Epidermolysis bullosa pruriginosa: dystrophic epidermolysis bullosa with distinctive clinicopathological features

Dominant dystrophic epidermolysis bullosa is associated with glycolytically active GATA3+ T helper 2 cells which may contribute to pruritus in lesional skin

BACKGROUND

Dominant dystrophic epidermolysis bullosa (DDEB) is characterized by trauma-induced blisters and, in some individuals, intense pruritus. Precisely what causes itch in DDEB and optimal ways to reduce it have not been fully determined.

OBJECTIVES

To characterize DDEB skin transcriptomes to identify therapeutic targets to reduce pruritus in patients.

METHODS

Using bulk RNA sequencing, we evaluated affected and unaffected skin biopsy samples from six patients with DDEB (all with the very itchy pruriginosa subtype) and four healthy individuals. Single-cell transcriptomes of affected (n = 2) and unaffected (n = 1) DDEB skin and healthy skin (n = 2) were obtained. Dupilumab treatment was provided for three patients.

RESULTS

The skin bulk transcriptome showed significant enrichment of T helper (Th)1/2 and Th17 pathways in affected DDEB skin compared with nonlesional DDEB skin and healthy skin. Single-cell transcriptomics showed an association of glycolytically active GATA3+ Th2 cells in affected DDEB skin. Treatment with dupilumab in three people with DDEB led to significantly reduced visual analogue scale (VAS) itch scores after 12 weeks (mean VAS 3.83) compared with pretreatment (mean VAS 7.83). Bulk RNAseq and quantitative polymerase chain reaction showed that healthy skin and dupilumab-treated epidermolysis bullosa (EB) pruriginosa skin have similar transcriptomic profiles and reduced Th1/Th2 and Th17 pathway enrichment.

CONCLUSIONS

Single-cell RNAseq helps define an enhanced DDEB-associated Th2 profile and rationalizes drug repurposing of anti-Th2 drugs in treating DDEB pruritus.

Beyond the Surface: A Narrative Review Examining the Systemic Impacts of Recessive Dystrophic Epidermolysis Bullosa

Recessive dystrophic epidermolysis bullosa (RDEB) is a rare genetic disease resulting from inadequate type VII collagen (C7). Although recurrent skin blisters and wounds are the most apparent disease features, the impact of C7 loss is not confined to the skin and mucous membranes. RDEB is a systemic disease marred by chronic inflammation, fibrotic changes, pain, itch, and anemia, significantly impacting QOL and survival. In this narrative review, we summarize these systemic features of RDEB and promising research avenues to address them.

Pruritus Anesis in Dystrophic Epidermolysis Bullosa Pruriginosa with Dupilumab

ABSTRACT

Dystrophic epidermolysis bullosa pruriginosa (DEB-Pr) is a rare subtype of dystrophic epidermolysis bullosa, and traditional treatments have limited efficacy. Dupilumab has demonstrated remarkable efficacy in relieving pruritus. In this case study, after traditional treatment failed, providers recommended the patient begin dupilumab to treat his pruritus. The patient was administrated a loading dose of 600 mg of dupilumab and a dose of 300 mg every 2 weeks. The Dermatology Life Quality Index and Pruritic Numeric Rating Scale were used to assess the patient's situation. After several months, the patient's DEB-Pr was considered in remission. Dupilumab may be a better choice than immunosuppressants for the treatment of pruritus in patients with DEB-Pr.

Genetic diagnosis of a rare COL7A1 variant causing dystrophic epidermolysis bullosa pruriginosa through whole‑exome sequencing

Dystrophic epidermolysis bullosa pruriginosa (DEB-Pr) is a rare subtype of inherited DEB. In the present study, whole-exome sequencing was conducted on 12 individuals from the same affected family and a rare heterozygous variation was identified in the collagen type VII, α1 (COL7A1) gene, namely c.6859G>A (p.Gly2287Arg). Subsequently, this heterozygous variant was confirmed using Sanger sequencing of individual plasma cell-free DNA (cfDNA) and it was demonstrated for the first time, to the best of our knowledge, that COL7A1 exons can be amplified from plasma cfDNA. Within the large pedigree examined, 14 out of 18 individuals carried the variant, 3 carried the wild type, and one exceptional case, III-9, showed no disease symptoms despite carrying the disease variant. A general association between genotype and phenotype was established. Of note, the mutation landscape indicated that this G2287R variant is primarily reported in Asian countries. In silico structure prediction suggested that the residue resulting from the mutation may affect collagen protein stability. In conclusion, the present study provides evidence for the involvement of the COL7A1 G2287R gene variant in the development of DEB-Pr and highlights the potential utility of cfDNA in genetic disease diagnosis.

