Epidermolysis bullosa: new and emerging trends

Polymerizing laminins in development, health, and disease

Polymerizing laminins are multi-domain basement membrane (BM) glycoproteins that self-assemble into cell-anchored planar lattices to establish the initial BM scaffold. Nidogens, collagen-IV and proteoglycans then bind to the scaffold at different domain loci to create a mature BM. The LN domains of adjacent laminins bind to each other to form a polymer node, while the LG domains attach to cytoskeletal-anchoring integrins and dystroglycan, as well as to sulfatides and heparan sulfates. The polymer node, the repeating unit of the polymer scaffold, is organized into a near-symmetrical triskelion. The structure, recently solved by cryo-electron microscopy in combination with AlphaFold2 modeling and biochemical studies, reveals how the LN surface residues interact with each other and how mutations cause failures of self-assembly in an emerging group of diseases, the LN-lamininopathies, that include LAMA2-related dystrophy and Pierson syndrome.

Skin Microbial Composition and Genetic Mutation Analysis in Precision Medicine for Epidermolysis Bullosa

Epidermolysis bullosa (EB) is an inherited skin disease representing a spectrum of rare genetic disorders. These conditions share the common trait that causes fragile skin, resulting in the development of blisters and erosions. The inheritance follows an autosomal pattern, and the array of clinical presentations leads to significant physical suffering, considerable morbidity, and mortality. Despite EB having no cure, effectively managing EB remains an exceptional challenge due to its rarity and complexity, occasionally casting a profound impact on the lives of affected individuals. Considering that EB management requires a multidisciplinary approach, this sometimes worsens the condition of patients with EB due to inappropriate handling. Thus, more appropriate and precise treatment management of EB is essentially needed. Advanced technology in medicine and health comes into the bioinformatics era. Including treatment for skin diseases, omics-based approaches aim to evaluate and handle better disease management and treatment. In this work, we review several approaches regarding the implementation of omics-based technology, including genetics, pathogenic mutation, skin microbiomics, and metagenomics analysis for EB. In addition, we highlight recent updates on the potential of metagenomics analysis in precision medicine for EB.

Occam's Razor Versus Hickam's Dictum: A Case Report of Junctional Epidermolysis Bullosa and Lower Urinary Tract Infection

Epidermolysis bullosa (EB) is a rare heterogeneous group of diseases which typically presents with extensive blistering and mucocutaneous erosions. EB is mechanobullous in nature and thus commonly involves sites of trauma and friction. It is a painful and disfiguring disorder. The involvement of different internal organs and systems, such as respiratory, genitourinary, and gastrointestinal systems, has been reported in the literature depending on the type of EB. We report a case of junctional epidermolysis bullosa (JEB) with urogenital involvement in a female child in Pakistan. JEB is a rare subtype of EB which is transmitted in an autosomal recessive pattern of inheritance. It classically affects neonates. Diagnosis is established after clinical examination, and investigations are directed at the exploration of skin lesions such as histopathological and direct immunofluorescence studies. Management of patients is primarily supportive.

Perioperative management of congenital epidermolysis bullosa

Congenital epidermolysis bullosa is a rare disease that causes blister formation in areas susceptible to mechanical stimulation. We present the case of a patient with congenital epidermolysis bullosa simplex who underwent thoracoscopic surgery for pneumothorax. The postoperative course was uneventful, and the patient was discharged on postoperative day 5. Crusts developed around the blistered skin, which normalized within 2 months postoperatively. General anesthesia and skin management are critical in thoracoscopic surgery for patients with congenital epidermolysis bullosa simplex.

