, potential mechanisms of, and general management approaches to paradoxical cutaneous reactions induced by cytokine-targeted antibodies in dermatology. METHODS: We performed a systematic review and analysis of published cases of cutaneous paradoxical reactions (PRs) reported in association with tumor necrosis factor α, interleukin (IL) 12/23 (p40), IL-17A/17R, IL-23 (p19), and IL-4Rα inhibitors. RESULTS: We identified 313 articles reporting 2049 cases of PRs. Tumor necrosis factor α inhibitors resulted in 91.2% (1869/2049) of all cases, followed by IL-17/17R (3.5%), IL-4Rα (2.7%), IL-12/23 (2.4%), and IL-23 (0.01%) inhibitors. Psoriasiform and eczematous eruptions were the most commonly reported, but a wide spectrum of patterns were described. Phenotypically overlapping reaction patterns were common. Time to onset typically ranged from weeks to months but could occur more than a year later. Improvement or resolution upon discontinuation of the inciting drug was common. LIMITATIONS: This was a retrospective analysis. CONCLUSIONS: Familiarity with the clinical features of PRs from cytokine-blocking antibodies may facilitate efficient recognition and management.

Sangivamycin is highly effective against SARS-CoV-2 in vitro and has favorable drug properties.

Sangivamycin is a nucleoside analog that is well tolerated by humans and broadly active against phylogenetically distinct viruses, including arenaviruses, filoviruses, and orthopoxviruses. Here, we show that sangivamycin is a potent antiviral against multiple variants of replicative severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with half-maximal inhibitory concentration in the nanomolar range in several cell types. Sangivamycin suppressed SARS-CoV-2 replication with greater efficacy than remdesivir (another broad-spectrum nucleoside analog). When we investigated sangivamycin's potential for clinical administration, pharmacokinetic; absorption, distribution, metabolism, and excretion (ADME); and toxicity properties were found to be favorable. When tested in combination with remdesivir, efficacy was additive rather than competitive against SARS-CoV-2. The proven safety in humans, long half-life, potent antiviral activity (compared to remdesivir), and combinatorial potential suggest that sangivamycin is likely to be efficacious alone or in combination therapy to suppress viremia in patients. Sangivamycin may also have the ability to help combat drug-resistant or vaccine-escaping SARS-CoV-2 variants since it is antivirally active against several tested variants. Our results support the pursuit of sangivamycin for further preclinical and clinical development as a potential coronavirus disease 2019 therapeutic.

Nivolumab-induced localized genital bullous pemphigoid in a 60-year-old male.

A 60-year-old man with metastatic renal cell carcinoma presented with a 6-month history of a pruritic, exquisitely painful genital eruption appearing 3 months after initiation of nivolumab. Examination demonstrated a poorly defined, lichenified scrotal plaque studded with erosions, yellow crust, and tense vesicles. There was no other lesion on the body or mucosae. Histopathology revealed a subepidermal blister with a mixed lymphocytic, neutrophilic, and eosinophilic infiltrate. Direct immunofluorescence of perilesional skin demonstrated subclinical blister and linear/fibrillary patchy IgG and IgA along the dermoepidermal junction. Bullous pemphigoid (BP) serologies revealed normal IgG BP230 antibodies and minimally elevated IgG BP180 antibodies. Indirect immunofluorescence revealed positive IgG at the basement membrane ("epidermal pattern") in human split skin and monkey esophagus substrates; no IgA antibodies were detected. The patient was diagnosed with nivolumab-induced localized genital BP (LGBP). BP is a reported adverse effect of immune checkpoint inhibitors including nivolumab; however, cases are typically generalized. LGBP is a rare BP variant typically presenting in children and females; there are few reports of LGBP in adult males. We report a novel case of nivolumab-induced LGBP with unique histopathologic and clinical challenges. LGBP should be considered in patients on immune checkpoint inhibitor therapy with bullous genital eruptions.

Treatment of Persistent Erythema Multiforme With Janus Kinase Inhibition and the Role of Interferon Gamma and Interleukin 15 in Its Pathogenesis.

