Extracutaneous manifestations and complications of inherited epidermolysis bullosa: part I. Epithelial associated tissues

Practical management of epidermolysis bullosa: consensus clinical position statement from the European Reference Network for Rare Skin Diseases

Inherited epidermolysis bullosa (EB) comprises rare disorders that manifest with fragility and blistering of the skin and mucous membranes, with variable clinical severity. Management of EB is challenging due to disease rarity and complexity, the wide range of extracutaneous manifestations and a profound impact on daily life for the patient and family members. Although reference centres providing multidisciplinary care for EB exist in each European country, it is common for healthcare professionals that are not specialized in this rare disorder to treat EB patients. Here, experts of the European Reference Network for Rare and Undiagnosed Skin Diseases (ERN-Skin, https://ern-skin.eu) propose practical recommendations for the diagnosis and management of the commonest clinical issues, skin blisters and wounds, oral manifestations, pain and itch.

Dominant dystrophic epidermolysis bullosa with congenital absence of skin and brachydactyly of the great toes

Epidermolysis bullosa (EB) encompasses a phenotypically and genetically heterogeneous group of inherited skin disorders characterized by blistering and erosions of the skin with minimal trauma. Dystrophic EB (DEB), both dominant and recessive, can be associated with several extracutaneous manifestations, including musculoskeletal deformities. Congenital deformities of the feet have rarely been reported in the literature. We describe an infant with dominant DEB and congenital absence of the skin who presented with congenital brachydactyly of the bilateral great toes.

Anesthetic Management of Adults With Epidermolysis Bullosa

Epidermolysis bullosa (EB) is a group of rare, inherited diseases characterized by skin fragility and multiorgan system involvement that presents many anesthetic challenges. Although the literature regarding anesthetic management focuses primarily on the pediatric population, as life expectancy improves, adult patients with EB are more frequently undergoing anesthesia in nonpediatric hospital settings. Safe anesthetic management of adult patients with EB requires familiarity with the complex and heterogeneous nature of this disease, especially with regard to complications that may worsen during adulthood. General, neuraxial, and regional anesthetics have all been used safely in patients with EB. A thorough preoperative evaluation is essential. Preoperative testing should be guided by EB subtype, clinical manifestations, and extracutaneous complications. Advanced planning and multidisciplinary coordination are necessary with regard to timing and operative plan. Meticulous preparation of the operating room and education of all perioperative staff members is critical. Intraoperatively, utmost care must be taken to avoid all adhesives, shear forces, and friction to the skin and mucosa. Special precautions must be taken with patient positioning, and standard anesthesia monitors must be modified. Airway management is often difficult, and progressive airway deterioration can occur in adults with EB over time. A smooth induction, emergence, and postoperative course are necessary to minimize blister formation from excess patient movement. With careful planning, preparation, and precautions, adult patients with EB can safely undergo anesthesia.

Clinical Perspectives of Gene-Targeted Therapies for Epidermolysis Bullosa

New insights into molecular genetics and pathomechanisms in epidermolysis bullosa (EB), methodological and technological advances in molecular biology as well as designated funding initiatives and facilitated approval procedures for orphan drugs have boosted translational research perspectives for this devastating disease. This is echoed by the increasing number of clinical trials assessing innovative molecular therapies in the field of EB. Despite remarkable progress, gene-corrective modalities, aimed at sustained or permanent restoration of functional protein expression, still await broad clinical availability. This also reflects the methodological and technological shortcomings of current strategies, including the translatability of certain methodologies beyond preclinical models as well as the safe, specific, efficient, feasible, sustained and cost-effective delivery of therapeutic/corrective information to target cells. This review gives an updated overview on status, prospects, challenges and limitations of current gene-targeted therapies.

Epidermolysis bullosa with pyloric atresia associated with compound heterozygous ITGB4 pathogenic variants: Minimal skin involvement but severe mucocutaneous disease

We report a case of junctional epidermolysis bullosa with pyloric atresia (JEB-PA) with minimal skin involvement but severe protein-losing enteropathy and airway involvement. Genetic analysis revealed heterozygous mutations in the ITGB4 gene encoding integrin β4 protein. Parental testing confirmed inheritance of frameshift variant (c.794dupC) as maternal and splice site variant (c.1608C>T/p.Cys536Cys) as paternal. Immunofluorescence mapping of her skin revealed a subepidermal blister with decreased and frayed integrin β4 at both the floor and the roof of the blister, while the intestinal mucosa showed complete absence of integrin β4. We review the literature and discuss the differential expression of integrins in the skin and gastrointestinal tract, as well as the role of chronic inflammation in the pathogenesis of EB.

Prevalence and antimicrobial resistance profile of Staphylococcus aureus in inherited epidermolysis bullosa: a cross-sectional multicenter study in Brazil

BACKGROUND

Infection is an important complication of epidermolysis bullosa (EB), and Staphylococcus aureus has been pointed out as the most common pathogen among this population. The objective of this study was to investigate the prevalence and antimicrobial resistance profile of S. aureus colonizing EB patients in Brazil.

METHODS

This cross-sectional multicenter study was conducted between December 2015 and December 2017. We included a total of 89 individuals with EB from medical centers across Brazil. Data were obtained through clinical and bacteriological investigation. S. aureus were identified by biochemical tests. The nuc and mecA genes were confirmed by PCR assay. Antimicrobial susceptibility was investigated by disk diffusion method.

RESULTS

The overall prevalence of S. aureus was 51.7% (46/89). Methicillin-resistant S. aureus (MRSA) was detected in 24.7% (19/77) of all S. aureus isolates, colonizing 15.7% (14/89) of all patients. Community-associated (CA)-MRSA strains were resistant against sulfamethoxazole/trimethoprim and levofloxacin (P < 0.05%). S. aureus colonization of the nares and belly button represented a 3.4 times higher risk of simultaneous skin lesion colonization (P < 0.05%).