Itch in recessive dystrophic epidermolysis bullosa: findings of PEBLES, a prospective register study

BACKGROUND

Itch is common and distressing in epidermolysis bullosa (EB) but has not previously been studied in depth in different recessive dystrophic EB (RDEB) subtypes.

OBJECTIVES

As part of a prospective register study of the natural history of RDEB we explored features of itch, medications used, and correlation with disease severity and quality of life.

METHODS

Fifty individuals with RDEB aged 8 years and above completed the Leuven Itch Scale (LIS) (total 243 reviews over a 7-year period). Data included itch frequency, severity, duration, distress, circumstances, consequences, itch surface area and medications for itch. The iscorEB disease severity score and the validated EB quality of life tool, QOLEB, were compared to LIS domains and analysed by RDEB subtype.

RESULTS

Itch was frequent, present in the preceding month in 93% of reviews. Itch severity and distress were significantly greater in severe (RDEB-S) and pruriginosa (RDEB-Pru) subtypes compared to intermediate RDEB (RDEB-I). Itch medications were reported in just over half of reviews including emollients, topical corticosteroids and antihistamines; the proportion of participants not using medication despite frequent pruritus suggests limited efficacy. In inversa RDEB (RDEB-Inv) and RDEB-I, LIS domains correlated with iscorEB and QOLEB. In contrast to previous studies, correlations were lacking in RDEB-S suggesting that global disease burden relatively reduces the contribution of itch.

CONCLUSIONS

This comprehensive study of RDEB-associated itch highlights differences between RDEB subtypes, suggests an unmet need for effective treatments and could serve as control data for future clinical trials incorporating itch as an endpoint.

Epidermolysis Bullosa—A Different Genetic Approach in Correlation with Genetic Heterogeneity

Epidermolysis bullosa is a heterogeneous group of rare genetic disorders characterized by mucocutaneous fragility and blister formation after minor friction or trauma. There are four major epidermolysis bullosa types based on the ultrastructural level of tissue cleavage: simplex, junctional, dystrophic, and Kindler epidermolysis bullosa. They are caused by mutations in genes that encode the proteins that are part of the hemidesmosomes and focal adhesion complex. Some of these disorders can be associated with extracutaneous manifestations, which are sometimes fatal. They are inherited in an autosomal recessive or autosomal dominant manner. This review is focused on the phenomena of heterogeneity (locus, allelic, mutational, and clinical) in epidermolysis bullosa, and on the correlation genotype–phenotype.

Blistering failure of elastic coatings with applications to corrosion resistance

A variety of polymeric surfaces, such as anti-corrosion coatings and polymer-modified asphalts, are prone to blistering when exposed to moisture and air. As water and oxygen diffuse through the material, dissolved species are produced, which generate osmotic pressure that deforms and debonds the coating. These mechanisms are experimentally well-supported; however, comprehensive macroscopic models capable of predicting the formation osmotic blisters, without extensive data-fitting, is scant. Here, we develop a general mathematical theory of blistering and apply it to the failure of anti-corrosion coatings on carbon steel. The model is able to predict the irreversible, nonlinear blister growth dynamics, which eventually reaches a stable state, ruptures, or undergoes runaway delamination, depending on the mechanical and adhesion properties of the coating. For runaway delamination, the theory predicts a critical delamination length, beyond which unstable corrosion-driven growth occurs. The model is able to fit multiple sets of blister growth data with no fitting parameters. Corrosion experiments are also performed to observe undercoat rusting on carbon steel, which yielded trends comparable with model predictions. The theory is used to define three dimensionless numbers which can be used for engineering design of elastic coatings capable of resisting visible deformation, rupture, and delamination.

Dystrophic epidermolysis bullosa pruriginosa: a new case series of a rare phenotype unveils skewed Th2 immunity

BACKGROUND

Dystrophic epidermolysis bullosa pruriginosa (DEB-Pr) is a rare subtype of hereditary epidermolysis bullosa, with a poorly understood pathogenesis and no satisfactory treatment.

