The eye in epidermolysis bullosa

A Spatiotemporal and Machine-Learning Platform Accelerates the Manufacturing of hPSC-derived Esophageal Mucosa

Human pluripotent stem cell-derived tissue engineering offers great promise in designer cell-based personalized therapeutics. To harness such potential, a broader approach requires a deeper understanding of tissue-level interactions. We previously developed a manufacturing system for the ectoderm-derived skin epithelium for cell replacement therapy. However, it remains challenging to manufacture the endoderm-derived esophageal epithelium, despite both possessing similar stratified structure. Here we employ single cell and spatial technologies to generate a spatiotemporal multi-omics cell atlas for human esophageal development. We illuminate the cellular diversity, dynamics and signal communications for the developing esophageal epithelium and stroma. Using the machine-learning based Manatee, we prioritize the combinations of candidate human developmental signals for in vitro derivation of esophageal basal cells. Functional validation of the Manatee predictions leads to a clinically-compatible system for manufacturing human esophageal mucosa. Our approach creates a versatile platform to accelerate human tissue manufacturing for future cell replacement therapies to treat human genetic defects and wounds.

The conjunctival extracellular matrix, related disorders and development of substrates for conjunctival restoration

The conjunctiva can be damaged by numerous diseases with scarring, loss of tissue and dysfunction. Depending on extent of damage, restoration of function may require a conjunctival graft. A wide variety of biological and synthetic substrates have been tested in the search for optimal conditions for ex vivo culture of conjunctival epithelial cells as a route toward tissue grafts. Each substrate has specific advantages but also disadvantages related to their unique physical and biological characteristics, and identification and development of an improved substrate remains a priority. To achieve the goal of mimicking and restoring a biological material, requires information from the material. Specifically, extracellular matrix (ECM) derived from conjunctival tissue. Knowledge of the composition and structure of native ECM and identifying contributions of individual components to its function would enable using or mimicking those components to develop improved biological substrates. ECM is comprised of two components: basement membrane secreted predominantly by epithelial cells containing laminins and type IV collagens, which directly support epithelial and goblet cell adhesion differentiation and growth and, interstitial matrix secreted by fibroblasts in lamina propria, which provides mechanical and structural support. This review presents current knowledge on anatomy, composition of conjunctival ECM and related conjunctival disorders. Requirements of potential substrates for conjunctival tissue engineering and transplantation are discussed. Biological and synthetic substrates and their components are described in an accompanying review.

Eye Involvement and Management in Inherited Epidermolysis Bullosa

Inherited epidermolysis bullosa (EB) is a group of genetic rare diseases associated with skin fragility, which leads to the formation of blisters, erosions, and scars on the skin and mucous membranes. Epidermolysis bullosa includes four main types and some several clinical subtypes including EB simplex, junctional EB, dystrophic EB, and Kindler's EB. Ocular involvement ranged from 51 to 68% in EB and can cause irreversible damages if not properly managed. Corneal erosions are the most common finding among series, including our cohort. We review here clinical and pathological features of ocular involvement in EB and the main keys for management, with a focus on recent innovative therapies.

Pseudopterygium: An Algorithm Approach Based on the Current Evidence

Pseudopterygium is a non-progressive conjunctival adhesion to the peripheral cornea secondary to a corneal-limbus damage. According to the literature, the main etiology is a previous eye trauma. Nevertheless, this could be biased by the existence of other underdiagnosed causes of pseudopterygium, some of which may have severe consequences for the integrity of the eye and patient’s life. This comprehensive literature review was performed based on a search on the PubMed and Google Scholar databases of relevant pseudopterygium published papers according to our current knowledge and seeks to gather the existing evidence about its diverse etiologies and clinical features, as well as to propose a diagnostic algorithm to simplify its correct approach.