CONCLUSIONS

The high frequency of MRSA colonizing patients with EB is alarming considering its association with life-threatening complications and poorer outcomes. EB patients are at increased risk of colonization and infection by Staphylococcus aureus and CA-MRSA. Getting to know S. aureus carriage sites and its antimicrobial susceptibility profile is key when planning new individualized and more effective prophylactic and therapeutic measures.

Kidney and Urinary Tract Involvement in Epidermolysis Bullosa: Is Routine Follow-Up Necessary?

Background

Several renal and urinary tract complications have been reported in patients with epidermolysis bullosa.

Objective

This study investigated kidney and urinary tract involvement in patients with epidermolysis bullosa.

Patients and Methods

Patients with epidermolysis bullosa in treatment at the Dermatology Unit were included in the study. Glomerular and tubular functions were investigated.

Results

The study included 16 patients (4 females, 12 males) of mean 11.1 years (SD = 8.1 years). Estimated GFR was normal in all patients except one with end-stage renal disease. Excluding this patient, the urinary albumin/creatinine ratio and the fractional excretion of sodium were normal. The mean beta-2 microglobulin/creatinine ratio was 278.8 μg/g, and it was abnormally high in 2 patients. The mean tubular phosphorus reabsorption was 92.6%; it was abnormally low in 1 patient. Severe kidney or urinary tract involvement was present in 2 patients with recessive dystrophic EB-generalized severe (RDEB-GS): one patient had obstructive bullous lesions in the urethra; the other had end-stage renal disease secondary to focal segmental glomerulosclerosis and was on peritoneal dialysis for 3 years.

Conclusions

Assessment for renal and urinary tract involvement should become a routine part of the evaluation of patients with any type of EB, but especially of patients with RDEB-GS. Patients with mild tubular dysfunction need long-term follow-up to detect early deterioration of renal function.

A Novel Phenotype of Junctional Epidermolysis Bullosa with Transient Skin Fragility and Predominant Ocular Involvement Responsive to Human Amniotic Membrane Eyedrops

Junctional epidermolysis bullosa (JEB) is a clinically and genetically heterogeneous skin fragility disorder frequently caused by mutations in genes encoding the epithelial laminin isoform, laminin-332. JEB patients also present mucosal involvement, including painful corneal lesions. Recurrent corneal abrasions may lead to corneal opacities and visual impairment. Current treatments are merely supportive. We report a novel JEB phenotype distinguished by the complete resolution of skin fragility in infancy and persistent ocular involvement with unremitting and painful corneal abrasions. Biallelic LAMB3 mutations c.3052-5C>G and c.3492_3493delCG were identified as the molecular basis for this phenotype, with one mutation being a hypomorphic splice variant that allows residual wild-type laminin-332 production. The reduced laminin-332 level was associated with impaired keratinocyte adhesion. Then, we also investigated the therapeutic power of a human amniotic membrane (AM) eyedrop preparation for corneal lesions. AM were isolated from placenta donors, according to a procedure preserving the AM biological characteristics as a tissue, and confirmed to contain laminin-332. We found that AM eyedrop preparation could restore keratinocyte adhesion in an in vitro assay. Of note, AM eyedrop administration to the patient resulted in long-lasting remission of her ocular manifestations. Our findings suggest that AM eyedrops could represent an effective, non-invasive, simple-to-handle treatment for corneal lesions in patients with JEB and possibly other EB forms.

Epidermolysis Bullosa in Spain: Observational Study of a Cohort of Patients Treated in a National Referral Center

BACKGROUND AND OBJECTIVE

Epidermolysis bullosa (EB) is a heterogeneous group of inherited disorders characterized by a high degree of mucocutaneous fragility. This study aimed to describe the clinical and epidemiologic characteristics of patients with EB treated in Hospital Universitario La Paz, a national referral center for inherited EB.

MATERIAL AND METHODS

Observational, retrospective, single-center study. We included all cases with a clinical and molecular diagnosis of EB managed in the hospital's dermatology department from January 2, 2000, to February 28, 2021.

RESULTS

A total of 214 cases were studied. The median (interquartile range) age was 17 (8-32) years; 54.2% were women. One hundred thirty-five (63.1%) patients had dystrophic EB, 67 (31.3%) had EB simplex, 8 (3.7%) had junctional EB, and 3 (1.4%) had Kindler syndrome. One (0.5%) had EB acquisita. Over a third (35.5%) of the patients resided in Madrid. The most common clinical complications were pruritus (63.1%), local infections (56.5%), and pain (54.7%). The most serious ones were cardiomyopathy (in 5.6%) and squamous cell carcinoma (10.3%). Twenty-two patients (10.3%) died.

CONCLUSIONS

Dystrophic EB was the most prevalent clinical form. The most prevalent complications were pruritus, pain, and infections. The most serious ones were cardiomyopathy and squamous cell carcinoma. This study is the first in Spain that explores strategies for improving the health status and quality of life of patients with EB.