OBJECTIVES

To assess the clinical and biological features, genetic basis and therapeutic management, to better characterize this rare genodermatosis.

METHODS

We have conducted a retrospective study, reviewing the clinical presentation, genetic diagnosis, immunohistopathological findings and biological characteristics and management of patients with dystrophic epidermolysis bullosa pruriginosa. This study was conducted in the Department of Dermatology at Saint-Louis Hospital and the Department of Genetics at Necker Hospital (Paris, France). All patients with a diagnosis of DEB-Pr seen between 2010 and 2020 were included.

RESULTS

Seven patients were included, the average age of 50.1 years [range 36-76]. Pruriginous-lichenified papules, plaques or nodules appeared at 27.6 years on average [range 7-66] on pretibial areas and forearms, associated with milia and toenails dystrophy. All patients received multiple treatments, but none could sustainably reduce pruritus. Immunohistopathological analysis of lesion skin revealed subepidermal blister with fibrosis, milia and mast cell infiltration. Serum TNFα, IL1β and IL6 levels were elevated in 2/6 patients. Total serum IgE levels were increased in 7/7 patients, with no history of atopy. Immunophenotyping of circulating T-cells revealed an increased Th2 subset in 4/4 patients, with reduced Th1 and Th17 subpopulations. Genetic analysis of COL7A1 identified 7 distinct causative mutations, six of which were new. Intra-familial clinical variability was documented in 5/7 patients and was associated with the co-inheritance of a recessive COL7A1 mutation or an FLG2 mutation in 2 families.

CONCLUSION

Our study confirms the stereotyped presentation of DEB-Pr with large intra-familial variability in disease expression. Mast cell infiltration, elevated IgE and increased Th2 subset without atopy strongly support a role of Th2-mediated immunity in DEB-Pr, and further argue for new targeted therapeutic options such as dupilumab.

Misdiagnosed dystrophic epidermolysis bullosa pruriginosa: A case report

BACKGROUND

Dystrophic epidermolysis bullosa pruriginosa (DEB-Pr) is a rare subtype of DEB, characterized by recurrent pruritus of the extremities, pruritus papules, nodules, and mossy-like plaques. To date, fewer than 100 cases have been reported. We report a misdiagnosed 30-year-old man with sporadic late-onset DEB-Pr who responded well to tacrolimus treatment, thereby serving as a guide to correct diagnosis and treatment.

CASE SUMMARY

A 30-year-old man presented with recurrent itching plaques of 1-year duration in the left tibia that aggravated and involved both legs and the back. Examination revealed multiple symmetrical, purple, and hyperpigmented papules and nodules with surface exfoliation involving the tibia and dorsum of the neck with negative Nissl's sign, no abnormalities in the skin, mucosa, hair, or fingernail, and no local lymph node enlargement. Blisters were never reported prior to presentation. Serum immunoglobulin E level was 636 IU/mL. Clinical manifestations suggested DEB-Pr. Histological examination showed subepidermal fissure, scar tissue, and milia. Direct immunofluorescence showed no obvious abnormalities. However, we were unable to perform electron microscopy or genetic research following his choice. We treated him with topical tacrolimus. After 2 wk, the itching alleviated, and the skin lesions began to subside. No adverse reactions were observed during treatment.

CONCLUSION

Topical tacrolimus is a safe treatment option for patients with DEB-Pr and can achieve continuous relief of severe itching.

Identification and Computational Analysis of Novel Pathogenic Variants in Pakistani Families with Diverse Epidermolysis Bullosa Phenotypes

Epidermolysis bullosa (EB) includes a group of rare gesnodermatoses that result in blistering and erosions of the skin and mucous membranes. Genetically, pathogenic variants in around 20 genes are known to alter the structural and functional integrity of intraepidermal adhesion and dermo-epidermal anchorage, leading to four different types of EB. Here we report the underlying genetic causes of EB phenotypes segregating in seven large consanguineous families, recruited from different regions of Pakistan. Whole exome sequencing, followed by segregation analysis of candidate variants through Sanger sequencing, identified eight pathogenic variants, including three novel (ITGB4: c.1285G>T, and c.3373G>A; PLEC: c.1828A>G) and five previously reported variants (COL7A1: c.6209G>A, and c.1573C>T; FERMT1: c.676insC; LAMA3: c.151insG; LAMB3: c.1705C>T). All identified variants were either absent or had very low frequencies in the control databases. Our in-silico analyses and 3-dimensional (3D) molecular modeling support the deleterious impact of these variants on the encoded proteins. Intriguingly, we report the first case of a recessively inherited form of rare EBS-Ogna associated with a homozygous variant in the PLEC gene. Our study highlights the clinical and genetic diversity of EB in the Pakistani population and expands the mutation spectrum of EB; it could also be useful for prenatal diagnosis and genetic counseling of the affected families.