Detection of Novel Biallelic Causative Variants in COL7A1 Gene by Whole-Exome Sequencing, Resulting in Congenital Recessive Dystrophic Epidermolysis Bullosa in Three Unrelated Families

Background: Dystrophic Epidermolysis bullosa (DEB) is a rare, severe subtype of epidermolysis bullosa (EB), characterized by blisters and miliary rashes of the skin. Dystrophic EB (DEB) includes variants inherited both in an autosomal-dominant or autosomal-recessive manner. Recessive dystrophic EB (RDEB) is divided into many subtypes and prevails as a result of biallelic genetic mutations in COL7A1 gene encoding type VII collagen, a major stabilizing molecule of the dermo-epidermal junction. The blister formation is mainly due to the variable structural and functional impairment of anchoring fibrils in VII collagen (COLVII), responsible for the adhesion of the epidermis to the dermis. Method: Three Pakistani families (A, B and C) affected with congenital dystrophic epidermolysis bullosa were recruited in the present study. The whole-exome sequencing (WES) approach was utilized for the detection of the pathogenic sequence variants in probands. The segregation of these variants in other participants was confirmed by Sanger sequencing. Results: This study identified a novel missense variant c.7034G>A, p. Gly2345Asp in exon 91, a novel Frameshift mutation c.385del (p. His129MetfsTer18) in a homozygous form in exon no 3, and a previously known nonsense variation (c.1573 C>T; p. Arg525Ter) in exon 12 of COL7A1 gene in families A, B, and C, respectively, as causative mutations responsible for dystrophic epidermolysis bullosa in these families. Conclusion: Our study validates the involvement of the COL7A1 gene in the etiology of dystrophic epidermolysis bullosa. It further expands the COL7A1 gene mutation database and provides an additional scientific basis for diagnosis, genetic counseling, and prognosis purposes for EB patients.

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.

Controversy and Consideration of Refractive Surgery in Patients with Heritable Disorders of Connective Tissue

Heritable Disorders of Connective Tissue (HDCTs) are syndromes that disrupt connective tissue integrity. They include Osteogenesis Imperfecta (OI), Ehlers Danlos Syndrome (EDS), Marfan Syndrome (MFS), Loeys-Dietz Syndrome (LDS), Epidermolysis Bullosa (EB), Stickler Syndrome (STL), Wagner Syndrome, and Pseudoxanthoma Elasticum (PXE). Because many patients with HDCTs have ocular symptoms, commonly myopia, they will often present to the clinic seeking refractive surgery. Currently, corrective measures are limited, as the FDA contraindicates laser-assisted in-situ keratomileusis (LASIK) in EDS and discourages the procedure in OI and MFS due to a theoretically increased risk of post-LASIK ectasia, poor wound healing, poor refractive predictability, underlying keratoconus, and globe rupture. While these disorders present with a wide range of ocular manifestations that are associated with an increased risk of post-LASIK complications (e.g., thinned corneas, ocular fragility, keratoconus, glaucoma, ectopia lentis, retinal detachment, angioid streaks, and ocular surface disease), their occurrence and severity are highly variable among patients. Therefore, an HDCT diagnosis should not warrant an immediate disqualification for refractive surgery. Patients with minimal ocular manifestations can consider LASIK. In contrast, those with preoperative signs of corneal thinning and ocular fragility may find the combination of collagen cross-linking (CXL) with either photorefractive keratotomy (PRK), small incision lenticule extraction (SMILE) or a phakic intraocular lens (pIOL) implant to be more suitable options. However, evidence of refractive surgery performed on patients with HDCTs is limited, and surgeons must fully inform patients of the unknown risks and complications before proceeding. This paper serves as a guideline for future studies to evaluate refractive surgery outcomes in patients with HDCTs.

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.

A systematic literature review of the disease burden in patients with recessive dystrophic epidermolysis bullosa

BACKGROUND/OBJECTIVE

Recessive dystrophic epidermolysis bullosa (RDEB) is a genetic collagen disorder characterized by skin fragility leading to blistering, wounds, and scarring. There are currently no approved curative therapies. The objective of this manuscript is to provide a comprehensive literature review of the disease burden caused by RDEB.

METHODS

A systematic literature review was conducted in MEDLINE and Embase in accordance with PRISMA guidelines. Observational and interventional studies on the economic, clinical, or humanistic burden of RDEB were included.

