Updated systematic review of randomized controlled trials of treatments for inherited forms of epidermolysis bullosa

Quality of systematic reviews on the treatment of vesiculobullous skin diseases. A meta-epidemiological study

BACKGROUND

Systematic reviews of Randomized Controlled Trials (RCTs) are considered high-level evidence to support a decision on therapeutic interventions, and their methodological quality is essential to provide reliable and applicable results.

OBJECTIVE

This meta-epidemiological study aimed to map and critically appraise systematic reviews assessing treatments for vesiculobullous skin diseases.

METHODS

We conducted a comprehensive search strategy on MEDLINE (via Pubmed) in December 2022 without restrictions to find systematic reviews evaluating pharmacological interventions for vesiculobullous skin diseases. The methodological quality was assessed using the AMSTAR-2 tool, and additional information was extracted. We identified nine systematic reviews published between 2002 and 2021, seven assessing pemphigus.

RESULTS

According to the AMSTAR-2 tool, 55.6% were classified as critically low quality, 22.2% as moderate quality, 11.1% as low and 11.1% as high quality. No review assessed the certainty of the evidence (GRADE); 86% of pemphigus reviews had at least two overlapping RCTs. There were some limitations regarding methodological flaws and the AMSTAR-2 tool use CONCLUSIONS: These findings reveal a frail methodological quality of systematic reviews about vesiculobullous diseases treatment that may impact the results. Therefore, methodological rigor is mandatory for future systematic reviews to avoid duplication of effort and increase the certainty of the evidence supporting decision-making.

Independent COL17A1 Variants in Cats with Junctional Epidermolysis Bullosa

Epidermolysis bullosa (EB), characterized by defective adhesion of the epidermis to the dermis, is a heterogeneous disease with many subtypes in human patients and domestic animals. We investigated two unrelated cats with recurring erosions and ulcers on ear pinnae, oral mucosa, and paw pads that were suggestive of EB. Histopathology confirmed the diagnosis of EB in both cats. Case 1 was severe and had to be euthanized at 5 months of age. Case 2 had a milder course and was alive at 11 years of age at the time of writing. Whole genome sequencing of both affected cats revealed independent homozygous variants in COL17A1 encoding the collagen type XVII alpha 1 chain. Loss of function variants in COL17A1 lead to junctional epidermolysis bullosa (JEB) in human patients. The identified splice site variant in case 1, c.3019+1del, was predicted to lead to a complete deficiency in collagen type XVII. Case 2 had a splice region variant, c.769+5G>A. Assessment of the functional impact of this variant on the transcript level demonstrated partial aberrant splicing with residual expression of wildtype transcript. Thus, the molecular analyses provided a plausible explanation of the difference in clinical severity between the two cases and allowed the refinement of the diagnosis in the affected cats to JEB. This study highlights the complexity of EB in animals and contributes to a better understanding of the genotype-phenotype correlation in COL17A1-related JEB.

Heterogeneity of reported outcomes in epidermolysis bullosa clinical research: a scoping review as a first step towards outcome harmonization

BACKGROUND

Epidermolysis bullosa (EB) is a rare, genetically and clinically heterogeneous group of skin fragility disorders. No cure is currently available, but many novel and repurposed treatments are upcoming. For adequate evaluation and comparison of clinical studies in EB, well-defined and consistent consensus-endorsed outcomes and outcome measurement instruments are necessary.

OBJECTIVES

To identify previously reported outcomes in EB clinical research, group these outcomes by outcome domains and areas and summarize respective outcome measurement instruments.

METHODS

A systematic literature search was performed in the databases MEDLINE, Embase, Scopus, Cochrane CENTRAL, CINAHL, PsycINFO and trial registries covering the period between January 1991 and September 2021. Studies were included if they evaluated a treatment in a minimum of three patients with EB. Two reviewers independently performed the study selection and data extraction. All identified outcomes and their respective instruments were mapped onto overarching outcome domains. The outcome domains were stratified according to subgroups of EB type, age group, intervention, decade and phase of clinical trial.

