Lack of association between pandemic chilblains and SARS-CoV-2 infection.

An increased incidence of chilblains has been observed during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic and attributed to viral infection. Direct evidence of this relationship has been limited, however, as most cases do not have molecular evidence of prior SARS-CoV-2 infection with PCR or antibodies. We enrolled a cohort of 23 patients who were diagnosed and managed as having SARS-CoV-2-associated skin eruptions (including 21 pandemic chilblains [PC]) during the first wave of the pandemic in Connecticut. Antibody responses were determined through endpoint titration enzyme-linked immunosorbent assay and serum epitope repertoire analysis. T cell responses to SARS-CoV-2 were assessed by T cell receptor sequencing and in vitro SARS-CoV-2 antigen-specific peptide stimulation assays. Immunohistochemical and PCR studies of PC biopsies and tissue microarrays for evidence of SARS-CoV-2 were performed. Among patients diagnosed and managed as "covid toes" during the pandemic, we find a percentage of prior SARS-CoV-2 infection (9.5%) that approximates background seroprevalence (8.5%) at the time. Immunohistochemistry studies suggest that SARS-CoV-2 staining in PC biopsies may not be from SARS-CoV-2. Our results do not support SARS-CoV-2 as the causative agent of pandemic chilblains; however, our study does not exclude the possibility of SARS-CoV-2 seronegative abortive infections.

Inflammatory linear verrucous epidermal nevus (ILVEN) encompasses a spectrum of inflammatory mosaic disorders.

BACKGROUND: Inflammatory linear verrucous epidermal nevus (ILVEN) is a rare skin disease characterized by pruritic erythematous scaly plaques distributed along the lines of Blaschko. Two cases of ILVEN with CARD14 mutations and one case with a GJA1 mutation have been previously reported. OBJECTIVE: To elucidate the genetic cause of a cohort of patients diagnosed based on clinical and histopathological evaluation with ILVEN. METHODS: We recruited patients diagnosed with ILVEN based on clinical and histopathological criteria. Exome sequencing of affected skin with or without blood/saliva was performed and germline and somatic pathogenic variants were identified. RESULTS: Five patients were enrolled. All had skin lesions from birth or early childhood. Two patients developed psoriasis vulgaris after the diagnosis of ILVEN. The first had a germline heterozygous CARD14 mutation and a post-zygotic hotspot mutation in KRT10. The histopathologic evaluation did not show epidermolytic hyperkeratosis. The second had a post-zygotic hotspot mutation in HRAS. Her ILVEN became itchy once psoriasis developed. One patient was re-diagnosed with linear porokeratosis based on a germline mutation in PMVK and a post-zygotic second-hit mutation. Two patients were re-diagnosed with congenital hemidysplasia with ichthyosiform nevus and limb defect nevus based on germline NSDHL mutations. CONCLUSION: ILVEN is a clinical descriptor for a heterogenous group of mosaic inflammatory disorders. Genetic analysis has the potential to more precisely categorize ILVEN and permits pathogenesis-directed therapies in some cases.

Toxic epidermal necrolysis-like acute graft-versus-host disease in pediatric bone marrow transplant patients: Case series and review of the literature.

BACKGROUND/OBJECTIVES: Complications of hematopoietic stem cell transplant (HSCT) include acute graft-versus-host disease (aGVHD). Severe cutaneous aGVHD can present with generalized erythroderma, desquamation, and bullae which can mimic toxic epidermal necrolysis (TEN). TEN occurs in response to a culprit medication. Transplant patients are often on many medications, making it difficult to distinguish between the two conditions. Given that TEN-like aGVHD is rare, we describe a case series of pediatric patients and review the literature. METHODS: This is a multi-institutional case series of children who developed TEN-like aGVHD following bone marrow transplantation. Demographic, clinical, and treatment information was collected. RESULTS: Ten patients were identified. Median age at transplantation was 8.5 years (range 0.12-17 years). Median time from transplant to first skin symptoms was 35 days (range 6-110 days) and to first TEN-like symptoms was 40 days (range 16-116 days). 7/10 had other organ GVHD involvement. All patients were on concurrent medications at time of first skin symptoms including immunosuppression for GVHD prophylaxis, infection prophylaxis or treatment, and pain medication. Treatments for TEN-like aGVHD included immunosuppression. CONCLUSIONS: We observe that patients with > or equal to 50% BSA involvement of their skin with TEN-like aGVHD, extracutaneous GVHD, and lack of reepithelization tend to have poor outcomes. Given the rarity of this condition, multidisciplinary care of these patients is important for accurate and timely diagnosis and treatment.