RESULTS

Sixty-five studies were included in the review. Patients had considerable wound burden, with 60% reporting wounds covering more than 30% of their body. Increases in pain and itch were seen with larger wound size. Chronic wounds were larger and more painful than recurrent wounds. Commonly reported symptoms and complications included lesions and blistering, anemia, nail dystrophy and loss, milia, infections, musculoskeletal contractures, strictures or stenoses, constipation, malnutrition/nutritional problems, pseudosyndactyly, ocular manifestations, and dental caries. Many patients underwent esophageal dilation (29-74%; median dilations, 2-6) and gastrostomy tube placement (8-58%). In the severely affected population, risk of squamous cell carcinoma (SCC) was 76% and mortality from SCC reached 84% by age 40. Patients with RDEB experienced worsened quality of life (QOL), decreased functioning and social activities, and increased pain and itch when compared to other EB subtypes, other skin diseases, and the general population. Families of patients reported experiencing high rates of burden including financial burden (50-54%) and negative impact on private life (79%). Direct medical costs were high, though reported in few studies; annual payer-borne total medical costs in Ireland were $84,534 and annual patient-borne medical costs in Korea were $7392. Estimated annual US costs for wound dressings ranged from $4000 to $245,000. Patients spent considerable time changing dressings: often daily (13-54% of patients) with up to three hours per change (15-40%).

CONCLUSION

Patients with RDEB and their families/caregivers experience significant economic, humanistic, and clinical burden. Further research is needed to better understand the costs of disease, how the burden of disease changes over the patient lifetime and to better characterize QOL impact, and how RDEB compares with other chronic, debilitating disorders.

Limbal stem cell diseases

The function of limbal stem/progenitor cells (LSCs) is critical to maintain corneal epithelial homeostasis. Many external insults and intrinsic defects can be deleterious to LSCs and their niche microenvironment, resulting in limbal stem cell dysfunction or deficiency (LSCD). Ocular comorbidities, frequent in eyes with LSCD, can exacerbate the dysfunction of residual LSCs, and limit the survival of transplanted LSCs. Clinical presentation and disease evolution vary among different etiologies of LSCD. New ocular imaging modalities and molecular markers are now available to standardize the diagnosis criteria and stage the severity of the disease. Medical therapies may be sufficient to reverse the disease if residual LSCs are present. A stepwise approach should be followed to optimize the ocular surface, eliminate the causative factors and treat comorbid conditions, before considering surgical interventions. Furthermore, surgical options are selected depending on the severity and laterality of the disease. The standardized diagnostic criteria to stage the disease is necessary to objectively evaluate and compare the efficacy of the emerging customized therapies.

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.

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.

Ophthalmologic Approach in Epidermolysis Bullosa: A Cross-Sectional Study With Phenotype-Genotype Correlations

PURPOSE

This study describes ophthalmologic and systemic clinical findings in different subtypes of epidermolysis bullosa (EB) establishing genotype-phenotype correlations.

METHODS

A cross-sectional study was conducted in 58 patients with EB together with the Dystrophic Epidermolysis Bullosa Research Association, Chile. Data were stratified by major subtypes such as "simplex epidermolysis bullosa" (EBS), "junctional epidermolysis bullosa" (JEB), "recessive and dominant dystrophic epidermolysis bullosa" and "dominant dystrophic epidermolysis bullosa" (DDEB), and "Kindler syndrome" (KS). The diagnosis was confirmed by skin immunofluorescence mapping and genetic testing. Best-corrected visual acuity, corneal erosions, corneal scarring, symblepharon, blepharitis, ectropion, limbal stem cell deficiency, and esophageal involvement were assessed. Clinical outcome was based on the presence of corneal involvement attributable to EB.

RESULTS

The most common ocular manifestations were corneal erosion/scarring and recurrent erosions. Frequencies of the EB subtypes were as follows: 17% EBS, 12% JEB, 16% DDEB, 53% recessive and DDEB, and 2% KS. Patients with EBS and DDEB did not reveal ocular involvement. Patients with recessive dystrophic epidermolysis bullosa (RDEB) were most affected by the disease showing corneal involvement in 16 cases, whereas 2 patients with JEB and the single KS case also showed corneal disease. Before their visit, 24 patients had undergone esophageal dilation, 23 of them with RDEB and 1 with KS.

CONCLUSIONS

Although ophthalmic complications are common in EB, the incidence varied with the EB subtype. We also establish the correlation between esophageal and corneal involvement in RDEB.