Prevalence, pathophysiology and management of itch in epidermolysis bullosa

Epidermolysis bullosa (EB) is a highly diverse group of inherited skin disorders, resulting from mutations in genes encoding proteins of the dermoepidermal junction. Itch (pruritus) is one of the most common symptoms across all EB subtypes. It occurs in blistered or wounded sites, or manifests as a generalized phenomenon, thereby affecting both intact skin and healing wounds. The mechanism of pruritus in EB is unclear. It is likely that skin inflammation secondary to barrier disruption, wound healing cascades and dysregulated activation of epidermal sensory nerve endings are all involved in its pathophysiology on the molecular and cellular level. Understanding these mechanisms in depth is crucial in developing optimized treatments for people with EB and improving quality of life. This review summarizes current evidence on the prevalence, mechanisms and management of itch in EB.

Inherited epidermolysis bullosa: update on the clinical and genetic aspects

Inherited epidermolysis bullosa is a group of genetic diseases characterized by skin fragility and blistering on the skin and mucous membranes in response to minimal trauma. Epidermolysis bullosa is clinically and genetically very heterogeneous, being classified into four main types according to the layer of skin in which blistering occurs: epidermolysis bullosa simplex (intraepidermal), junctional epidermolysis bullosa (within the lamina lucida of the basement membrane), dystrophic epidermolysis bullosa (below the basement membrane), and Kindler epidermolysis bullosa (mixed skin cleavage pattern). Furthermore, epidermolysis bullosa is stratified into several subtypes, which consider the clinical characteristics, the distribution of the blisters, and the severity of cutaneous and extracutaneous signs. Pathogenic variants in at least 16 genes that encode proteins essential for the integrity and adhesion of skin layers have already been associated with different subtypes of epidermolysis bullosa. The marked heterogeneity of the disease, which includes phenotypes with a broad spectrum of severity and many causal genes, hinders its classification and diagnosis. For this reason, dermatologists and geneticists regularly review and update the classification criteria. This review aimed to update the state of the art on inherited epidermolysis bullosa, with a special focus on the associated clinical and genetic aspects, presenting data from the most recent reclassification consensus, published in 2020.

Epidermolysis Bullosa Pruriginosa successfully treated with concomitant topical and systemic agents

Epidermolysis bullosa pruriginosa, a genetic mechanobullous disease, manifests at birth or late in life and is characterised by intense pruritus, resulting in lichenified or nodular prurigo-like lesions and scarring most prominent on the shins. Treatment is unsatisfactory. We report a patient treated with success using a combination of topical and systemic agents.

Promising effect of intravenous immunoglobulin therapy for epidermolysis bullosa pruriginosa

BACKGROUND

Epidermolysis bullosa pruriginosa (EBP) is rare a clinical variant of dystrophic epidermolysis bullosa characterized by trauma-induced bullae formation, milia and nail dystrophy accompanied by severe pruritus. Treatment pruritus of EBP focuses on immunosuppressive treatment with limited efficacy. Treatment strategies are not well-established.

AIM

To provide the genetic characterization of a multi-generational EBP family and discuss the efficacy of intravenous immunoglobulin treatment in EBP.

MATERIALS & METHODS

The clinical characteristics of patients diagnosed with EBP in three consecutive generations were determined. The mutation is analyzed in the index patient's genomic DNA by Sanger sequencing, and this mutation was confirmed in other affected members of the family. Index case with severe phenotype was treated with intravenous immunoglobulin (IVIG).

