Novel pathogenic variants in an Indian cohort with epidermolysis bullosa: Expanding the genotypic spectrum

BackgroundEpidermolysis bullosa (EB) is a genodermatosis characterized by skin fragility and blisters with variable severity. Patients with Dystrophic EB (DEB) or Junctional EB (JEB) mainly present to clinic due to greater functional impairment. Pathogenic sequence variations in COL7A1 are implicated in DEB.ObjectiveWe have tried to decipher the molecular spectrum and genotype phenotype correlation of 21 Indian patients with EB.MethodsNext generation sequencing (NGS) was performed to determine the pathogenic variants. Sanger sequencing was also done for validation of the variants in eleven individuals.ResultsPathogenic variants were detected in 20 individuals (diagnostic yield of 95%). Majority of them (90%) had sequence variation in COL7A1 while two had pathogenic variants in ITGB4 and KRT14 respectively. Out of the 18 patients confirmed to have DEB, 3 had Dominant DEB (DDEB) whereas 15 patients had Recessive DEB (RDEB). Amongst 23 sequence variations identified, 12 were found to be novel (3 were missense, 5 were premature termination codon variants while 4 were splice-site changes).ConclusionGenotype phenotype correlation was noted with milder manifestations in those with dominant inheritance types. Exact molecular diagnosis can be ascertained by NGS in majority of cases.     

先天性皮肤缺损三例报告并文献复习

目的 探讨先天性皮肤缺损的病因、分类、治疗及预后,提高该病的诊治水平.方法 回顾性分析我院治疗的3例先天性皮肤缺损患儿发病特点、治疗过程、方法,并复习国内外文献中报道的皮肤缺损305例,总结先天性皮肤缺损的临床特点及诊治经验.结果 3例患儿缺损皮肤均由羊皮纸样瘢痕组织愈合,无组织挛缩,无活动障碍.305例患儿中死亡8例;保守治疗234例;手术治疗63例,其中因瘢痕挛缩影响肢体功能者5例.该病致死率、致残率低,预后良好.结论 先天性皮肤缺损是一种病因尚不明确的疾病,创面表浅者多可经保守治疗后痊愈,骨外露、重要脏器外露、深度缺损宜适时采用手术治疗,该疾病若能给予正确处理,预后良好,对患儿日常生活影响小.     

Clinical and immunological studies for 105 Japanese seropositive patients of epidermolysis bullosa acquisita examined at Kurume University

Objectives: Using our serological diagnostic criteria, we selected 105 Japanese patients with epidermolysis bullosa acquisita (EBA), an autoimmune bullous disease (AIBD) reacting with type VII collagen, from our cohort of 5063 AIBD patients.

Methods: We examined the patients clinically and immunologically.

Results: We found diversity of clinical manifestations in both cutaneous and oral mucosal lesions and a high rate of inflammatory-type EBA patients in Japan. Common treatments were systemic steroids, followed by immunosuppressives, DDS, tetracycline/minocycline and colchicine. Immunological studies revealed that indirect immunofluorescence of 1M-NaCl-split skin, immunoblotting of dermal extract, and type VII collagen ELISA were sensitive methods, with possible multiplicity of circulating autoantibodies against other basement membrane autoantigens.

Conclusion: The present study analyzed the largest cohort of EBA patients, confirming the scarcity of EBA (only 105 of the 5063 AIBD patients), and showed that the three serological tests are useful for the diagnosis of EBA.     

Clinical evaluation of patients with epidermolysis bullosa: Review of the literature and case reports

Epidermolysis bullosa (EB) is a relatively rare inherited disorder, which includes blister and vesicle formation on the skin and mucous membranes as a result of trauma or heat. There are different forms of this disorder. Mild manifestations are relatively uncomfortable, usually involving the knees, elbows, and fingers. Severe forms of this disease compromise normal functioning of multiple organs, which may result in premature death. The lack of a specific treatment to cure EB makes genetic counseling and prenatal diagnosis of primary importance to control this disorder. Three case histories of persons with dystrophic recessive epidermolysis bullosa are reported, focusing on appropriate dental care for patients with EB.     