Squamous Cell Carcinoma in Patients with Inherited Epidermolysis Bullosa: Review of Current Literature

Epidermolysis bullosa (EB) is a group of rare congenital diseases caused by mutations in structural proteins of the dermal/epidermal junction that are characterized by extreme epithelial fragility, which determines the formation of bullae and erosions either spontaneously or after local mechanical traumas. In EB patients, skin fragility leads to many possible complications and comorbidities. One of the most feared complications is the development of cutaneous squamous cell carcinomas (SCCs) that particularly in the dystrophic recessive EB subtype can be extremely aggressive and often metastatic. SCCs in EB patients generally arise more often in the extremities, where chronic blisters and scars are generally located. SCCs represent a big therapeutic challenge in the EB population. No standard of care exists for the treatment of SCC in these patients, and therapy is based on small case studies. Moreover, the pathogenesis of cSCC in EB patients is still unclear. Many theories have been indeed postulated in order to explain why cSCC behaves so much more aggressively in EB patients compared to the general population. cSCC in EB seems to be the result of many complex interactions among cancer cells, skin microenvironment, susceptibility to DNA mutations and host immune response. In this review, we analyze the different pathogenetic mechanisms of cSCC in EB patients, as well as new therapies for this condition.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Role of dystrophic epidermolysis bullosa in anxiety, depression and self-esteem: A controlled cross-sectional study

The psychological aspect in patients with dystrophic epidermolysis bullosa (DEB) is poorly documented. We sought to determine the role of DEB in anxiety, depression and self-esteem. We conducted a cross-sectional study, collecting data from 27 DEB patients and 26 healthy individuals. DEB patients and healthy controls completed three different psychometric scales for anxiety and depression and one scale for self-esteem. DEB patients and healthy controls were homogeneous for age and sex (P > 0.05), but not for employment, marital status and economic level (P < 0.05). Median values of all psychometric battery scales were not statistically significant between DEB patients and healthy controls, except for Goldberg scale for anxiety (P = 0.003) and depression (P = 0.037) and slightly significant for Zung Scale for anxiety (P = 0.048) with no difference between DEB patients with dominant versus recessive form in all scales (P > 0.05). Among DEB patients, only employment showed a significant difference in all scales (P < 0.05) but Hamilton for depression, whereas self-esteem seemed to be affected by marriage (P = 0.04) and education (P = 0.016). DEB patients apparently are not more anxious and/or depressed and do not have less self-esteem than healthy individuals.

Clinical features of gingival lesions in patients with dystrophic epidermolysis bullosa: a cross-sectional study

BACKGROUND

Gingival lesions in patients with dystrophic epidermolysis bullosa (DEB) are a common manifestation. However, their clinical features, frequency and severity are currently unknown.

METHODS

Forty-five DEB patients were assessed by an oral medicine specialist, who analysed the presence/absence of four clinical signs (erythema, erosion/ulcer, atrophy, blister) on free and attached gingiva, using the Epidermolysis Bullosa Oropharyngeal Severity score.

RESULTS

Twenty-eight (62.2%) out of 45 DEB patients showed different types of gingival lesions, whose presence/absence and total frequency/distribution were not significantly different between males and females (p=0.087 and p=0.091, respectively). Erythema was the most prevalent lesion (66.2%) and the recessive DEB severe generalized (RDEB-sev gen) reached the highest median disease activity score. A significant correlation was observed between the DEB subtypes and the disease activity median score (p<0.001), but not between age and total disease activity score in each group of DEB (p>0.05). Lastly, logistic regression showed that only gender (p=0.031) and RDEB-sev gen (p=0.001) were risks factors for the presence of gingival lesions.

CONCLUSIONS

Gingival lesions in DEB patients are a relatively common entity and may have multiple clinical aspects, emphasizing the need for thorough attention and awareness among dentists.

The regenerative potential of epithelial stem cells in tissue repair

Acute and chronic wounds encompass devastating injuries with significant physical, emotional and economic costs at both the individual and societal level. The pathogenesis of chronic wounds is as varied as the potential causes; however, contributing factors include repetitive ischaemia/reperfusion injury coupled with bacterial infection, inflammation and matrix degradation at the wound site. Similarly, the acute physical damage of burns may leave patients vulnerable to dehydration and infection, and in certain cases this may be followed by a body-wide systemic response with debilitating consequences. Epithelial stem cells provide a promising avenue for the treatment of burns and chronic wounds. This is exemplified by recent achievements such as the restoration of corneal epithelium using limbal stem cells, and the treatment of epidermolysis bullosa via a gene therapy approach. Nevertheless, many technical and regulatory challenges remain to be addressed. This article is part of a Directed Issue entitled: Regenerative Medicine: the challenge of translation.

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.