Personalized Development of Antisense Oligonucleotides for Exon Skipping Restores Type XVII Collagen Expression in Junctional Epidermolysis Bullosa

Intermediate junctional epidermolysis bullosa caused by mutations in the COL17A1 gene is characterized by the frequent development of blisters and erosions on the skin and mucous membranes. The rarity of the disease and the heterogeneity of the underlying mutations renders therapy developments challenging. However, the high number of short in-frame exons facilitates the use of antisense oligonucleotides (AON) to restore collagen 17 (C17) expression by inducing exon skipping. In a personalized approach, we designed and tested three AONs in combination with a cationic liposomal carrier for their ability to induce skipping of COL17A1 exon 7 in 2D culture and in 3D skin equivalents. We show that AON-induced exon skipping excludes the targeted exon from pre-mRNA processing, which restores the reading frame, leading to the expression of a slightly truncated protein. Furthermore, the expression and correct deposition of C17 at the dermal-epidermal junction indicates its functionality. Thus, we assume AON-mediated exon skipping to be a promising tool for the treatment of junctional epidermolysis bullosa, particularly applicable in a personalized manner for rare genotypes.

Intravenous allogeneic umbilical cord blood-derived mesenchymal stem cell therapy in recessive dystrophic epidermolysis bullosa patients

BACKGROUND

Recessive dystrophic epidermolysis bullosa (RDEB) is an incurable disease that causes severe mucocutaneous fragility due to mutations in COL7A1 (encoding type VII collagen [C7]). In this phase I/IIa trial, we evaluated the safety and possible clinical efficacy of intravenous infusion of allogeneic human umbilical cord blood–derived mesenchymal stem cells (hUCB-MSCs) in patients with RDEB.

METHODS

Four adult and two pediatric patients with RDEB were treated with 3 intravenous injections of hUCB-MSCs (1 × 10⁶ to 3 × 10⁶ cells/kg) every 2 weeks and followed up for 8–24 months after treatment. The primary endpoint was safety. Secondary endpoints related to efficacy included clinical parameters, such as disease severity score, wound assessment, itch and pain score, and quality of life. C7 expression levels and inflammatory infiltrates in the skin, as well as serum levels of inflammatory markers and neuropeptides, were also assessed.

RESULTS

Intravenous hUCB-MSC infusions were well tolerated, without serious adverse events. Improvements in the Birmingham Epidermolysis Bullosa Severity Score, body surface area involvement, blister counts, pain, pruritus, and quality of life were observed with maximal effects at 56–112 days after treatment. hUCB-MSC administration induced M2 macrophage polarization and reduced mast cell infiltration in RDEB skin. Serum levels of substance P were decreased after therapy. Increased C7 expression was observed at the dermoepidermal junction in 1 of 6 patients at day 56.

CONCLUSION

To the best of our knowledge, this is the first clinical trial of systemic administration of allogeneic hUCB-MSCs in patients with RDEB, demonstrating safety and transient clinical benefits.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04520022.

FUNDING

This work was supported by Daewoong Pharmaceutical Co. Ltd. and Kangstem Biotech Co. Ltd.

Supporting sexuality for people living with epidermolysis bullosa: clinical practice guidelines

This article presents evidence-based Clinical Practice Guidelines (CPG) for the provision of healthcare services to address sexuality for people living with epidermolysis bullosa (EB). Currently, a lack of EB-specific research limits these services to sexual health assessment and intervention strategies designed for the general population. Due to the unique challenges of EB, a rare skin-fragility condition causing blistering responses to minor skin trauma and other systemic and secondary complications, condition-specific strategies are needed to support people with EB in achieving valued sexual lifestyles. This CPG represents the work of an international panel comprised of thirteen members including a medical doctor, nurses, psychologists, a social worker, an occupational therapist, and patient population involvement members living with EB. It describes the development of EB-specific recommendations for two primary domains of assessment and intervention related to sexuality: psychosocial and mechanical. Following a rigorous evidence-based guideline development process, this CPG establishes the first internationally actionable clinical practice recommendations for sexuality-related assessment and intervention for this population. Future research priorities are identified. Supplemental materials included provide additional support to clinicians in developing the necessary understanding and skills to promote equity and efficacy in this care domain.

Beneficial Effect of Systemic Allogeneic Adipose Derived Mesenchymal Cells on the Clinical, Inflammatory and Immunologic Status of a Patient With Recessive Dystrophic Epidermolysis Bullosa: A Case Report

Recessive dystrophic epidermolysis bullosa (RDEB) is an incurable inherited mucocutaneous fragility disorder characterized by recurrent blisters, erosions, and wounds. Continuous blistering triggers overlapping cycles of never-ending healing and scarring commonly evolving to chronic systemic inflammation and fibrosis. The systemic treatment with allogeneic mesenchymal cells (MSC) from bone marrow has previously shown benefits in RDEB. MSC from adipose tissue (ADMSC) are easier to isolate. This is the first report on the use of systemic allogeneic ADMSC, correlating the clinical, inflammatory, and immunologic outcomes in RDEB indicating long-lasting benefits. We present the case of an RDEB patient harboring heterozygous biallelic COL7A1 gene mutations and with a diminished expression of C7. The patient presented with long-lasting refractory and painful oral ulcers distressing her quality of life. Histamine receptor antagonists, opioid analgesics, proton-pump inhibitors, and low-dose tricyclic antidepressants barely improved gastric symptoms, pain, and pruritus. Concomitantly, allogeneic ADMSC were provided as three separate intravenous injections of 106 cells/kg every 21 days. ADMSC treatment was well-tolerated. Improvements in wound healing, itch, pain and quality of life were observed, maximally at 6-9 months post-treatment, with the relief of symptoms still noticeable for up to 2 years. Remarkably, significant modifications in PBL participating in both the innate and adaptive responses, alongside regulation of levels of profibrotic factors, MCP-1/CCL2 and TGF-β, correlated with the health improvement. This treatment might represent an alternative for non-responding patients to conventional management. It seems critical to elucidate the paracrine modulation of the immune system by MSC for their rational use in regenerative/immunoregulatory therapies.

Translational perspectives to treat Epidermolysis bullosa-Where do we stand?