RESULTS

A heterozygous single nucleotide transition, c.6127G>A, in exon 73 of COL7A1 was identified in all affected members. Physical examination of patients revealed lichenoid papules on extensor surfaces of extremities, excoriations, milia formation and nail dystrophy. Majority of patients had elevated serum IgE levels (%86 (6/7)) without a medical history for atopy. Female patients had generalized involvement and severe phenotype. The skin lesions of the index case were refractory to high dose systemic steroids and cyclosporine treatment. Lesions improved significantly with intravenous immunoglobulin therapy.

CONCLUSION

In severe cases, unresponsive to other therapies, IVIG may be a preferable therapeutic approach to modulate the inflammatory response in patients with EBP.

Epidermolysis bullosa pruriginosa: A rare entity which responded well to thalidomide

Epidermolysis bullosa pruriginosa is an unusual clinical variant of dystrophic epidermolysis bullosa characterized by sublamina densa blistering and intense pruritus leading to hypertrophic lichenoid nodules, plaques, milia, and variable presence of albopapuloid lesions. Most cases are sporadic but a few cases have autosomal dominant or recessive inheritance. Treatment has been quite disappointing and failed to produce satisfactory or sustained results. We report a case of 39-years-old male with epidermolysis bullosa pruriginosa and its response to thalidomide.

Coinheritance of 2 New Potentially Damaging Heterozygous COL7A1 Variants in a Family With Autosomal Dominant Epidermolysis Bullosa Pruriginosa

Epidermolysis bullosa pruriginosa (EBP) is a rare subtype of EB which is characterized by intense pruritus with blistering and nodular or lichenoid lesions most prominent on the lower extremities. It is caused by variants in COL7A1 which encodes for type VII collagen. There is wide phenotypic and genotypic variability between affected individuals. We report 2 potentially pathogenic variants in COL7A1 occurring on the same allele in a family with EBP and autosomal dominant inheritance. Late-onset EBP and incomplete penetrance may lead to delayed presentation in affected family members with the same variants. The broad phenotypic variability seen in EBP suggests that further genotypic and environmental factors may influence presentation. Genetic and histopathological diagnosis is essential, given the considerable overlap with clinically similar presentations such as hypertrophic lichen planus.

Identical COL71A1 heterozygous mutations resulting in different dystrophic epidermolysis bullosa phenotypes

Dystrophic epidermolysis bullosa is a rare blistering condition caused by mutations in the COL7A1 gene. Different clinical variants have been described, with dominant and recessive inheritance, but no consistent findings have been elucidated to establish a genotype-phenotype correlation. We present three unrelated patients with two identical pathogenic compound heterozygous mutations in the COL7A1 gene that developed different clinical forms of dystrophic epidermolysis bullosa-epidermolysis bullosa pruriginosa and mild recessive non-Hallopeau-Siemens-raising the possibility of other genetic or environmental modifying factors responsible for the phenotype of the disease.

Dystrophic epidermolysis bullosa: a review

Dystrophic epidermolysis bullosa is a rare inherited blistering disorder caused by mutations in the COL7A1 gene encoding type VII collagen. The deficiency and/or dysfunction of type VII collagen leads to subepidermal blistering immediately below the lamina densa, resulting in mucocutaneous fragility and disease complications such as intractable ulcers, extensive scarring, malnutrition, and malignancy. The disease is usually diagnosed by immunofluorescence mapping and/or transmission electron microscopy and subsequently subclassified into one of 14 subtypes. This review provides practical knowledge on the disease, including new therapeutic strategies.

Epidermolysis bullosa pruriginosa: a systematic review exploring genotype-phenotype correlation

INTRODUCTION

Epidermolysis bullosa pruriginosa (EBP) is a clinical variant of dystrophic epidermolysis bullosa (DEB), characterized by intense pruritus and hypertrophic, lichenified, prurigo-like papules, plaques, and nodules secondary to scratching. These clinical findings have been attributed to various mutations in the COL7A1 gene. Previous reports have yielded inconsistent findings regarding a possible genotype-phenotype relationship in EBP.

OBJECTIVE

Our aim was to conduct a systematic review aimed at assessing the genotype-phenotype correlation in EBP.

METHODS

A systematic review was conducted using PubMed, Medline, EMBASE, and Cochrane databases for all reports of mutation-verified EBP, published from 1946 to September 2014. Statistical comparison of clinical findings between mutation types was performed using logistic regression analysis.