TFOS DEWS II pathophysiology report

The TFOS DEWS II Pathophysiology Subcommittee reviewed the mechanisms involved in the initiation and perpetuation of dry eye disease. Its central mechanism is evaporative water loss leading to hyperosmolar tissue damage. Research in human disease and in animal models has shown that this, either directly or by inducing inflammation, causes a loss of both epithelial and goblet cells. The consequent decrease in surface wettability leads to early tear film breakup and amplifies hyperosmolarity via a Vicious Circle. Pain in dry eye is caused by tear hyperosmolarity, loss of lubrication, inflammatory mediators and neurosensory factors, while visual symptoms arise from tear and ocular surface irregularity. Increased friction targets damage to the lids and ocular surface, resulting in characteristic punctate epithelial keratitis, superior limbic keratoconjunctivitis, filamentary keratitis, lid parallel conjunctival folds, and lid wiper epitheliopathy. Hybrid dry eye disease, with features of both aqueous deficiency and increased evaporation, is common and efforts should be made to determine the relative contribution of each form to the total picture. To this end, practical methods are needed to measure tear evaporation in the clinic, and similarly, methods are needed to measure osmolarity at the tissue level across the ocular surface, to better determine the severity of dry eye. Areas for future research include the role of genetic mechanisms in non-Sjögren syndrome dry eye, the targeting of the terminal duct in meibomian gland disease and the influence of gaze dynamics and the closed eye state on tear stability and ocular surface inflammation.

Raising Awareness Among Healthcare Providers about Epidermolysis Bullosa and Advancing Toward a Cure

Objective: Epidermolysis bullosa (EB) is an orphan disease that affects about half a million people worldwide, but may not be familiar to all clinicians. The authors' goal was to present a short description of this condition and current research in the form of a narrative review. Methods: The authors reviewed the literature on epidermolysis bullosa in order to describe the condition and current genetic research. Results: There are at least 31 subtypes of EB, including junctional EB, dystrophic EB, and Kindler syndrome. Genetic research is crucial in finding strategies to manage and possibly cure EB, which is often undiagnosed or misdiagnosed. EB may present in newborns and may persist over the course of a lifetime. Serious complications can occur with EB, including chronic blisters, wounds, ulcers, pruritus, clubbing of hands and feet, and amputations. Pain is frequently reported. About 80 percent of patients with recessive dystrophic EB will succumb to squamous cell carcinoma by age 55. Promising directions for future research include genome editing, gene therapy, and cell-based therapies. Conclusion: Our growing understanding of genetics and cell therapies may lead to promising therapeutic advances to treat this challenging condition.

Long-term outcome after superficial keratectomy in an infant with epidermolysis bullosa

A 5-month-old boy presented with a congenital whitish raised lesion in the central cornea of the left eye. The child had a tendency to develop bullous eruptions on the skin with trivial trauma. The patient's father had a similar history of skin lesions. Because the lesion was in the central visual axis, a superficial anterior keratectomy with an amniotic membrane grafting was performed. The lesion healed well, restoring the corneal transparency and resulting in good visual acuity. When the boy was 4 years of age, his cornea was clear, and best-corrected visual acuity in the left eye was 20/60. There was no recurrence of the lesion.

The Frequency of Signs of Meibomian Gland Dysfunction in Children with Epidermolysis Bullosa

PURPOSE

To determine the frequency of meibomian gland dysfunction (MGD) in children with epidermolysis bullosa (EB).

DESIGN

Hospital-based cross-sectional study.

PARTICIPANTS

One hundred five children with different forms of EB.

METHODS

Prospective ophthalmic examination of children with EB presenting over seventeen months including meibomian gland assessment using a recognized classification.

MAIN OUTCOME MEASURES

Frequency of MGD.

RESULTS

One hundred five children were recruited, 8.6% with junctional EB, 34.3% with simplex EB, 34.3% with autosomal recessive dystrophic EB, and 22.9% autosomal dominant dystrophic EB. Mean age was 7.42 years (range, 0.08-17.75 years). Ninety-two children (87.62%) demonstrated 1 or more features of MGD.