Epidermolysis bullosa (EB) is the prototypical example of genetic skin fragility disorders. Genotypic heterogeneity, modifier genes, epigenetic, biochemical and environmental factors alter and determine pathogenic traits and, ultimately, the wide and striking phenotypic variability in EB. Besides the primary structural-functional defect, chronic tissue damage with induction and dysregulation of inflammatory pathways is a common pathogenic mechanism in EB. In localized variants, the inflammatory aberrations may mainly affect the micromilieu of lesional skin, while a systemic inflammatory response was shown to contribute to the systemic morbidity in severe EB subtypes with extensive cutaneous involvement. Our continued understanding of the pathophysiology of EB, as well as advances in molecular technologies, has paved the way for translational therapeutic approaches. The spectrum comprises of corrective and symptom-relieving therapies that include innovative therapeutic options garnered from the bench, repurposed drugs approved for other diseases, as well as strategies for gene-, protein- and cell-based therapies. Immunological traits further define new targets of therapy, aimed at improving skin barrier restoration, microbial surveillance and infection control, wound healing and anti-neoplastic effects. Clinical availability and feasibility of these approaches for all EB patients and subtypes are currently limited, reflecting issues of efficacy, specificity, tolerability and safety. A multistep targeting approach and highly individualized, risk-stratified combinatory treatment plans will thus be essential for sustained efficacy and improved overall quality of life in EB.

Epidermolysis bullosa

Epidermolysis bullosa (EB) is an inherited, heterogeneous group of rare genetic dermatoses characterized by mucocutaneous fragility and blister formation, inducible by often minimal trauma. A broad phenotypic spectrum has been described, with potentially severe extracutaneous manifestations, morbidity and mortality. Over 30 subtypes are recognized, grouped into four major categories, based predominantly on the plane of cleavage within the skin and reflecting the underlying molecular abnormality: EB simplex, junctional EB, dystrophic EB and Kindler EB. The study of EB has led to seminal advances in our understanding of cutaneous biology. To date, pathogenetic mutations in 16 distinct genes have been implicated in EB, encoding proteins influencing cellular integrity and adhesion. Precise diagnosis is reliant on correlating clinical, electron microscopic and immunohistological features with mutational analyses. In the absence of curative treatment, multidisciplinary care is targeted towards minimizing the risk of blister formation, wound care, symptom relief and specific complications, the most feared of which - and also the leading cause of mortality - is squamous cell carcinoma. Preclinical advances in cell-based, protein replacement and gene therapies are paving the way for clinical successes with gene correction, raising hopes amongst patients and clinicians worldwide.

Anterior-segment spectral domain optical coherence tomography in epidermolysis bullosa

PURPOSE

Assess epidermolysis bullosa (EB)-related corneal pathology using anterior segment optical coherence tomography (AS-OCT) and correlate imaging with clinical metrics in EB patients versus age-matched controls.

METHODS

EB patients and controls were recruited during an EB conference (July 2018) and at Tufts Medical Center (June-August 2019). Subjects completed a questionnaire, had best corrected visual acuity (BCVA) tested, and underwent AS-OCT scanning. Stromal and epithelial thickness were measured. Depth, length, and type of the three largest lesions were assessed by a masked examiner using a novel pathology grading system. Multivariate analysis of AS-OCT findings and clinical metrics was performed.

RESULTS

62 EB patients and 60 age-matched controls were enrolled. Mean BCVA was 1.8 lines worse in patients (p < 0.001). Vision loss was associated with increased stromal thickness. Discrete lesions were seen in 60.2% of patient eyes, averaging 1.71 ± 1.75 lesions in patients and 0.14 ± 0.42 in controls (p < 0.001). Mean primary lesion depth was 151.88 ± 97.49 μm in patients. Patients showed significant stromal thickening versus controls and lesions were most common in the periphery and inferiorly. Differences in frequency and duration of abrasions and severity of pain were all statistically and clinically significant in patients versus controls (p < 0.001).

CONCLUSIONS

AS-OCT can visualize and quantify differences in the corneas of EB patients compared with age-matched controls. Novel findings include quantification of average depth, length, and severity of discrete lesions, and sparing of the superior quadrant from stromal thickening in EB patients. These results support use of AS-OCT and a questionnaire in clinical trials for new EB therapies.

EB (epidermolysis bullosa)-House Austria: Pioneering work for the care of patients with rare diseases

The care of patients with epidermolysis bullosa (EB) poses a major challenge due to the rarity, heterogeneity and complexity of the disease as well as the occurrence of numerous primary and secondary extracutaneous manifestations, causing a significant morbidity and mortality. Specialized treatment centers are essential for offering these patients adequate care, including individual, interdisciplinary coordinated treatments according to current medical standards, and access to innovative therapeutic options. Against this background, the EB House Austria was founded in 2005 and designated the first national center of expertise for genodermatoses with a focus on EB in 2017. In the same year, it became a member of the European Reference Network for Rare Skin Diseases (ERN Skin). The pillars of this institution (outpatient clinic, research unit, academy, clinical study center) interact closely with each other, with numerous national and international clinical and scientific partners, as well as with patients and their relatives via the DEBRA Austria patient group. The development of the EB House Austria as a reference center is characterized by a long-term pioneering work, which in turn could pave the way for the optimization of care for comparable diseases as well as general care structures.

Consensus reclassification of inherited epidermolysis bullosa and other disorders with skin fragility

BACKGROUND

Several new genes and clinical subtypes have been identified since the publication in 2014 of the report of the last International Consensus Meeting on Epidermolysis Bullosa (EB).

OBJECTIVES

We sought to reclassify disorders with skin fragility, with a focus on EB, based on new clinical and molecular data.