RESULTS

The review included a total of 28 articles with 74 individuals, which consisted of level 4 non-controlled case series (grade C) and level 5 case reports (grade D). Previous reported mutation types included glycine substitution (GS, 52.7%), in-frame skipping (IFS, 33.8%), non-glycine substitution (NGS, 8.1%), and premature termination codon (PTC, 5.4%). The most common clinical findings were extremities involvement, linear configuration, and nail dystrophy. In comparison with GS mutation carriers, IFS carriers had a higher likelihood of (1) being male (OR 2.99; p = 0.043; 95% CI 1.27-11.4) and (2) presenting with blisters (OR 4.10; p = 0.013; 95% CI 1.34-12.5).

CONCLUSIONS

To our knowledge, this study is the first systematic review examining the relationship between mutation type and clinical presentation in EBP. The findings in this review (1) identify common clinical characteristics of EBP that may help in the assessment of patients with possible EBP; and (2) indicate that certain mutation carriers may have a higher likelihood of exhibiting particular phenotypes. In the case of potential diagnostic challenge, assessment for presence of common clinical findings as well as molecular testing may facilitate correct identification and prognostication.

Epidermolysis Bullosa Pruriginosa

Epidermolysis bullosa (EB) pruriginosa is a rare clinical subtype of dystrophic epidermolysis bullosa (DEB) that is characterized by intense pruritus resulting in hypertrophic, lichenified, prurigo-like plaques and nodules secondary to scratching. The variability in the age of onset, rarity of intact bullae, histologic ambiguities, and close resemblance to other conditions such as acquired inflammatory dermatoses may make diagnosis difficult for this unusual condition, for which fewer than 100 cases have been documented. In this report, we describe 3 cases of EB pruriginosa and review the current literature.

Epidermolysis bullosa pruriginosa: A report of two cases

Epidermolysis bullosa (EB) pruriginosa is a very rare pattern of dystrophic EB caused by type VII collagen gene mutation, with distinctive clinico-pathological features. It is characterized by nodular prurigo-like lichenified lesions, nail dystrophy, and variable presence of albopapuloid lesions. We report two such cases.

Late-onset pretibial recessive dystrophic epidermolysis bullosa

Pretibial epidermolysis bullosa (EB) is a rare form of localized dystrophic EB, characterized by recurrent blistering and scarring plaques occurring predominantly in the pretibial area. In most cases, nail dystrophy, especially of the toenails, is also present. Often there are no clinical abnormalities at birth, and the disorder may only appear after several years. We report a patient who developed symptoms in his fifth decade. Genetic testing identified compound heterozygosity for two pathogenic mutations in the COL7A1 gene. This case highlights a rare variant of mechanobullous disease, and stresses the importance of molecular screening in establishing a correct diagnosis. Precisely why the disorder specifically localizes to the shins or why it may only become apparent in later life is not known.

Epidermolysis bullosa pruriginosa triggered by scabies infestation

Epidermolysis bullosa pruriginosa (EB-Pr) is an unusual variant of dystrophic EB. Potential genetic disease modifiers and metabolic factors have been investigated, but thus far no specific insight into this phenotype has emerged. We report an in-depth description of three patients diagnosed as having EB-Pr in whom this particular phenotype developed after scabies infestation and dramatically improved after full treatment. This short communication suggests that scabies infestation could be one of the important triggering factors for the development of the EB-Pr phenotype.

Epidermolysis bullosa pruriginosa: further clarification of the phenotype

A defect in type VII collagen causes dystrophic epidermolysis bullosa (DEB). The pruriginosa variant (DEB-Pr) is unique because its initial presentation may be delayed until adolescence or adulthood, and its predominant feature is scarring and pruritus without the characteristic skin fragility of DEB. We describe three families with multiple affected members in which DEB-Pr shows an autosomal-dominant inheritance pattern. All affected individuals were examined, and three previously unreported COL7A1 mutations were identified.