CONCLUSIONS

Most children with EB exhibit signs of MGD. To the best of our knowledge, this is the first prospective ocular surface evaluation in children with EB to include lid margin evaluation using a recognized classification system. Our findings help explain some of the ocular surface anomalies seen in children with EB.

Ocular manifestations of genetic skin disorders

Genetic skin diseases, or genodermatoses, often have extracutaneous manifestations. Ocular manifestations in particular can have significant clinical implications, like blindness. Other manifestations, such as the corneal opacities that occur in X-linked ichthyosis, are asymptomatic but characteristic of a particular genodermatosis. Ophthalmologic examination can aid in diagnosis when characteristic findings are seen. The genodermatoses with ocular manifestations will be reviewed, but neurocutaneous, syndromes, genetic pigmentary disorders, and genetic metabolic diseases are not included because they are covered elsewhere in this issue.

Long-term follow-up of patients with Herlitz-type junctional epidermolysis bullosa

BACKGROUND

Junctional epidermolysis bullosa, type Herlitz (JEB-H) is a rare, autosomal recessive disease caused by absence of the epidermal basement membrane adhesion protein laminin-332. It is characterized by extensive and devastating blistering of the skin and mucous membranes, leading to death in early childhood.

OBJECTIVES

To present the results of the long-term follow-up of a cohort of patients with JEB-H, and to provide guidelines for prognosis, treatment and care.

METHODS

All patients with JEB-H included in the Dutch Epidermolysis Bullosa (EB) Registry between 1988 and 2011 were followed longitudinally by our EB team. Diagnosis was established using immunofluorescence antigen mapping, electron microscopy and DNA analysis.

RESULTS

In total, we included 22 patients with JEB-H over a 23-year period. Their average age at death was 5.8 months (range 0.5-32.6 months). The causes of death were, in order of frequency: failure to thrive, respiratory failure, pneumonia, dehydration, anaemia, sepsis and euthanasia. The pattern of initial weight gain was a predictor of lifespan in these patients. Invasive treatments to extend life did not promote survival in our patients.

CONCLUSIONS

It is important to diagnose JEB-H as soon as possible after birth so that the management can be shifted from life-saving to comfort care. The palliative end-of-life care can take place in hospital, but is also safe in the home setting. Suffering in patients with JEB-H can become so unbearable that in some patients who do not respond to adequate analgesic and sedative treatment, newborn euthanasia, performed according to the Groningen protocol, is legally permitted in the Netherlands.

Ocular surface reconstruction with cultivated limbal epithelium in a patient with unilateral stem cell deficiency caused by Epidermolysis bullosa dystrophica hallopeau-Siemens

PURPOSE

To report a case of partial limbal stem cell deficiency (LSCD) caused by epidermolysis bullosa dystrophica mutilans Hallopeau-Siemens treated by transplantation of autologous ex vivo expanded limbal epithelium.

METHODS

Review of the clinical findings of an 11.5-year-old boy with unilateral LSCD and epidermolysis bullosa dystrophica who underwent ocular surface reconstruction in the right eye with autologous on intact human amniotic membrane cultivated limbal epithelial cells.

RESULTS

Twenty-eight months after reconstruction, the corneal surface is clear, smooth, and stable showing no signs of LSCD recurrence. Three subconjunctival bevacizumab (Avastin) injections reduced the recurrent growth of symblepharon and corneal vascularization. The visual acuity has increased from hand motion to 20/50.

CONCLUSION

Autologous transplantation of cultivated human limbal epithelial cells on intact human amniotic membrane can be a safe and effective method for corneal surface reconstruction in LSCD caused by recessive epidermolysis bullosa dystrophica.

[Dry eye syndrome and neurotrophic keratitis in childhood. Causes and therapy]

PURPOSE

The purpose of this review is to enhance the physician's awareness of dry eye syndrome and neurotrophic keratitis in children, to describe the most frequently associated conditions and to discuss the diagnostic and therapeutic options available.

METHODS

A literature review of the pathogenesis of dry eye syndrome and neurotrophic keratitis in children was carried out, clinical cases from our pediatric ophthalmology office are presented as well as therapeutic strategies.