RESULTS

The included studies (n = 207) covered a range of study designs and geographical settings. A total of 1280 outcomes were extracted verbatim and inductively mapped onto 80 outcome domains and 14 outcome areas. We found a steady increase in the number of published clinical trials and outcomes reported over the past 30 years. The included studies mainly focused on recessive dystrophic EB (43%). Wound healing was reported most frequently across all studies and referred to as a primary outcome in 31% of trials. Great heterogeneity of reported outcomes was observed within all stratified subgroups. Moreover, a diverse range of outcome measurement instruments (n = 200) was identified.

CONCLUSIONS

We show substantial heterogeneity in reported outcomes and outcome measurement instruments in EB clinical research over the past 30 years. This review is the first step towards harmonization of outcomes in EB, which is necessary to expedite the clinical translation of novel treatments for patients with EB.

Epidermolysis bullosa simplex in sibling Eurasier dogs is caused by a PLEC non-sense variant

BACKGROUND

Plectin, a large linker protein found in many tissues, acts to connect components of the cytoskeleton to each other. In the epidermis, plectin binds keratin intermediate filaments to hemidesmosomes. A deficiency of plectin in the skin leads to blister formation in the basal layer and the disease epidermolysis bullosa simplex (EBS).

HYPOTHESIS/OBJECTIVES

To describe a novel blistering disease that arose spontaneously in a litter of puppies.

ANIMALS

Two female and one male 20-day-old Eurasier puppies, from a litter of six, were presented for evaluation of failure to thrive and then euthanized due to poor prognosis. The puppies had ulcers on the lips, tongue, nasal planum, paw pads and abdomen.

RESULTS

Immunolabelling on frozen skin for basement membrane proteins revealed patchy and weak to absent staining for plectin as compared with strong linear staining in normal dogs. Ultrastructurally, hemidesmosomes were irregularly shaped and had loss of distinction between inner and outer plaques. Pedigree analysis supported an autosomal recessive mode of inheritance. A premature stop codon was discovered in exon 27 of PLEC that resulted in the production of a severely truncated protein.

CONCLUSION

The study describes the first documented spontaneous EBS associated with a PLEC variant in domestic animals.

Epidermolysis bullosa and the partnership with autoimmunity: what should we assimilate?

Bullous skin diseases are characterized by genetic abnormalities related to structural epidermal proteins or organ-specific autoantibodies against the same proteins and are revealed by blister formation on skin or mucous membranes, with differences in blister depth, morphology, and topography. Both inherited and autoimmune forms of these disorders can be framed in the context of epidermolysis bullosa. Their clinical spectrum varies from early lethal to mild variants with normal life expectancy, and several distinct phenotypes differ for age of onset, extent, location and depth of skin and mucous lesions, or scarring severity. Recently, different inflammatory processes blended with autoimmune phenomena have been demonstrated in both inherited and acquired epidermolysis bullosa, revealing that this overlapping might cause substantial implications in terms of disease course and outcome. Although several associations between epidermolysis bullosa in its different variants and autoimmune diseases have been reported, it is not yet completely clear how it happens and why this association occurs in only some patients. Autoantibodies are the primary cause of the disease in acquired epidermolysis bullosa, whereas they can be produced as a secondary event due to genetically determined skin damage in inherited epidermolysis bullosa, contributing significantly to the worsening of the disease. The awareness of this overlap may help in identifying new therapeutic approaches with immunosuppressive drugs that could have a significant impact in terms of prognosis.

Successful hypothermia treatment of hypoxic-ischemic encephalopathy in a neonate with epidermolysis bullosa

Despite advances in the neonatal care, hypoxic ischemic encephalopathy in late preterm and term infants remains an important cause of morbidity and mortality. There is lack of data on the application of therapeutic hypothermia in the existence of severe skin lesions. Epidermolysis bullosa is a rare group of inherited conditions which causes blisters in skin and mucosal membranes. In this report, the authors describe a successful whole-body hypothermia treatment of severe hypoxic ischemic encephalopathy in a term newborn with dystrophic epidermolysis bullosa. They observed that therapeutic hypothermia may also be given in newborns with dystrophic epidermolysis bullosa without any complications.