METHODS

This was a consensus expert review.

RESULTS

In this latest consensus report, we introduce the concept of genetic disorders with skin fragility, of which classical EB represents the prototype. Other disorders with skin fragility, where blisters are a minor part of the clinical picture or are not seen because skin cleavage is very superficial, are classified as separate categories. These include peeling skin disorders, erosive disorders, hyperkeratotic disorders, and connective tissue disorders with skin fragility. Because of the common manifestation of skin fragility, these 'EB-related' disorders should be considered under the EB umbrella in terms of medical and socioeconomic provision of care.

CONCLUSIONS

The proposed classification scheme should be of value both to clinicians and researchers, emphasizing both clinical and genetic features of EB. What is already known about this topic? Epidermolysis bullosa (EB) is a group of genetic disorders with skin blistering. The last updated recommendations on diagnosis and classification were published in 2014. What does this study add? We introduce the concept of genetic disorders with skin fragility, of which classical EB represents the prototype. Clinical and genetic aspects, genotype-phenotype correlations, disease-modifying factors and natural history of EB are reviewed. Other disorders with skin fragility, e.g. peeling skin disorders, erosive disorders, hyperkeratotic disorders, and connective tissue disorders with skin fragility are classified as separate categories; these 'EB-related' disorders should be considered under the EB umbrella in terms of medical and socioeconomic provision of care. Linked Comment: Pope. Br J Dermatol 2020; 183:603.

Phase I/II open-label trial of intravenous allogeneic mesenchymal stromal cell therapy in adults with recessive dystrophic epidermolysis bullosa

BACKGROUND

Recessive dystrophic epidermolysis bullosa (RDEB) is a hereditary blistering disorder due to a lack of type VII collagen. At present, treatment is mainly supportive.

OBJECTIVES

To determine whether intravenous allogeneic bone marrow-derived mesenchymal stromal/stem cells (BM-MSCs) are safe in RDEB adults and if the cells improve wound healing and quality of life.

METHODS

We conducted a prospective, phase I/II, open-label study recruiting 10 RDEB adults to receive 2 intravenous infusions of BM-MSCs (on day 0 and day 14; each dose 2-4 × 10⁶ cells/kg).

RESULTS

BM-MSCs were well tolerated with no serious adverse events to 12 months. Regarding efficacy, there was a transient reduction in disease activity scores (8/10 subjects) and a significant reduction in itch. One individual showed a transient increase in type VII collagen.

LIMITATIONS

Open-label trial with no placebo.

CONCLUSIONS

MSC infusion is safe in RDEB adults and can have clinical benefits for at least 2 months.

Epidermolysis Bullosa-Associated Squamous Cell Carcinoma: From Pathogenesis to Therapeutic Perspectives

Epidermolysis bullosa (EB) is a heterogeneous group of inherited skin disorders determined by mutations in genes encoding for structural components of the cutaneous basement membrane zone. Disease hallmarks are skin fragility and unremitting blistering. The most disabling EB (sub)types show defective wound healing, fibrosis and inflammation at lesional skin. These features expose patients to serious disease complications, including the development of cutaneous squamous cell carcinomas (SCCs). Almost all subjects affected with the severe recessive dystrophic EB (RDEB) subtype suffer from early and extremely aggressive SCCs (RDEB-SCC), which represent the first cause of death in these patients. The genetic determinants of RDEB-SCC do not exhaustively explain its unique behavior as compared to low-risk, ultraviolet-induced SCCs in the general population. On the other hand, a growing body of evidence points to the key role of tumor microenvironment in initiation, progression and spreading of RDEB-SCC, as well as of other, less-investigated, EB-related SCCs (EB-SCCs). Here, we discuss the recent advances in understanding the complex series of molecular events (i.e., fibrotic, inflammatory, and immune processes) contributing to SCC development in EB patients, cross-compare tumor features in the different EB subtypes and report the most promising therapeutic approaches to counteract or delay EB-SCCs.

Management of epidermolysis bullosa simplex in pregnancy: A case report

Epidermolysis bullosa (EB) encompasses a group of diseases characterized by extreme fragility of skin and mucous membranes, resulting in blister formation following minimal injury. There are 4 types of EB, with epidermolysis bullosa simplex (EBS) being the most common. We report our experience with the care of a parturient woman diagnosed with EBS. There is little literature on pregnancy in women with this condition. Special precautions are necessary during diagnostic and therapeutic interventions to avoid bullae formation or exacerbation of existing lesions. Frictional or shearing forces are typically more damaging than compressive forces. Multidisciplinary planning was done for our patient to ensure uneventful labor and delivery. Elective induction of labor was started at 40 weeks of gestation. She eventually underwent a cesarean delivery after failed trial of labor. We present this case to highlight the obstetric and anesthetic implications of caring for a parturient with EBS.

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Blister formation occurs following minimal injury in epidermolysis bullosa.

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Frictional or shearing forces rather than direct pressure predispose to bullae.

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Use of adhesive materials should be avoided during patient care.

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Vaginal delivery without instrumentation is preferred for pregnant women with epidermolysis bullosa.

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If cesarean delivery is necessary, neuraxial anesthesia is preferred to general anesthesia.