RESULTS

Diseases of the cornea and ocular surface such as dry eye syndrome, neurotrophic keratitis and corneal ulcers are infrequent in children compared to adults. However, they do occur and should be diagnosed and treated as soon as possible in order to prevent long-term complications and amblyopia.

CONCLUSIONS

Inflammatory diseases of the ocular surface can be easily overlooked in children due to the often unknown spectrum of differential diagnoses and the frequently reduced cooperation during examination of young children. Correct and early diagnosis is essential for prevention of long-term complications, e.g. corneal ulceration and scarring.

Surgical management of infantile cataracts in dystrophic epidermolysis bullosa

Epidermolysis bullosa describes a group of mechanobullous skin diseases that result in the formation of blisters with little or no trauma. In dystrophic epidermolysis bullosa, the eyelid skin and ocular surface are commonly affected; however, infantile cataracts are a rare occurrence. A 7-month-old boy with dense bilateral cataracts and nystagmus underwent cataract extraction, lens implantation, and limited vitrectomy with the use of specialized techniques to reduce iatrogenic skin and ocular surface complications. No iatrogenic skin or ocular surface complications were observed postoperatively. At 24 months of age, the child demonstrated improved visual function.

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

Based upon case reports and small case series, it has been known for many years that some types and subtypes of inherited epidermolysis bullosa (EB) may be at risk for developing one or more extracutaneous complications. Many of these are associated with considerable morbidity; some may result in death. Only over the past few years have there been data generated from large, well characterized cohorts. However, these data, to date, have been published almost exclusively in the nondermatologic literature. Our objective is to provide dermatologists with a comprehensive review of each major extracutaneous complication with a summary of the pertinent literature and recommendations for evaluation and optimal management. Part I highlights epithelial associated tissues, and part II addresses other organs. Based on these reviews, the readership should gain a greater understanding of the types of complications that may occur, when they are most likely to develop, and the range of medical and surgical interventions that are currently available. It should also be possible for the reader to develop surveillance strategies based on an understanding of the published evidence-based data. The breadth and range of severity of complications that arise in some EB types and subtypes within the external eye, ear, nose, upper airway, and gastrointestinal and genitourinary tracts suggest that optimal management must be multidisciplinary. Given the unique knowledge that dermatologists have of this disease, we believe that the care of the EB patient should be under the direction of his or her dermatologist, who can best assist in timely referrals to those specialists who are most experienced in the care of specific extracutaneous problems.

Epidermolysis bullosa. Part 1: causes, presentation and complications

This article is the first in a series of three focusing on the causes, clinical presentation, complications and care of adult patients affected by epidermolysis bullosa (EB), a group of rare genetic skin fragility disorders. Although the condition is rare, in some cases it presents extreme challenges both to those affected and those involved in the care of the EB patient; therefore, these articles may have relevance for other long-term disorders. While there is a wealth of information regarding the 'science' of EB there is dearth of information regarding the care of the adult EB patient, and this series of articles will endeavour to fill that gap. This article focuses mainly on those patients affected with the most severe form of EB found in the adult group, recessive dystrophic epidermolysis bullosa; with the part two looking at the care of the adult with EB from the nursing perspective, including wound management, and the experiences of a specialist EB psychotherapist being presented in the final article of the series. Readers will thus have an opportunity to gain an overall view of this difficult condition.

External ocular manifestations in autosomal dominant dystrophic epidermolysis bullosa; a case report

PURPOSE

To present a case of autosomal dominant dystrophic epidermolysis bullosa with symblepharon formation due to eye rubbing.

CASE REPORT

A 10-year-old girl suffering from blistering and ulcerative lesions of the trunk and palms and dystrophic nails since childhood was referred to our clinic with a symblepharon connecting the medial portion of the right upper lid to the superonasal quadrant of the cornea. The central cornea in both eyes exhibited mild subepithelial opacification. She had history of eye rubbing due to foreign body sensation in the right eye, resulting in red eye and blister-like conjunctival lesions since three years ago. She had previously undergone surgical symblepharon removal leading to more severe recurrence of the condition.

CONCLUSION

Dominant dystrophic epidermolysis bullosa may be accompanied by external ocular manifestations. Protection of the eye from minor trauma such as rubbing may help prevent ocular complications.