Gentamicin Induces Laminin 332 and Improves Wound Healing in Junctional Epidermolysis Bullosa Patients with Nonsense Mutations.

Generalized severe junctional epidermolysis bullosa (GS-JEB) is an incurable and fatal autosomal recessively inherited blistering skin disease caused by mutations in the LAMA3, LAMB3, or LAMC2 genes. Most of these mutations are nonsense mutations that create premature termination codons that lead to impaired production of functional laminin 332, a protein needed for epidermal-dermal adherence. Gentamicin induces readthrough of nonsense mutations and restores the full-length protein in various genetic diseases. Using primary keratinocytes from three GS-JEB patients, we showed that gentamicin induced functional laminin 332 that reversed a JEB-associated, abnormal cell phenotype. In a subsequent open-label trial involving the same patients, we examined whether 0.5% gentamicin ointment applied topically to open skin wounds could promote nonsense mutation readthrough and create new laminin 332 in the patients' skin. Gentamicin-treated wounds exhibited increased expression of laminin 332 at the dermal-epidermal junction for at least 3 months and were associated with improved wound closure. There were no untoward side effects from topical gentamicin. The newly induced laminin 332 did not generate anti-laminin 332 autoantibodies in either the patients' blood or skin. Gentamicin readthrough therapy may be a treatment for GS-JEB patients with nonsense mutations.

Epidermolysis bullosa pruriginosa treated with dupilumab.

Epidermolysis bullosa pruriginosa (EBP) is a variant of dystrophic epidermolysis bullosa characterized by intense pruritus and prurigo nodularis-like lesions. While medical therapies for EBP exist, current treatments are not consistently effective, and symptoms often cause decreased quality of life. Here, we report two cases of EBP treated with dupilumab, which decreased symptoms of pruritus and improved skin findings. Both patients have been on dupilumab for over one year with sustained improvement and no adverse effects; although in one patient, increased dosing was required to attain optimal control of disease.

Trends in office visits and treatment for urticaria in children in the United States, 1998-2016.

BACKGROUND/OBJECTIVES: Urticaria is a common condition with an estimated prevalence of up to 23% in the pediatric population. Studies characterizing visits and treatments for urticaria in the pediatric population are unavailable. Understanding visit and treatment trends for urticaria in the pediatric population may help inform care for patients with urticaria. METHODS: A total of 108 278 outpatient records from the National Ambulatory Medical Care Survey representing 3.4 billion visits by patients of age 18 and younger were analyzed. This study included the calendar years 1998 through 2016. RESULTS: Pediatricians saw the largest proportion of all visits (52.7%). Male and female patients accounted for approximately equal proportions of all visits for urticaria. There was a slight male predominance in visits to pediatricians (53.7%), whereas dermatologists saw female patients more frequently (63.3%). Most visits for urticaria were by non-Hispanic (78.1%) and White (78.2%) patients. H1 antihistamines were the most commonly prescribed treatment (70.3%), whereas topical corticosteroids were prescribed least frequently (4.9%). Topical corticosteroids were most frequently prescribed by dermatologists (7.7%). Non-H1 antihistamine and non-corticosteroid therapy were prescribed in 9.7% of all visits and in 4.5% of visits to pediatricians. Most visits for urticaria were to physicians in metropolitan areas (88.8%). Pediatricians saw the highest number of non-metropolitan area visits (56.3%). CONCLUSIONS: H1 antihistamines were the most commonly used therapy (70%), consistent with established treatment guidelines. Male and female pediatric patients present equally often for urticaria, but sex differences were seen with visit frequencies to certain specialties.