Multicentre consensus recommendations for skin care in inherited epidermolysis bullosa

Background

Inherited epidermolysis bullosa (EB) comprises a highly heterogeneous group of rare diseases characterized by fragility and blistering of skin and mucous membranes. Clinical features combined with immunofluorescence antigen mapping and/or electron microscopy examination of a skin biopsy allow to define the EB type and subtype. Molecular diagnosis is nowadays feasible in all EB subtypes and required for prenatal diagnosis. The extent of skin and mucosal lesions varies greatly depending on EB subtype and patient age. In the more severe EB subtypes lifelong generalized blistering, chronic ulcerations and scarring sequelae lead to multiorgan involvement, major morbidity and life-threatening complications. In the absence of a cure, patient management remains based on preventive measures, together with symptomatic treatment of cutaneous and extracutaneous manifestations and complications. The rarity and complexity of EB challenge its appropriate care. Thus, the aim of the present study has been to generate multicentre, multidisciplinary recommendations on global skin care addressed to physicians, nurses and other health professionals dealing with EB, both in centres of expertise and primary care setting.

Methods

Almost no controlled trials for EB treatment have been performed to date. For this reason, recommendations were prepared by a multidisciplinary team of experts from different European EB centres based on available literature and expert opinion. They have been subsequently revised by a panel of external experts, using an online-modified Delphi method to generate consensus.

Results

Recommendations are reported according to the age of the patients. The major topics treated comprise the multidisciplinary approach to EB patients, global skin care including wound care, management of itching and pain, and early diagnosis of squamous cell carcinoma. Aspects of therapeutic patient education, care of disease burden and continuity of care are also developed.

Conclusion

The recommendations are expected to be useful for daily global care of EB patients, in particular in the community setting. An optimal management of patients is also a prerequisite to allow them to benefit from the specific molecular and cell-based treatments currently under development.

Inherited epidermolysis bullosa: clinical and therapeutic aspects

Inherited epidermolysis bullosa (EB) is a heterogeneous group of genetic disorders that present with skin and, in some cases, mucosal fragility, predisposing patients to the development of blisters and/or erosions after minimal trauma or friction. Children with a recurrent history of these kinds of lesions or neonates that present them in the absence of another reasonable explanation should be investigated. Diagnosis must be based on clinical and histopathological findings. To date, management of inherited EB basically consists in avoiding traumas that trigger lesions, as well as preventing infection and facilitating healing of the wounds with the systematic use of bandages.

Prioritization of therapy uncertainties in Dystrophic Epidermolysis Bullosa: where should research direct to? an example of priority setting partnership in very rare disorders

Background

Dystrophic Epidermolysis Bullosa (DEB) is a rare genodermatosis (7 cases per million) that causes blisters and erosions with minor trauma in skin and mucosa, and other systemic complications. A recently updated systematic review showed that the research evidence about DEB therapies is poor. As new trials in DEB are difficult and expensive, it is important to prioritizise research that patients and clinicians consider more relevant.

Objectives

To describe and prioritize the most important uncertainties about DEB treatment shared by patients, carers and health care professionals (HCPs) in order to promote research in those areas.

Methods

A DEB Priority Setting Partnership (PSP) was established, including patients, carers and HCPs. DBE uncertainties were gathered from patients and clinicians, and prioritized in a transparent process, using the methodology advocated by the James Lind Alliance.

Results

In the consultation stage, 323 uncertainties were submitted by 58 participants. Once the duplicated and non-treatment uncertainties were removed, the remainder were reduced to a list of 24 most voted questions. These 24 uncertainties were prioritized in a final workshop where a balanced number of patients, carers and HCPs selected the top 10 therapy uncertainties. The final list includes interventions in wound care, itch and pain management, treatment and prevention of syndactyly, cancer prevention and future promising therapies.

Conclusions

The final list of the top 10 treatment uncertainties on the management of DEB provides guidance for researchers and funding bodies, to ensure that future research answers questions that are important to both clinicians and patients. The method proposed by the James Lind Alliance is feasible for very rare disorders.