An incompletely penetrant novel mutation in COL7A1 causes epidermolysis bullosa pruriginosa and dominant dystrophic epidermolysis bullosa phenotypes in an extended kindred

Epidermolysis bullosa pruriginosa (EBP) is a rare subtype of dystrophic epidermolysis bullosa (DEB) characterized by intense pruritus, nodular or lichenoid lesions, and violaceous linear scarring, most prominently on the extensor extremities. Remarkably, identical mutations in COL7A1, which encodes an anchoring fibril protein present at the dermal-epidermal junction, can cause both DEB and EBP with either autosomal dominant or recessive inheritance. We present one family with both dystrophic and pruriginosa phenotypes of epidermolysis bullosa. The proband is a 19-year-old Caucasian woman who initially presented in childhood with lichenoid papules affecting her extensor limbs and intense pruritus consistent with EBP. Her maternal grandmother saw a dermatologist for similar skin lesions that developed without any known triggers at age 47 and mostly resolved spontaneously after approximately 10 years. The proband's younger brother developed a small crop of pruritic papules on his elbows, dorsal hands, knees, and ankles at age 13. Her second cousin once removed, however, reported a mild blistering disease without pruritus consistent with DEB. Genetic sequencing of the kindred revealed a single dominant novel intron 47 splice site donor G>A mutation, c.4668 + 1 G>A, which we predict leads to exon skipping. Incomplete penetrance is confirmed in her clinically unaffected mother, who carries the same dominant mutation. The wide diversity of clinical phenotypes with one underlying genotype demonstrates that COL7A1 mutations are incompletely penetrant and strongly suggests that other genetic and environmental factors influence clinical presentation.

Skin barrier disruption: a requirement for allergen sensitization?

For at least half a century, noninvasive techniques have been available to quantify skin barrier function, and these have shown that a number of human skin conditions and disorders are associated with defects in skin permeability. In the past decade, several genes responsible for skin barrier defects observed in both monogenetic and complex polygenic disorders have been elucidated and functionally characterized. This has led to an explosion of work in the past 6 years that has identified pathways connecting epidermal barrier disruption and antigen uptake, as well as the quality and/or magnitude of the antigen-specific adaptive immune response. This review will introduce the notion that diseases arise from the dynamic crosstalk that occurs between skin barrier and the immune system using atopic dermatitis or eczema as the disease prototype. Nevertheless, the concepts put forth are highly relevant to a number of antigen-driven disorders for which skin barrier is at least transiently compromised, such as psoriasis, allergic contact dermatitis, and blistering disorders.

Pretibial dystrophic epidermolysis bullosa with localized cutaneous amyloidosis: coincidental or secondary amyloidosis?

Here, we describe the case of a patient with pretibial dystrophic epidermolysis bullosa (PDEB) with amyloid deposition. The patient was a 40-year-old Japanese woman who presented a blistering eruption in the pretibial area with flat violaceous-brown lichenoid papules. The histology of the blister revealed a subepidermal bulla with antibodies bound to basement membrane antigens on the blister roof by immunoflourescent mapping. Electron microscopy revealed a blister cleavage plane below the lamina densa. The histology of the lichenoid papules showed amyloid deposition in the papillary dermis. Because it was confined to just beneath the bulla base of the blister specimen, the amyloid deposition may have been derived from degenerated keratinocytes induced by damage to the epidermal-dermal junction due to blister formation in PDEB in this case. PDEB, in general, is often misdiagnosed as lichen amyloidosis; however, some PDEB cases could actually be associated with amyloid deposition.

Inherited epidermolysis bullosa

Inherited epidermolysis bullosa (EB) encompasses a number of disorders characterized by recurrent blister formation as the result of structural fragility within the skin and selected other tissues. All types and subtypes of EB are rare; the overall incidence and prevalence of the disease within the United States is approximately 19 per one million live births and 8 per one million population, respectively. Clinical manifestations range widely, from localized blistering of the hands and feet to generalized blistering of the skin and oral cavity, and injury to many internal organs. Each EB subtype is known to arise from mutations within the genes encoding for several different proteins, each of which is intimately involved in the maintenance of keratinocyte structural stability or adhesion of the keratinocyte to the underlying dermis. EB is best diagnosed and subclassified by the collective findings obtained via detailed personal and family history, in concert with the results of immunofluorescence antigenic mapping, transmission electron microscopy, and in some cases, by DNA analysis. Optimal patient management requires a multidisciplinary approach, and revolves around the protection of susceptible tissues against trauma, use of sophisticated wound care dressings, aggressive nutritional support, and early medical or surgical interventions to correct whenever possible the extracutaneous complications. Prognosis varies considerably and is based on both EB subtype and the overall health of the patient.