Persistent dysesthesias in involuted infantile hemangiomas: An uncommon complication in a common condition.

BACKGROUND/OBJECTIVES: Infantile hemangiomas (IHs) are common benign vascular tumors of infancy. IHs tend to grow in the first few months of life and then gradually involute over years, often leaving fibrofatty residua or textural changes in their place. Classically, these lesions are painless throughout their entire natural history; however, we now report on seven patients with involuted IH with intermittent but persistent sensory symptoms. METHODS: This is a multicenter case series in which members of the Birthmarks Focused Study Group of the Pediatric Dermatology Research Alliance (PeDRA) and the Hemangioma Investigator Group contributed patients with IH and dysesthesias from their clinical practices. Charts were then reviewed to document clinical details. RESULTS: Seven patients were included, presenting at an average age of 14.6 years (range 3-48 years) for complaints related to discomfort in the region of involuted IH. The majority (6/7) reported pain or tenderness to the area. One patient reported pruritus. All patients reported intermittent symptoms. The length of symptoms ranged between 4 months and 5 years. Treatment was attempted in 5/7 patients. Ice, oral propranolol, topical capsaicin, and intralesional triamcinolone partially improved symptoms. CONCLUSIONS: Persistent cutaneous dysesthesias were present in seven patients, in most cases many years after completion of involution. Further research is needed to fully elucidate the pathophysiology and optimal treatments for this IH complication.

Off-label use of dupilumab for pediatric patients with atopic dermatitis: A multicenter retrospective review.

BACKGROUND: Atopic dermatitis (AD) is a common, chronic type 2 inflammatory skin disease, typically starting in infancy, with increased risk for subsequent extracutaneous atopic morbidities. Dupilumab is the first biologic agent targeting type 2 inflammation approved by the U.S. Food and Drug Administration (USFDA); it was licensed in 2017 for adults with moderate to severe AD and 2 years later for adolescents. Systemic treatment for pediatric AD remains a significant unmet medical need. OBJECTIVE: To analyze off-label use of dupilumab in children with AD. METHODS: Multicenter retrospective review that evaluated children who were prescribed dupilumab for moderate to severe AD. RESULTS: One hundred eleven of 124 patients (89.5%) gained access to dupilumab after a mean of 9 weeks. The dosing range was 4 to 15.5 mg/kg for the loading dose and 2.0 to 15.3 mg/kg every other week for maintenance. The range was widest for 6- to 11-year-olds and was related to use of either full or half of adult dosing. Associated morbidities, treatment response, and adverse events were comparable to those in previous adolescent and adult trials. LIMITATIONS: The retrospective design of the study limited uniform data collection. CONCLUSION: Access to dupilumab was achievable for the majority of children after a mean 9-week delay because of insurance payment denial. This review supports dupilumab response and tolerability in children. Optimal dosing for patients younger than 12 years has not been defined. Availability of the drug in 2 different concentrations is an important safety issue.

Post-zygotic ACTB mutations underlie congenital smooth muscle hamartomas.

BACKGROUND: Congenital smooth muscle hamartomas (CSMHs) are benign lesions that share clinical and histopathological features with Becker nevus, a mosaic disorder associated with post-zygotic ACTB mutations. Given the clinical and histopathological overlap between CSMH and Becker nevus, we hypothesized that post-zygotic mutations in ACTB may underlie CSMH. METHODS: Direct sequencing of ACTB gene in affected and unaffected tissue isolated from one case of hemihypertrichosis and hemihypertrophy corresponding to giant segmental CSMH and hemihypertrophy. This was followed by direct sequencing with and without enrichment assay for hotspot ACTB mutations in affected tissue from 12 samples of isolated CSMH from unrelated individuals. RESULTS: In total we identified somatic missense ACTB mutations in 9 out of 13 CSMHs (69%). Mutations were either novel or previously reported in Becker nevi and Becker nevus syndrome. CONCLUSIONS: CSMHs result from post-zygotic ACTB mutations. This study proves that CSMHs and Becker nevi are nosologically related, and expand the phenotypic spectrum of ACTB mutations.