Amniotic membrane transplantation for treatment of symblepharon in a patient with recessive dystrophic epidermolysis bullosa

PURPOSE

To report the surgical treatment of a case with epidermolysis bullosa.

METHODS

A 12-year-old girl with dystrophic epidermolysis bullosa presented to our clinic with a symblepharon connecting the lateral half of the left upper lid to the upper temporal quadrant of the cornea. The central cornea exhibited diffuse opacity and vascularization.

RESULTS

During surgery, the symblepharon was lysed, and lamellar keratectomy was performed. The operated portion of cornea and palpebral conjunctiva was covered with amniotic membrane to promote healing. Fourteen months later, the operated eyelid margin was normal and the eye was fully mobile. The temporal portion of the corneal stroma was still thinner than normal and showed mild superficial vascularization and opacification.

CONCLUSION

We believe that amniotic membrane transplantation is a valuable way to treat symblepharon in cases of epidermolysis bullosa.

Corneal ulcer in a young child with autosomal recessive epidermolysis bullosa

Ocular manifestations of epidermolysis bullosa typically occur in patients with severe skin findings and are more likely with increasing age. An 18-month-old boy with relatively mild dermatologic epidermolysis bullosa developed corneal ulceration and scarring.

Dystrophic epidermolysis bullosa: Oral findings and problems

Dystrophic epidermolysis bullosa (DEB) is one of the three major types of epidermolysis bullosa (EB), an inherited cutaneous disease with blister formation following minor trauma. A subtype of DEB is recessive dystrophic epidermolysis bullosa, Hallopeau-Siemens type (RDEB-HS), where marked scarring leads to deformities of extremities. In RDEB-HS the mucous membranes may also be involved and form adhesions with ankyloglossia and microstomia. Oral hygiene is difficult. A 7-year-old boy with RDEB-HS was brought to the Johannes Gutenberg University dental clinic with dental pain. He had multiple carious lesions, poor oral hygiene and gingivitis. Because he was noncompliant and had microstomia, he required dental therapy under general anesthesia. The recall visits over the past two years had demonstrated that the dental health of this patient with RDEB-HS could be maintained by means of improved oral home care, using antibacterial agents.

Junctional epidermolysis bullosa in two domestic shorthair kittens

This article describes two cases of junctional epidermolysis bullosa in nonrelated kittens. Both cats exhibited pinnal erosions, oral ulcerations and severe onychomadesis. Histopathology, electron microscopy and/or indirect immunoperoxidase revealed subepidermal clefting, with the lamina densa remaining attached to the floor of the vesicles. Indirect immunofluorescence revealed reduced staining for laminin-5 gamma2 subunit in case 1 and beta3 subunit in case 2.

Collagens and collagen-related matrix components in the human and mouse eye

The three-dimensional structure of the eye plays an important role in providing a correct optical environment for vision. Much of this function is dependent on the unique structural features of ocular connective tissue, especially of the collagen types and their supramolecular structures. For example, the organization of collagen fibrils is largely responsible for transparency and refraction of cornea, lens and vitreous body, and collagens present in the sclera are largely responsible for the structural strength of the eye. Phylogenetically, most of the collagens are highly conserved between different species, which suggests that collagens also share similar functions in mice and men. Despite considerable differences between the mouse and the human eye, particularly in the proportion of the different tissue components, the difficulty of performing systematic histologic and molecular studies on the human eye has made mouse an appealing alternative to studies addressing the role of individual genes and their mutations in ocular diseases. From a genetic standpoint, the mouse has major advantages over other experimental animals as its genome is better known than that of other species and it can be manipulated by the modern techniques of genetic engineering. Furthermore, it is easy, quick and relatively cheap to produce large quantities of mice for systematic studies. Thus, transgenic techniques have made it possible to study consequences of specific mutations in genes coding for structural components of ocular connective tissues in mice. As these changes in mice have been shown to resemble those in human diseases, mouse models are likely to provide efficient tools for pathogenetic studies on human disorders affecting the extracellular matrix. This review is aimed to clarify the role of collagenous components in the mouse and human eye with a closer look at the new findings of the collagens in the cartilage and the eye, the so-called "cartilage collagens".