Identification of the LAMB3 hotspot mutation R635X in a Hungarian case of Herlitz junctional epidermolysis bullosa

Abstract The Herlitz type of junctional epidermolysis bullosa (H-JEB) is a serve blistering disease affecting the skin and mucous membranes, which is usually lethal within the first year of life. The laminin 5 genes have been implicated as candidate genes for most patients with H-JEB. Recently two hotspot mutations were delineated in the LAMB3 gene, known as R42X and R635X, and have been noted in over 50% of mutant LAMB3 alleles. Here, we present a case of H-JEB of Hungarian origin with a neonatal lethal outcome. Monoclonal antibody staining showed a lack of expression of the laminin 5β3 chain, as a possible result of a mutation in one of the laminin 5 genes. Screening of the family identified the previously described mutation R635X in exon 14 of LAMB3 in each of the parents and one healthy sibling in the heterozygous form, while proband was homozygous for R635X, and the other sibling proved to be genotypically normal. These results underscore the widespread prevalence of R635X in H-JEB cases form around the world.     

中毒性表皮松解症的护理

目的 总结中毒性表皮松解症（TEN）患者的护理经验，提高护理质量，有效地促进患者康复。方法 对我院皮肤科2000～2004年收治的15例TEN患者，从皮肤、眼部并发症以及各重要系统并发症的护理及营养支持，感染控制，心理支持等方面进行总结。结果 15例患者中13例痊愈出院，2例分别继发肺部感染和感染综合征死亡。结论 细致到位的护理在TEN患者的治疗过程中起到了重要作用，能有效的促进患者康复。     

Transplantation of autologous single hair units heals chronic wounds in autosomal recessive dystrophic epidermolysis bullosa: A proof-of-concept study

Autosomal recessive dystrophic epidermolysis bullosa (RDEB) is characterized by recurrent mucocutaneous blistering with non-healing ulcers which are often complicated by squamous cell carcinoma (SCC). Despite having as high as 80% death rate from SCC, RDEB still does not have an effective treatment. We report on the efficacy of single follicular unit extract (FUE) grafting to heal chronic ulcers of intermediate RDEB in a 54-year-old woman with extensive chronic wounds covering around 30% of the body surface area. On Day 17 post first graft session, the area of treated ulcers on her right upper back was reduced by 80%. Immunofluorescence study revealed positive type VII collagen expression along the epidermal and follicular basement membrane zone in the donor and recipient sites. A few grafted follicles continued to grow hair on the recipient sites. A total of 360 FUEs were grafted in nine sessions over five years, resulting in healing of most treated ulcers and reduced significantly her time for daily wound dressing. Importantly, FUE grafting using patient's own scalp follicles does not require any laboratory manipulation. It is safe and easy to perform. Autologous follicular grafting appears efficacious for healing of recalcitrant wounds and provides an innovative solution for RDEB patients with such wounds.     

Inherited blistering skin diseases: underlying molecular mechanisms and emerging therapies

Abstract

A key function of human skin is the formation of a structural barrier against the external environment. In part, this is achieved through the formation of a cornified cell envelope derived from a stratified squamous epithelium attached to an epithelial basement membrane. Resilient in health, the structural integrity of skin can become impaired or break down in a collection of inherited skin diseases, referred to as the blistering genodermatoses. These disorders arise from inherited gene mutations in a variety of structural and signalling proteins and manifest clinically as blisters or erosions following minor skin trauma. In some patients, blistering can be severe resulting in significant morbidity. Furthermore, a number of these conditions are associated with debilitating extra-cutaneous manifestations including gastro-intestinal, cardiac, and ocular complications. In recent years, an improved understanding of the molecular basis of the blistering genodermatoses has led to better disease classification and genetic counselling. For patients, this has also advanced translational research with the advent of new clinical trials of gene, protein, cell, drug, and small molecule therapies. Although curing inherited blistering skin diseases still remains elusive, significant improvements in patients’ quality of life are already being achieved.     

Ultrastructural Features of Epidermolysis Bullosa

Epidermolysis bullosa (EB), a heterogeneous group of hereditary diseases, varies in mode of inheritance, extent, severity, and presence or absence of scarring and dystrophy. Fourteen cases (13 in infants and 1 in a young adult) were studied. Subtyping by ultrastructural findings in normal and blistered skin biopsies was as follows: EB simplex (2), EB letalis (3), EBD dominant (2), and EBD recessive (7). One case diagnosed as recessive dystrophic by electron microscopy (EM) followed a benign course with little scaring and was re-classified clinically and after reviewing the EM as dominant dystrophic. Defining the level of bulla formation by EM allowed accurate diagnosis of subtypes. In 6 patients with EBD recessive, normal and bullous skin showed collagenolysis and no anchoring fibrils. In patients with EBD dominant, rudimentary fibrils were noted in normal skin. Whether absence of anchoring fibrils is primary or secondary in these two types and the role of collagenolysis remain unresolved.