Genotype-oropharyngeal phenotype correlation in Mexican patients with dystrophic epidermolysis bullosa

Previous investigations have attempted to correlate the genotype with the cutaneous phenotype in patients with epidermolysis bullosa (EB), but never with the oropharyngeal phenotype. Seventeen dystrophic EB (DEB) patients were genotyped for COL7A1 gene mutations and divided into five distinct groups. Oropharyngeal disease severity was assessed with the Epidermolysis Bullosa Oropharyngeal Severity (EBOS) score by an oral medicine specialist. The genotype-phenotype correlation was calculated by Kruskal-Wallis analysis of variance using the Mann-Whitney test, applying the Bonferroni correction. The most severe oropharyngeal phenotype was found in the group with the 2470insG/3948insT mutation, with a mean disease severity score of 18.50 ± 2.12; the mildest was found in the 6862del16 mutation group, with a mean disease severity score of 0.57 ± 1.13. The most significant difference in median score was found in the total score (P = 0.009), followed by tongue (P = 0.02) and upper lip (P = 0.021), but no correlation was found between disease severity and the groups (P>0.005, after Bonferroni correction). Multiple comparisons among the five different genotypic groups revealed no statistically significant genotype-oropharyngeal phenotype correlation; it was not possible to establish which group was more severe, or to associate a specific mutation to a specific oropharyngeal phenotype.

Diagnosing epidermolysis bullosa type and subtype in infancy using immunofluorescence microscopy: the Stanford experience

The natural history of inherited epidermolysis bullosa (EB) varies significantly across subtypes. When confronted with an infant suspected to have EB, rapidly determining the type and subtype is critical in counselling families accurately about the infant's diagnosis and prognosis. Although transmission electron microscopy (TEM) has been considered the criterion standard for EB diagnosis, immunofluorescence microscopy (IFM) using monoclonal antibodies (mAbs) to EB-specific basement membrane zone proteins has several advantages, but few studies have evaluated the diagnostic utility of IFM. We sought to evaluate the clinical utility of IFM using an expanded panel of EB-specific mAbs. This was a retrospective review of pathology reports from infants younger < 1 year old with suspected EB primarily analyzed with IFM by the Stanford Dermatopathology service. Seventy-seven cases were identified for analysis, of which 20 were suboptimal for IFM analysis. Fifty-five cases were diagnosed with EB and classified as follows: EB simplex (n = 5), junctional EB (n = 31), dystrophic EB (n = 19). TEM was available in 36 of 55 cases (65%). IFM with an expanded panel of EB-specific mAbs should be considered the first-line diagnostic test to evaluate infants with clinically suspected EB.

Remodeling of the dermal-epidermal junction in bilayered skin constructs after silencing the expression of the p.R2622Q and p.G2623C collagen VII mutants

The integrity of skin depends on a complex system of extracellular matrix molecules that form a biological scaffold. One of its elements is the dermal basement membrane that provides a link between the epidermis and the dermis. Mutations in collagen VII, a key component of the dermal membrane zone, are associated with dystrophic epidermolysis bullosa. Although it has been proposed that silencing the mutated COL7A1 allele is a promising approach to restore the dermal basement membrane zone formed in the presence of collagen VII mutants, limitations exist to testing this proposal. Here, we employed a model that utilized skin-like constructs in which engineered collagen VII mutant chains harboring the R2622Q or G2623C substitution were expressed conditionally, but the wild-type chains were expressed unconditionally. We demonstrated that switching off the production of the mutant collagen VII chains in skin constructs restores the organization of collagen VII and laminin 332 deposits in the dermal-epidermal junction to the level of control. We also demonstrated that remodeling of collagen IV deposits was not fully effective after silencing the expression of collagen VII mutants. Thus, our study suggests that while silencing mutant alleles of COL7A1 may repair critical elements of the affected dermal basement membrane, it may not be sufficient to fully remodel its entire architecture initially formed in the presence of the mutant collagen VII chains.