Histopathologic findings characteristic of CARD14-associated papulosquamous eruption.

BACKGROUND: Pathogenic mutations in caspase recruitment domain-containing protein 14 (CARD14) lead to CARD14-associated papulosquamous eruption, which shares clinicopathologic findings with psoriasis and pityriasis rubra pilaris. We aimed to describe distinguishing histopathologic features of CARD14-associated papulosquamous eruption. METHODS: This retrospective study examined the histopathologic features of specimens from patients with confirmed CARD14-associated papulosquamous eruption and adult patients with plaque psoriasis and pityriasis rubra pilaris. RESULTS: Lesional skin biopsies from patients with CARD14-associated papulosquamous eruption consistently showed alternating checkerboard parakeratosis and orthokeratosis, acanthosis without acantholysis, and dilated vessels in the dermal papillae, with some cases also showing follicular plugging. CONCLUSION: CARD14-associated papulosquamous eruption has a range of findings, with a predominance of features typically associated with pityriasis rubra pilaris.

Treatment of MEK inhibitor-induced paronychia with doxycycline.

A 12-year-old girl with neurofibromatosis type 1 and a large facial plexiform neurofibroma had been participating in a selumetinib clinical trial for the past 5 years. Despite decreased tumor size, she developed recalcitrant selumetinib-induced paronychia. Various antibiotics, topical medications, and surgeries were only minimally effective. Full-dose doxycycline resolved the paronychia, and sub-antimicrobial dosing has prevented recurrences for several months, permitting her to continue her selumetinib course.

Somatic Mutations in NEK9 Cause Nevus Comedonicus.

Acne vulgaris (AV) affects most adolescents, and of those affected, moderate to severe disease occurs in 20%. Comedones, follicular plugs consisting of desquamated keratinocytes and sebum, are central to its pathogenesis. Despite high heritability in first-degree relatives, AV genetic determinants remain incompletely understood. We therefore employed whole-exome sequencing (WES) in nevus comedonicus (NC), a rare disorder that features comedones and inflammatory acne cysts in localized, linear configurations. WES identified somatic NEK9 mutations, each affecting highly conserved residues within its kinase or RCC1 domains, in affected tissue of three out of three NC-affected subjects. All mutations are gain of function, resulting in increased phosphorylation at Thr210, a hallmark of NEK9 kinase activation. We found that comedo formation in NC is marked by loss of follicular differentiation markers, expansion of keratin-15-positive cells from localization within the bulge to the entire sub-bulge follicle and cyst, and ectopic expression of keratin 10, a marker of interfollicular differentiation not present in normal follicles. These findings suggest that NEK9 mutations in NC disrupt normal follicular differentiation and identify NEK9 as a potential regulator of follicular homeostasis.

GNA14 Somatic Mutation Causes Congenital and Sporadic Vascular Tumors by MAPK Activation.