Natural Exon Skipping Sets the Stage for Exon Skipping as Therapy for Dystrophic Epidermolysis Bullosa

Dystrophic epidermolysis bullosa (DEB) is a devastating blistering disease affecting skin and mucous membranes. It is caused by pathogenic variants in the COL7A1 gene encoding type VII collagen, and can be inherited dominantly or recessively. Recently, promising proof-of-principle has been shown for antisense oligonucleotide (AON)-mediated exon skipping as a therapeutic approach for DEB. However, the precise phenotypic effect to be anticipated from exon skipping, and which patient groups could benefit, is not yet clear. To answer these questions, we studied new clinical and molecular data on seven patients from the Dutch EB registry and reviewed the literature on COL7A1 exon skipping variants. We found that phenotypes associated with dominant exon skipping cannot be distinguished from phenotypes caused by other dominant DEB variants. Recessive exon skipping phenotypes are generally relatively mild in the spectrum of recessive DEB. Therefore, for dominant DEB, AON-mediated exon skipping is unlikely to ameliorate the phenotype. In contrast, the overall severity of phenotypes associated with recessive natural exon skipping pivots toward the milder end of the spectrum. Consequently, we anticipate AON-mediated exon skipping for recessive DEB caused by bi-allelic null variants should lead to a clinically relevant improvement of this devastating phenotype.

Clinical practice guidelines for laboratory diagnosis of epidermolysis bullosa

Linked Comment: https://doi.org/10.1111/bjd.18377.

https://doi.org/10.1111/bjd.18829 available online

Resting Energy Expenditure and Protein Balance in People with Epidermolysis Bullosa

Epidermolysis bullosa (EB) is a group of conditions characterized by severe fragility of the skin that causes recurring blistering. The recessive dystrophic subtype of EB (RDEB) has a strong impact on the nutritional status. We evaluated the resting energy expenditure (REE) and presence of protein catabolism in patients with RDEB. REE was assessed in 10 subjects (7 females; age range 4-33 years) by indirect calorimetry and using a predictive equation. Nitrogen balance was calculated by protein intake and 24 h urinary urea excretion estimations. An assessment of body surface area (BSA) with infected and non-infected skin lesions was applied to the nitrogen balance burn equation that was adapted to EB. The REE values predicted by the equation were consistently lower than the ones measured, except for two subjects. All subjects recorded high protein and energy intake, with protein intake being higher than 4 g protein/kg/day for five subjects. Even so, protein catabolism was observed in six subjects, three of whom had infected wounds. This study raises the hypothesis that the clinical and nutritional risks of people with RDEB are associated with an increased REE and negative nitrogen balance, which reinforces the importance of nutritional support.

Laryngeal lesion associated with epidermolysis bullosa secondary to congenital plectin deficiency

INTRODUCTION

Epidermolysis bullosa (EB) is a congenital disease characterized by fragility of epithelial structures. The skin is the organ primarily affected, resulting in the formation of skin blisters. Some forms of EB may also present mucosal lesions.

CASE REPORT

We report the case of a girl with epidermolysis bullosa simplex (EBS) associated with muscular dystrophy secondary to congenital plectin deficiency. She presented severe respiratory tract lesions extending from the oral cavity to the larynx. In particular, we describe our medical and surgical management of the laryngeal lesions, responsible for several episodes of respiratory distress and feeding difficulties.

DISCUSSION

Epidermolysis bullosa simplex associated with muscular dystrophy is a rare hereditary form of EB, as fewer than 50 cases have been reported in the literature. This form is characterized by mucosal lesions involving the upper aerodigestive tract, with consequences for feeding, phonation and breathing. Special care must be taken when performing diagnostic and therapeutic procedures to avoid worsening the lesions of this very fragile mucosa. Tracheotomy is a harmful procedure in these patients and should only be considered as a last resort.

A nutrition-based approach to epidermolysis bullosa: Causes, assessments, requirements and management

Inherited epidermolysis bullosa (EB) is a clinically and genetically heterogeneous group of rare diseases characterized by skin and mucous membrane fragility. EB primarily involves the skin and, in specific subtypes, the mucous membrane, resulting in complications which can strongly affect nutritional status (e.g. gastrointestinal complications, hand deformities, pain). The aims of nutritional support mainly include improving nutritional status, alleviating the stress of oral feeding and minimizing nutritional deficiencies, thus consequently improving growth, pubertal development, bowel function, immune status and wound healing. The aim of this review is to discuss knowledge of different aspects of the disease related to nutrition and growth.

Phenotypic Spectrum of Epidermolysis Bullosa: The Paradigm of Syndromic versus Non-Syndromic Skin Fragility Disorders

The heritable forms of epidermolysis bullosa (EB), a phenotypically heterogeneous group of skin fragility disorders, is currently associated with mutations in as many as 21 distinct genes. EB is primarily a disorder affecting the epithelial layers of skin and mucous membranes, without extracutaneous manifestations, and thus is nonsyndromic. However, recent demonstrations of skin blistering in multisystem disorders with single gene defects highlight the concept of syndromic EB. Here, we review the phenotypic and genotypic features of syndromic forms of EB to delineate the concept of syndromic versus nonsyndromic skin fragility disorders.

A review of scoring systems for ocular involvement in chronic cutaneous bullous diseases

BACKGROUND

Epidermolysis bullosa (EB) and autoimmune blistering diseases (AIBD) describe a group of rare chronic dermatoses characterized by cutaneous fragility and blistering. Although uncommon, significant ocular surface disease (OSD) may occur in both and require ophthalmological assessment. Disease scoring systems have a critical role in providing objective and accurate assessment of disease severity. The objectives of this report were, firstly, to document the prevalence and severity of ocular involvement in EB/AIBD. Secondly, to review and evaluate existing ocular and systemic scoring systems for EB/AIBD. Finally, to identify areas where further development of ocular specific tools in EB/AIBD could be pursued.

METHODS

A literature search was performed in October 2017 utilising Medline, Embase, and Scopus databases. The results were restricted by date of publication, between 01.01.1950 and 31.10.2017. The reference lists of these articles were then reviewed for additional relevant publications. Articles of all languages were included if an English translation was available. Articles were excluded if they were duplicates, had no reference to ocular involvement in EB/AIBD or described ocular involvement in other diseases.