The use of cultured allogenic keratinocyte grafting in a patient with epidermolysis bullosa simplex

Epidermolysis bullosa (EB) is a rare genetic disease that is known for continuous skin blistering caused by minor trauma. The skin blisters and bullae that develop often cause skin defects. There is no definitive treatment for EB, only symptomatic relief. We report our experience with cultured allogenic keratinocyte grafting in a newborn patient with EB simplex who had unhealed raw surfaces and was not a skin grafting candidate. The skin lesions of the patient were covered with cultured allogenic keratinocyte grafts and re-epithelialized quickly with no scarring. Allogenic keratinocyte grafting reduced pain and produced noticeable improvements in the unhealed wounds. We think that allogenic keratinocyte grafting can play an important role in the management of patients with EB simplex.

FULL-THICKNESS SKIN GRAFTING IN PSEUDOSYNDACTILY WITH RECESSIVE DYSTROPHIC EPIDERMOLYSIS BULLOSA

Two 17- and 11-year-old brothers appeared with mitten pseudosyndactily of both hands. They have been suffering from recessive dystrophic epidermolysis bullosa with recurrent cutaneous blister formation either spontaneously or due to minor trauma. Surgeries were performed to release and widen the first web space. Full thickness skin graft which was used to cover the resulting raw surface appears stable as normal skin to them. The two brothers have improvement in range of motion of their thumbs and index fingers.

Nexus between epidermolysis bullosa and transcriptional regulation by thyroid hormone in epidermal keratinocytes

Abstract Thyroid hormone, T3, through the interaction of its receptor with the recognition sequences in the DNA, regulates gene expression. This regulation includes the promoter activity of keratin genes. The receptor shares coregulators with other members of the nuclear receptor family, including RXR. Intending to define the transcriptional effects of thyroid hormones in keratinocytes, we used Affymetrix microarrays to comprehensively compare the genes expressed in T3-treated and untreated human epidermal keratinocytes. The transcriptomes were compared at 1, 4, 24, 48, and 72 hours. Surprisingly, T3 induced only 9 and suppressed 28 genes, much fewer than expected. Significantly, genes associated with epidermolysis bullosa, a set of inherited blistering skin diseases, were found statistically highly overrepresented among the suppressed genes. These genes include Integrin beta4, Plectin, Collagen XVII, MMP1, MMP3, and MMP14. The data imply that in keratinocytes T3 could suppresses the remodeling by, attachment to, and production of extracellular matrix. The results suggest that topical treatment with T3 may be effective for alleviation of symptoms in patients with epidermolysis bullosa.

Successful radiation therapy for supratentorial primitive neuroectodermal tumor and epidermolysis bullosa simplex

Epidermolysis bullosa simplex (EBS) is a heritable skin disorder characterized by skin fragility and blistering. While its most severe variant, dystrophic epidermolysis bullosa (DEB) is associated with squamous cell carcinoma (SCC), the development of extracutaneous neoplasms in EBS is extremely rare. We report a novel case of supratentorial primitive neuroectodermal tumor (sPNET) in a 7-year male with EBS. Experience of radiation therapy and its challenges in children with EBS has rarely been reported.

Dressings used in epidermolysis bullosa blister wounds: a review

There is little rigorous evidence on the management of epidermolysis bullosa, so management is based on the patient's and clinician's preferences. However, there is a consensus that advanced dressings help promote healing and reduce pain.

Growth outcomes and complications after radiologic gastrostomy in 120 children

BACKGROUND

Enteral feeding is ideal for children with low caloric intake. It can be provided through different methods, including nasogastric, nasojejunal, gastrostomy, or gastrojejunostomy tubes.

OBJECTIVE

To assess growth outcomes of pediatric patients following retrograde percutaneous gastrostomy (RPG) and compare complications with those following other gastrostomy methods.

MATERIALS AND METHODS

We retrospectively reviewed 120 random RPG patients from 2002 to 2003 (mean follow-up, 2.7 years). Patient weights and growth percentiles were recorded at insertion, and at 0-5 months, 6-12 months, and 18-24 months after insertion, and then compared using a Student's t-test. Complications and tube maintenance issues (TMIs) were recorded.