Eye involvement in inherited epidermolysis bullosa: experience of the National Epidermolysis Bullosa Registry

PURPOSE

To determine the frequency of ocular manifestations in inherited epidermolysis bullosa (EB) within the continental United States and to define the estimated cumulative risks of developing nonscarring (blisters or erosions) and scarring corneal manifestations within each major EB subtype over time.

DESIGN

Observational (cross-sectional and longitudinal).

METHODS

Up to 16 years of longitudinal follow-up was conducted on 3,280 consecutively enrolled patients in the National EB Registry, an epidemiologic study funded by the National Institutes of Health. Data were stratified by major EB type and subtype. Frequencies of occurrence were determined for eight variables (corneal erosions or blistering; corneal scarring; symblepharons; blepharitis; ectropions; lacrimal duct obstruction; impaired vision; blindness) by contingency tables, and cumulative risks were generated by life table analysis technique.

RESULTS

The most common ocular manifestations were corneal erosions and blisters. Frequencies mirrored relative severity of skin disease, with 74.10% of all patients with recessive dystrophic EB, Hallopeau-Siemens (RDEB-HS) and 47.50% of all patients with junctional EB, Herlitz (JEB-H) experiencing at least one episode. Lower frequencies were noted for corneal scarring. Symblepharons and ectropions were most commonly seen in inversa RDEB and JEB-H, respectively. Blindness was reported in 6.47% of RDEB-HS patients. The cumulative risks of nonscarring and scarring corneal lesions in JEB-H at age 5 are 83.18% and 27.08% and at age 25 are 83.18% and 72.22%. With time, the cumulative risk of each in RDEB-HS approached that reported in JEB-H patients.

CONCLUSION

Ocular disease activity, particularly corneal, is common in some EB subtypes. Careful ophthalmologic examination should become an integral part of the management of all patients with inherited EB.

Epidermolysis bullosa: new and emerging trends

Epidermolysis bullosa is a family of inherited blistering skin disorders characterized by blister formation in response to mechanical trauma. Major types of epidermolysis bullosa include epidermolysis bullosa simplex, hemidesmosomal epidermolysis bullosa, junctional epidermolysis bullosa, and dystrophic epidermolysis bullosa. Current treatment for epidermolysis bullosa consists of supportive care for skin and other organ systems and entails a combination of wound management, infection support for chronic wounds, surgical management as needed, nutritional support, and preventative screening for squamous cell carcinoma in recessive dystrophic epidermolysis bullosa. The regimen must be tailored specifically to the severity and extent of skin and systemic involvement in each case. Recent studies have identified specific protein and genetic abnormalities for most epidermolysis bullosa subtypes. These new advancements in the understanding of molecular pathophysiology have provided much of the basis for current efforts to develop effective gene and protein therapy for epidermolysis bullosa.

Laminins and human disease

The laminin protein family has diverse tissue expression patterns and is involved in the pathology of a number of organs, including skin, muscle, and nerve. In the skin, laminins 5 and 6 contribute to dermal-epidermal cohesion, and mutations in the constituent chains result in the blistering phenotype observed in patients with junctional epidermolysis bullosa (JEB). Allelic heterogeneity is observed in patients with JEB: mutations that results in premature stop codons produce a more severe phenotype than do missense mutations. Gene therapy approaches are currently being studied in the treatment of this disease. A blistering phenotype is also observed in patients with acquired cicatricial pemphigoid (CP). Autoantibodies targeted against laminins 5 and 6 destabilize epithelial adhesion and are pathogenic. In muscle cells, laminin alpha 2 is a component of the bridge that links the actin cytoskeleton to the extracellular matrix. In patients with laminin alpha 2 mutations, the bridge is disrupted and mature muscle cells apoptose. Congenital muscular dystrophy (CMD) results. The role of laminin in diseases of the nervous system is less well defined, but the extracellular protein has been shown to serve an important role in peripheral nerve regeneration. The adhesive molecule influences neurite outgrowth, neural differentiation, and synapse formation. The broad spatial distribution of laminin gene products suggests that laminin may be involved in a number of diseases for which pathogenic mechanisms are still being unraveled.