RESULTS

Descriptions of ocular involvement in EB/AIBD were identified in 88 peer-reviewed journal articles. Findings reported include but are not limited to: cicatrising conjunctivitis, meibomian gland dysfunction, dry eye disease, trichiasis, symblepharon, fornix fibrosis, keratopathy, ectropion/entropion, ankyloblepharon, corneal ulceration, visual impairment and blindness. Although scoring systems exist for assessment of OSD in mucous membrane pemphigoid, no such tools exist for the other AIBD subtypes or for EB. Several systemic scoring systems exist in the dermatological literature that are efficacious in grading overall EB/AIBD severity, but have limited inclusion of ocular features. To the best of our knowledge, there is no recognised or validated scoring systems which comprehensively stages or grades the spectrum of ocular manifestations in EB/AIBD.

CONCLUSIONS

There are a range of ocular complications documented in EB and AIBD. Development of a comprehensive ocular scoring system for EB/AIBD which incorporates the delineation between 'activity' and 'damage' would facilitate more objective patient assessment, improved longitudinal monitoring, comparison of intervention outcomes, and provide commonality for discussion of these patients due to the multidisciplinary nature of their care.

Toll-like receptor signalling induces the expression of serum amyloid A in epidermal keratinocytes and dermal fibroblasts

BACKGROUND

Toll-like receptors (TLRs) play critical roles in innate immune response by sensing pathogen- or damage-associated molecular patterns. Epidermal keratinocytes and dermal fibroblasts also produce proinflammatory cytokines and chemokines under stimulation with TLR ligands. Serum amyloid A (SAA) is an essential factor in the pathogenesis of secondary amyloidosis, and also has immunomodulatory functions. SAA are produced mainly by hepatocytes but also by a variety of cells, including immune cells, endothelial cells, synoviocytes, and epidermal keratinocytes. However, SAA expression in human dermal fibroblasts has not been shown to date.

AIM

To investigate the effect of TLR ligands on SAA expression in epidermal keratinocytes and dermal fibroblasts.

METHODS

We investigated whether TLR ligands induce the expression of SAA in normal human epidermal keratinocytes (NHEKs) and normal human dermal fibroblasts (NHDFs) by real-time quantitative PCR and ELISA. The effect of SAA on its own expression in NHDFs was also studied.

RESULTS

SAA expression was induced via nuclear factor-κB by TLR1/2, 3, 5 and 2/6 ligands in NHEKs. In NHDFs, TLR1/2 and TLR2/6 ligands increased SAA expression. SAA further induced its own expression via TLR1/2 and NF-κB in NHDFs, as previously reported for NHEKs.

CONCLUSIONS

Our results provide new evidence that the skin's innate immune response contributes to the production of SAA, which might lead to an increased risk of systemic complications such as secondary amyloidosis of recessive dystrophic epidermolysis bullosa.

Update on Genetic Conditions Affecting the Skin and the Kidneys

Genetic conditions affecting the skin and kidney are clinically and genetically heterogeneous, and target molecular components present in both organs. The molecular pathology involves defects of cell-matrix adhesion, metabolic or signaling pathways, as well as tumor suppressor genes. This article gives a clinically oriented overview of this group of disorders, highlighting entities which have been recently described, as well as the progress made in understanding well-known entities. The genetic bases as well as molecular cell biological mechanisms are described, with therapeutic applications.

The role of TGFβ in wound healing pathologies

Wound healing is one of the most complex processes in multicellular organisms, involving numerous intra- and intercellular signalling pathways in various cell types. It involves extensive communication between the cellular constituents of diverse skin compartments and its extracellular matrix. Miscommunication during healing may have two distinct damaging consequences: the development of a chronic wound or the formation of a hypertrophic scar/keloid. Chronic wounds are defined as barrier defects that have not proceeded through orderly and timely reparation to regain structural and functional integrity. Several growth factors are involved in wound healing, of which transforming growth factor beta (TGFβ) is of particular importance for all phases of this procedure. It exerts pleiotropic effects on wound healing by regulating cell proliferation, differentiation, extracellular matrix production, and modulating the immune response. In this review we are presenting the role of TGFβ in physiological and pathological wound healing. We show that the context-dependent nature of the TGFβ signaling pathways on wound healing is the biggest challenge in order to gain a therapeutically applicable comprehensive knowledge of their specific involvement in chronic wounds.

Recessive mutation in tetraspanin CD151 causes Kindler syndrome-like epidermolysis bullosa with multi-systemic manifestations including nephropathy

Epidermolysis bullosa (EB) is caused by mutations in as many as 19 distinct genes. We have developed a next-generation sequencing (NGS) panel targeting genes known to be mutated in skin fragility disorders, including tetraspanin CD151 expressed in keratinocytes at the dermal-epidermal junction. The NGS panel was applied to a cohort of 92 consanguineous families of unknown subtype of EB. In one family, a homozygous donor splice site mutation in CD151 (NM_139029; c.351+2T>C) at the exon 5/intron 5 border was identified, and RT-PCR and whole transcriptome analysis by RNA-seq confirmed deletion of the entire exon 5 encoding 25 amino acids. Immunofluorescence of proband's skin and Western blot of skin proteins with a monoclonal antibody revealed complete absence of CD151. Transmission electron microscopy showed intracellular disruption and cell-cell dysadhesion of keratinocytes in the lower epidermis. Clinical examination of the 33-year old proband, initially diagnosed as Kindler syndrome, revealed widespread blistering, particularly on pretibial areas, poikiloderma, nail dystrophy, loss of teeth, early onset alopecia, and esophageal webbing and strictures. The patient also had history of nephropathy with proteinuria. Collectively, the results suggest that biallelic loss-of-function mutations in CD151 underlie an autosomal recessive mechano-bullous disease with systemic features. Thus, CD151 should be considered as the 20th causative, EB-associated gene.