RESULTS

Gastrostomy tube insertion was successful in all 120 patients (59 boys, 61 girls; mean age 4.3 years). The most common underlying diagnosis was neurologic disease (29%, 35/120) and the main indication was inadequate caloric intake (24%, 29/120). Significant increases in growth percentile for the entire population were demonstrated between insertion and 0-5 months (18.7-25.3; P<0.001) and between insertion and 18-24 months (18.7-25.8; P<0.001). In boys and girls significant growth increases occurred between insertion and 0-5 months (boys P=0.004; girls P=0.01). There were 11 major postprocedural complications, 100 minor complications and 169 TMIs.

CONCLUSION

RPG provides long-term enteral nutrition in the pediatric population and increases growth significantly 6 and 24 months after insertion. Minor complications and TMIs are frequent.

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.

Congenital cerebellar malignant rhabdoid tumor in an infant with junctional epidermolysis bullosa

Epidermolysis bullosa (EB), a hereditary blistering condition of the skin, is divided into simplex, hemidesmosomal, junctional, and dystrophic types. It may be complicated by the development of squamous cell carcinoma of the skin, but other neoplasms, especially those separate from involved skin, are distinctly rare. We report a male infant with junctional EB who died of Pseudomonas sepsis and was found at autopsy to have a clinically unrecognized cerebellar malignant rhabdoid tumor (MRT). This is the first reported case of an infant with EB and a coincident extracutaneous neoplasm. It is also the first known case of EB associated with a pathologically confirmed malignant brain tumor. Cytogenetic results from the infant and his tumor and both of his parents suggest the infant's EB and MRT were not genetically linked.

Nutritional support for children with epidermolysis bullosa

Epidermolysis bullosa (EB) comprises a rare group of genetically determined skin blistering disorders characterized by extreme fragility of the skin and mucous membranes, with recurrent blister formation. The cornerstones of management are control of infection, wound management, pain relief, promotion of optimal nutritional status and mobility, surgical intervention and provision of the best possible quality of life. There is currently no cure for EB and, throughout life, those with the more severe types are at risk of significant nutritional compromise which impacts negatively on health and overall quality of life. Nutritional support is an important facet of holistic care and the dietetic challenges can be considerable. This paper describes some of the issues involved in optimizing the nutritional status of children with this disorder.

Junctional epidermolysis bullosa

Epidermolysis bullosa (EB) encompasses a heterogeneous group of genodermatoses, characterized by fragility and blistering of the skin, often associated with extracutaneous manifestations. The level of vesiculation within the skin defines 3 major subtypes of EB: EB simplex, junctional EB, and dystrophic EB. We present the case of a male neonate of 36 weeks of gestation, who was born with a few blisters with erosions and who rapidly developed extensive blistering of the skin. Histopathology revealed subepidermal blistering. Electron microscopy confirmed the cleavage of epidermis from dermis within the lamina lucida. Junctional EB was the diagnosis. The patient was discharged after hospitalization for 28 days. The development of new blisters with erosions were gradually improved after AQUACEL Ag dressing, and the general condition was much better than at admission. The patient likely has a subtype of junctional EB termed generalized atrophic benign EB that clinically improves with age. He has the potential to father children and has a normal life expectancy.

Using Urgotul dressing for the management of epidermolysis bullosa skin lesions

OBJECTIVE

To evaluate the acceptability, tolerance and efficacy of Urgotul wound dressing in the management of epidermolysis bullosa (EB) skin lesions.

METHOD

This was an open-label uncontrolled clinical trial involving 20 patients (I I adults and nine children) with EB simplex or dystrophic EB. Patients were selected from the register of EB patients at the investigating centre and included if they presented with at least one skin lesion requiring management with a non-adherent wound dressing. Lesions were treated with the study dressing for a maximum of four weeks. All dressing changes, wound parameters, pain and effect on quality of life were recorded.

RESULTS

All patients completed the trial. Nineteen out of 20 wounds healed within 8.7 +/- 8.5 days. Overall, 11 patients (55%) considered that their quality of life had improved following use of the dressing, which was also reported to be pain free and 'very easy' or 'easy' to remove at most dressing changes. Nineteen out of 20 patients stated that they would use the study dressing to manage their lesions in future.

CONCLUSION

This study confirmed the very good acceptability and efficacy of Urgotul in the treatment of skin lesions in patients with EB.