Vascular tumors are among the most common neoplasms in infants and children; 5%-10% of newborns present with or develop lesions within the first 3 months of life. Most are benign infantile hemangiomas that typically regress by 5 years of age; other vascular tumors include congenital tufted angiomas (TAs), kaposiform hemangioendotheliomas (KHEs), and childhood lobular capillary hemangiomas (LCHs). Some of these lesions can become locally invasive and unresponsive to pharmacologic intervention, leading to significant complications. Recent investigation has revealed that activating mutations in HRAS, KRAS, NRAS, GNAQ, and GNA11 can cause certain types of rare childhood vascular tumors, and we have now identified causal recurrent somatic activating mutations in GNA14 by whole-exome and targeted sequencing. We found somatic activating GNA14 c.614A>T (p.Gln205Leu) mutations in one KHE, one TA, and one LCH and a GNA11 c.547C>T (p.Arg183Cys) mutation in two LCH lesions. We examined mutation pathobiology via expression of mutant GNA14 or GNA11 in primary human endothelial cells and melanocytes. GNA14 and GNA11 mutations induced changes in cellular morphology and rendered cells growth-factor independent by upregulating the MAPK pathway. Our findings identify GNA14 mutations as a cause of childhood vascular tumors, offer insight into mechanisms of oncogenic transformation by mutations affecting Gaq family members, and identify potential targets for therapeutic intervention.

Phenotype of CM-AVM2 caused by variants in EPHB4: how much overlap with hereditary hemorrhagic telangiectasia (HHT)?

PURPOSE: EPHB4 variants were recently reported to cause capillary malformation-arteriovenous malformation 2 (CM-AVM2). CM-AVM2 mimics RASA1-related CM-AVM1 and hereditary hemorrhagic telangiectasia (HHT), as clinical features include capillary malformations (CMs), telangiectasia, and arteriovenous malformations (AVMs). Epistaxis, another clinical feature that overlaps with HHT, was reported in several cases. Based on the clinical overlap of CM-AVM2 and HHT, we hypothesized that patients considered clinically suspicious for HHT with no variant detected in an HHT gene (ENG, ACVRL1, or SMAD4) may have an EPHB4 variant. METHODS: Exome sequencing or a next-generation sequencing panel including EPHB4 was performed on individuals with previously negative molecular genetic testing for the HHT genes and/or RASA1. RESULTS: An EPHB4 variant was identified in ten unrelated cases. Seven cases had a pathogenic EPHB4 variant, including one with mosaicism. Three cases had an EPHB4 variant of uncertain significance. The majority had epistaxis (6/10 cases) and telangiectasia (8/10 cases), as well as CMs. Two of ten cases had a central nervous system AVM. CONCLUSIONS: Our results emphasize the importance of considering CM-AVM2 as part of the clinical differential for HHT and other vascular malformation syndromes. Yet, these cases highlight significant differences in the cutaneous presentations of CM-AVM2 versus HHT.

Phenotypic expansion of POFUT1 loss of function mutations in a disorder featuring segmental dyspigmentation with eczematous and folliculo-centric lesions.

Appearance of mosaic disorders in thin Blaschko lines suggests that somatic mutations in keratinocyte precursors underlie their pathogenesis. Germline heterozygous mutations in POFUT1 gene cause Dowling-Degos disease (DDD), a skin disease that features flexural reticulated hyperpigmentation and follicular-based lesions. POFUT1 mosaicism has not been described to date. Here, we describe a 9-year-old female with segmental hyper- and hypopigmented patches with overlying eczematous plaques and follicular papules. Employing paired whole exome sequencing of saliva and keratinocytes isolated from affected skin, we found a novel germline heterozygous POFUT1 deletion causing frameshift and premature codon termination and somatic copy-neutral loss of heterozygosity on chromosome 20 encompassing POFUT1. Expression levels of POFUT1 as well as other key regulators of the notch signaling pathway-NOTCH1, NOTCH2, and HES1-were reduced in affected keratinocytes compared with normal keratinocytes. Our findings provide the first evidence of POFUT1 postzygotic mutation and a phenotypic expansion of POFUT1 loss of function mutations. We show that a recessive loss of function mutation in POFUT1 produces a distinct clinical presentation with features (e.g., dermatitis) that are absent in the generalized form of DDD. This study demonstrates how analysis of mosaic disorders can reveal unexpected phenotypes for known genes.

Review of genodermatoses with characteristic histopathology and potential diagnostic delay.