Imaging findings in systemic childhood diseases presenting with dermatologic manifestations

PURPOSE

Many childhood diseases often present with skin abnormalities with which radiologists are largely unfamiliar. Knowledge of associated dermatologic manifestations may aid the radiologist in confirming the diagnosis and recommending targeted imaging of affected organs.

METHODS

We review the imaging findings in childhood diseases associated with dermatologic manifestations.

FINDINGS

Diseases include dermatologic findings which herald underlying malignancy (Neuroblastoma, leukemia/lymphoma, Langerhans cell histiocytosis),are associated with risk of malignancy (Epidermolysis Bullosa, basal cell nevus syndrome, Cowden's syndrome, Tuberous Sclerosis),or indicate a systemic inflammatory/immune disorder (Kawasaki's disease, Henoch Schonlein Purpura, systemic lupus erythematosus, scleroderma, sarcoidosis, dermatomyositis and immune thrombocytopenic purpura).

CONCLUSION

Familiarity with pertinent findings in childhood diseases presenting with dermatologic manifestations in childhood diseases aids the radiologist in confirming the diagnosis and guiding imaging workup.

Pain in Patients with Dystrophic Epidermolysis Bullosa: Association with Anxiety and Depression

OBJECTIVE

We investigate the presence and the quality of pain in patients with dystrophic epidermolysis bullosa (DEB), and its correlation with the level of anxiety and depression.

METHODS

We collected data from 27 DEB patients and 26 healthy individuals. DEB patients and controls completed 1 scale for the quality of pain, and 1 scale for anxiety and depression. Pain was assessed with the short form of the McGill Pain Questionnaire, whereas anxiety and depression were assessed with the Hamilton rating scale for anxiety and depression.

RESULTS

DEB patients and healthy control individuals were homogeneous for age and gender (p>0.05). A statistically significant difference in the two groups was seen for sensory pain rating scale (p<0.001), affective pain rating scale (p=0.029), total pain rating scale (p<0.001), visual analogue scale (p=0.012) and present pain intensity (p=0.001), but not for anxiety (p=0.169) and depression (p=0.530). The characteristics of pain that showed a significant difference between DEB patients and healthy controls were shooting, splitting, tender and throbbing (p<0.05). In DEB patients pain was not correlated with anxiety or depression (p>0.05), whereas a slight correlation between pain and anxiety was found in healthy controls (p<0.05). No difference was found between quality of pain and anxiety-depression in DEB patients (p>0.05), but was between the DEB dominant and the recessive form of DEB (p=0.025).

CONCLUSION

The perception of pain in DEB patients appears greater than in healthy individuals, with splitting and tender characteristics being the most significant ones, but was not associated with anxious and/or depressive symptoms.

Hemidesmosome integrity protects the colon against colitis and colorectal cancer

OBJECTIVE

Epidemiological and clinical data indicate that patients suffering from IBD with long-standing colitis display a higher risk to develop colorectal high-grade dysplasia. Whereas carcinoma invasion and metastasis rely on basement membrane (BM) disruption, experimental evidence is lacking regarding the potential contribution of epithelial cell/BM anchorage on inflammation onset and subsequent neoplastic transformation of inflammatory lesions. Herein, we analyse the role of the α6β4 integrin receptor found in hemidesmosomes that attach intestinal epithelial cells (IECs) to the laminin-containing BM.

DESIGN

We developed new mouse models inducing IEC-specific ablation of α6 integrin either during development (α6^ΔIEC) or in adults (α6^ΔIEC-TAM).

RESULTS

Strikingly, all α6^ΔIEC mutant mice spontaneously developed long-standing colitis, which degenerated overtime into infiltrating adenocarcinoma. The sequence of events leading to disease onset entails hemidesmosome disruption, BM detachment, IL-18 overproduction by IECs, hyperplasia and enhanced intestinal permeability. Likewise, IEC-specific ablation of α6 integrin induced in adult mice (α6^ΔIEC-TAM) resulted in fully penetrant colitis and tumour progression. Whereas broad-spectrum antibiotic treatment lowered tissue pathology and IL-1β secretion from infiltrating myeloid cells, it failed to reduce Th1 and Th17 response. Interestingly, while the initial intestinal inflammation occurred independently of the adaptive immune system, tumourigenesis required B and T lymphocyte activation.

CONCLUSIONS

We provide for the first time evidence that loss of IECs/BM interactions triggered by hemidesmosome disruption initiates the development of inflammatory lesions that progress into high-grade dysplasia and carcinoma. Colorectal neoplasia in our mouse models resemble that seen in patients with IBD, making them highly attractive for discovering more efficient therapies.

[Mucosal manifestations of epidermolysis bullosa : Clinical presentation and management]

Mucosal lesions occur with different prevalence and severity in all subtypes of hereditary epidermolysis bullosa (EB), a group of rare genodermatoses. They are associated with increased morbidity and mortality, especially in severe junctional and dystrophic subtypes. Despite progress in clinical approaches to curative therapy, the management of these patients is still primarily symptom-oriented. Current recommendations mainly rely on expert opinion and experience from health care professionals of specialized centers, since the rarity of this disease largely limits the availability and feasibility of randomized controlled trials. Accurate preventive and supportive care measures, however, can significantly lessen symptoms, avoid/ameliorate complications, and enhance the quality of life of these patients.