Epidermólise bolhosa distrófica recessiva mitis: relato de caso clínico

As epidermólises bolhosas são dermatoses bolhosas congênitas que levam à formação de bolhas espontaneamente ou após trauma. São reconhecidos três grupos de da doença, de acordo com o segundo consenso internacional: simples, juncional e distrófica. Nas formas distróficas, o defeito genético deve-se à mutação no gene COL7A1, responsável pela codificação do colágeno VII, principal constituinte das fibrilas de ancoragem, que participam na aderência da lâmina densa à derme. Os autores relatam o caso de paciente do sexo feminino, de 15 anos, apresentando ulcerações nas pernas, bolhas serosas e lesões atrófico-acastanhadas nos braços e tronco. Foram observadas distrofias ungueais e alterações dentárias, iniciadas a partir do nascimento. O exame histopatológico da bolha revelou quadro compatével com epidermólise bolhosa, que, associado aos dados clínicos, permitiram a classificação do caso na forma distrófica recessiva mitis.

Ocular Surface Findings in Hallopeau-Siemens Subtype of Dystrophic Epidermolysis Bullosa

PURPOSE

This article describes the clinical features and long-term changes in corneal sensitivity, tear function, and impression cytology findings in a patient with recessive dystrophic epidermolysis bullosa (DEB).

METHODS

The patient underwent best-corrected Landolt visual acuity measurements, slit-lamp examinations, anterior segment photography, Schirmer test with anesthesia, tear film break-up time, corneal fluorescein and Rose-Bengal staining, assessment of corneal sensitivity, and conjunctival impression cytology at the initial and final visits.

RESULTS

The patient had a recurrent corneal erosion in the right eye and a painful corneal blister with extensive superficial punctuate keratopathy in the left eye, which remained refractory to treatment with patching, lubricants, and antibiotic ointments for 10 weeks. The corneal disease in both eyes responded swiftly to topical fibronectin, topical nonpreserved tears, vitamin A ointment, and therapeutic soft contact lenses. Maintenance treatment was continued with preservative-free topical tear drops and vitamin A ointment. Corneal disease did not recur in the patient during the follow-up of 29 months. The mean corneal sensitivity and tear film break-up time were decreased initially in both eyes and attained normal values with treatment. Impression cytology revealed squamous metaplasia, loss of cellular cohesion, and total absence of goblet cells before treatment, all of which were observed to be normalized at the final follow-up.

CONCLUSIONS

The ocular surface disease in DEB was characterized by low corneal sensitivity, disorder of tear quality, decreased cellular cohesion, squamous metaplasia of the conjunctiva, and goblet cell loss. Close follow-up for ocular complications in DEB is essential and a pathophysiology-oriented approach to the epithelial disease may not only provide rapid healing but might prevent recurrences as well.

Translational benefits from research on rare genodermatoses

Significant new discoveries about many of the genodermatoses have been made recently through an improved knowledge of the human genome, advances in molecular screening strategies and also through more comprehensive Internet DNA databases. By 2003, over 350 single gene skin disorders had been characterized at a molecular level. These new data provide more detailed information for patients, allow for more accurate diagnoses, and help improve genetic counselling. Other benefits include the feasibility of carrier screening and DNA-based prenatal testing, as well as a platform for devising new treatments, including somatic gene therapy. Research on rare single gene disorders also provides new insight into more common skin conditions. For example, new ideas about photosensitivity are emerging from discoveries of mutations in a novel component of the actin cytoskeleton (kindlin-1) in the rare inherited poikiloderma disorder, Kindler syndrome. Likewise, new clues to understanding disease pathology in lichen sclerosus have been gleaned from the discovery of pathogenic mutations in the skin protein, extracellular matrix protein 1, in the rare sclerosing inherited skin disorder, lipoid proteinosis. Finally, new insight into what can cause exuberant granulation tissue in chronic wounds has been provided by the discovery of specific mutations in the basement membrane protein, laminin 5, in the rare inherited condition, laryngo-onychocutaneous syndrome. It is clear that a precise research focus on the rare genodermatoses is providing practical benefits for sufferers of these disorders, as well as new lessons and ideas about more common acquired skin conditions.