IMPORTANCE: Persistent erythema multiforme (PEM) is poorly understood and lacks effective therapies other than glucocorticoids. OBJECTIVE: To report outcomes following treatment of PEM with Janus kinase (JAK) inhibition and to elucidate cytokine drivers of erythema multiforme (EM). DESIGN, SETTING, AND PARTICIPANTS: This was a retrospective case series of 4 patients with PEM treated with tofacitinib and/or upadacitinib in 2015 to 2021 at the dermatology clinics of 2 major tertiary referral centers. Four consecutive patients with PEM refractory to multiple treatment approaches were treated. In 1 patient, skin biopsy specimens were obtained for RNA sequencing and proteomic analysis before and during treatment. Molecular findings were validated through RNA in situ hybridization analysis of cytokine expression in biopsy specimens from a total of 12 patients with EM (3 treated with tofacitinib in this study and 9 historic samples). INTERVENTIONS: Treatment with tofacitinib, 5 to 10 mg, twice daily or upadacitinib, 15 mg, once daily. MAIN OUTCOMES AND MEASURES: Change in PEM activity was assessed in all 4 patients treated with a JAK inhibitor. Median (range) follow-up was 20.5 months (10.0-36.0 mo). RESULTS: The study population of 4 female patients had a mean (SD) age of 46.2 (13.7) years and a mean (SD) disease duration of 21.75 (11.30) years. Marked clinical improvement was noted in all 4 patients. In 1 patient with a robust improvement following treatment with tofacitinib, RNA sequencing identified interferon gamma (IFN-γ) and interleukin 15 (IL-15) as cytokines with activity both highly upregulated at baseline in lesional skin and subsequently suppressed following tofacitinib treatment. Measurement of IFNG- and IL15-positive cells in additional EM biopsy specimens of 12 patients showed significant upregulation of IFNG (8.72 cells per mm; 95% CI, 2.60-14.84) and IL15 (14.13 cells per mm; 95% CI, 0.14-28.11) compared with normal skin (P = .008 and P = .045, respectively). CONCLUSIONS AND RELEVANCE: The results of this case series study suggest that JAK inhibition may be effective in treating PEM and that IFN-γ and IL-15 may be important cytokine mediators of the disease.

Unilesional granulomatous pigmented purpuric dermatosis in a 7-year-old boy.

Granulomatous pigmented purpuric dermatoses (PPD) are rarely reported. We present a case of granulomatous PPD in a 7-year-old boy, one of only two pediatric cases with reported solitary disease. The pathogenesis of unilesional granulomatous PPD may be different from the more commonly described multifocal/widespread disease variant.

Computationally guided personalized targeted ablation of persistent atrial fibrillation.

Atrial fibrillation (AF)-the most common arrhythmia-significantly increases the risk of stroke and heart failure. Although catheter ablation can restore normal heart rhythms, patients with persistent AF who develop atrial fibrosis often undergo multiple failed ablations, and thus increased procedural risks. Here, we present personalized computational modelling for the reliable predetermination of ablation targets, which are then used to guide the ablation procedure in patients with persistent AF and atrial fibrosis. First, we show that a computational model of the atria of patients identifies fibrotic tissue that, if ablated, will not sustain AF. Then, we report the results of integrating the target ablation sites in a clinical mapping system and testing its feasibility in ten patients with persistent AF. The computational prediction of ablation targets avoids lengthy electrical mapping and could improve the accuracy and efficacy of targeted AF ablation in patients while eliminating the need for repeat procedures.

High speed ink aggregates are ejected from tattoos during Q-switched Nd:YAG laser treatments.

INTRODUCTION: Dark material has been observed embedded within glass slides following Q-switched Nd:YAG laser treatment of tattoos. It appears that these fragments are ejected at high speed from the skin during the treatment. METHOD: Light microscopic analysis of the slides reveals aggregates of dark fragmented material, presumably tattoo ink, with evidence of fractured/melted glass. Photomicrographs reveal that the sizes of these aggregates are in the range 12 µm to 0.5 mm. RESULTS: Tattoo ink fragments were clearly observed on the surface and embedded within glass slides. Surface aggregates were observed as a fine dust and were easily washed off while deeper fragments remained in situ. The embedded fragments were not visible to the unaided eye. Some fragments appeared to have melted yielding an "insect-like" appearance. These were found to be located between approximately 0.2 and 1 mm deep in the glass. CONCLUSION: Given the particle masses and kinetic energies attained by some of these aggregates their velocities, when leaving the skin, may be hundreds to thousands of metres per second. However, the masses of the aggregates are minuscule meaning that laser operators may be subjected to these high-speed aggregates without their knowledge. These high-speed fragments of ink may pose a contamination risk to laser operators. Lasers Surg. Med. 9999:1-7, 2018. © 2018 Wiley Periodicals, Inc.

Putative Intravascular Myofibroma Mimicking a Vascular Malformation With Phleboliths.

Myofibroma is a rare, benign myofibroblastic tumor that commonly presents at birth or in early infancy, usually as a painless, slow-growing, solitary, nodular mass. We present a case of a 40-year-old woman with a painful, solitary, myofibroma on the right elbow. The unique features of this case include age and gender of the patient, site, pain on presentation, tumor morphology, and putative intravascular nature of the tumor.

A novel, simple and efficacious technique for tattoo removal resulting in less pain using the Q-switched Nd:YAG laser.

A new yet simple technique has been tested on patients seeking tattoo removal by Q-switched Nd:YAG laser based on an observational study. The technique involves application of a glass microscope slide on the treatment area with a firm pressure to compress the skin which results in evacuating the blood from the capillary plexus. Results from a survey of 31 patients revealed that most felt less pain and reported less epidermal damage post-treatment. This new technique is easy to apply and inexpensive, using standard, conventional Q-switched lasers.