Advances in human genetics have enabled discovery of new genes for inherited skin diseases and cutaneous malformations as well as refined categorization of genodermatoses. Careful phenotyping has been central to genetic discoveries, and it provides critical clues for clinical diagnoses, particularly when the skin disorder is not congenital. This article will review several lesser-known genodermatoses that often present after infancy with recognizable histopathologic features.

An Open Label Study of an Occlusive Heat Patch in the Treatment of Warts

Background: Local hyperthermia has been demonstrated to be a safe and efficacious treatment for warts. Objective: We aimed to evaluate the safety and efficacy of an epicutaneous heat patch to induce local hyperthermia for the treatment of warts. Methods: We performed an uncontrolled, proof of concept study by applying a novel, reproducible, epicutaneous heat patch to a target wart for 2 hours per day for 12 weeks. There were 15 evaluable participants. An untreated wart was also observed and measured. Wart measurements included the diameter in two dimensions, an investigator global assessment (IGA) score, wart clearance, and monitoring for adverse events as endpoints at week 12 (end of treatment) and week 24 (end of study). Results: No major adverse events were observed. 6.7% of participants reported minor cutaneous events. At week 24, 46.7% of participants achieved complete clearance of both warts. Limitations: The small sample size and lack of independent control in each participant were the main limiting factors. Conclusion: Local hyperthermia delivered by epicutaneous heat patches was well-tolerated, safe, and achieved complete clearance in both treated as well untreated warts in 46.7% of participants at week 24 after 12 weeks of daily use. Clinicaltrials.gov: NCT01746056 J Drugs Dermatol. 2019;18(4):368-373.

Tufted angioma with associated Kasabach-Merritt phenomenon caused by somatic mutation in GNA14.

Tufted angioma (TA) is a rare vascular tumor characterized by histologic tufts of proliferating capillaries that occurs in infancy or early childhood, with a poorly understood pathogenesis. Though benign, TA can be associated with the Kasabach-Merritt phenomenon (KMP), a life-threatening consumptive coagulopathy and thrombocytopenia. Here, we explored the genetic mechanism underlying a case of TA associated with KMP via targeted sequencing of laser capture micro-dissected lesion and blood DNA, and identified a somatic, activating GNA14 mutation specific to the tumor. Our findings support aberrant GNA14 activation underlies the pathogenesis of TA associated with KMP.

CARD14-associated papulosquamous eruption: A spectrum including features of psoriasis and pityriasis rubra pilaris.

BACKGROUND: Heterozygous mutations in caspase recruitment domain family member 14 gene (CARD14) have been shown to be associated with psoriasis and familial pityriasis rubra pilaris (PRP). Many subjects with CARD14 mutations display features of both disorders, which can result in diagnostic uncertainty. In addition, these eruptions are often recalcitrant to conventional psoriasis therapies such as methotrexate, oral retinoids, and tumor necrosis factor-α inhibitors. OBJECTIVE: We sought to describe the clinical characteristics, family history, and response to therapy in subjects with papulosquamous eruptions due to mutations in CARD14. METHODS: Subjects were referred for genetic testing as part of a registry of subjects with inherited disorders of keratinization. DNA was isolated from blood or saliva, and multiplex targeted sequencing or whole exome sequencing was performed. Clinical histories of subjects with CARD14 mutations were reviewed. RESULTS: We identified 15 kindreds with CARD14-associated papulosquamous eruption (CAPE). Characteristic features of CAPE include early age of onset; prominent involvement of the cheeks, chin, and ears; family history of psoriasis or PRP; minimal response to conventional topical and systemic psoriasis therapies; and improvement with ustekinumab. LIMITATIONS: Relatively small sample size. CONCLUSIONS: Many subjects with CARD14 mutations display characteristics of both psoriasis and PRP. We propose the term CARD14-associated papulosquamous eruption to describe this spectrum of disease. Subjects with clinical features suggestive of CAPE should undergo CARD14 sequencing and may benefit from treatment with ustekinumab.