Dystrophic epidermolysis bullosa associated with eosinophilic infiltrate and elevated serum IgE

Efficacy of oral JAK1 or JAK1/2 inhibitor for treating refractory pruritus in dystrophic epidermolysis bullosa: A retrospective case series

Refractory pruritus is the most distressing, disease-related symptom in patients with dystrophic epidermolysis bullosa (DEB), inducing an itch-scratch-blister cycle. Chronic inflammation is a hallmark of DEB, thus upregulation of inflammatory cytokines and Janus kinase (JAK) signaling may play a role in DEB-related pruritus. We retrospectively reviewed the medical records of DEB patients with refractory pruritus who were treated with either baricitinib, a JAK1/2 inhibitor, or upadacitinib, a selective JAK1 inhibitor. Patients received baricitinib (4 mg) or upadacitinib (15 mg) once a day for 2-32 weeks. A total of 12 DEB patients (six recessive DEB and six dominant DEB) were included in this study. The mean±SD baseline pruritus visual analog scale (VAS) score was 7.5 ± 1.7. Upadacitinib or baricitinib treatment resulted in a rapid and sustained decrease in itch. Four out of 12 patients (33.3%) and seven out of 10 patients (70%) showed a decrease of at least 3 points in the pruritus VAS score from baseline at weeks 2 and 4, respectively. The mean percentage changes from baseline in pruritus VAS scores at weeks 2 and 4 were -42.9% and -52.7%, respectively. Subgroup analysis showed greater reductions in the pruritus VAS score in the baricitinib group (n = 5) compared to the upadacitinib group (n = 7), and in patients with epidermolysis bullosa pruriginosa (n = 3) compared to other subtypes of DEB (n = 9); however, these differences did not reach statistical significance. Three out of 10 (33.3%) patients showed at least a 2-point reduction in pain intensity from baseline at week 4. Eight out of 12 patients (66.7%) also showed a reduction in the number of new blisters, which correlated with a reduction in the pruritus score. No patient discontinued treatment because of serious adverse events. Our results suggest that JAK1 or JAK1/2 inhibitors could be a promising treatment option for DEB-related pruritus. Long-term safety should be assessed in future studies.

Pruritus Anesis in Dystrophic Epidermolysis Bullosa Pruriginosa with Dupilumab

ABSTRACT

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

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

BACKGROUND

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSION

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

The clinical efficacy and safety of anti-IgE therapy in recessive dystrophic epidermolysis bullosa

The treatment of recessive dystrophic epidermolysis bullosa (RDEB) remains challenging. Elevated IgE levels have previously been reported in several RDEB patients. In this prospective, single-centre, open intervention study, elevated IgE levels were seen in 11 out of 12 patients with intense pruritus, and the patients with elevated IgE levels received anti-IgE therapy every 4 weeks for at least three cycles. Compared with the baseline, 10 patients with RDEB had good clinical outcomes with enhanced wound healing, a reduction in Birmingham (epidermolysis bullosa) EB severity score by 15%, a reduction in affected body surface area by 23.3%, amelioration of skin inflammation, and an increase in type VII collagen deposition by 13.1-fold. All the patients had a good tolerance to anti-IgE therapy. Furthermore, patients with higher IgE levels tended to have higher disease severity and more favorable clinical outcomes. Our report also suggested the potential role of IgE in the pathogenesis of inflammatory conditions associated with RDEB. (ChiCTR1900021437).

A Review of Acquired Autoimmune Blistering Diseases in Inherited Epidermolysis Bullosa: Implications for the Future of Gene Therapy

Gene therapy serves as a promising therapy in the pipeline for treatment of epidermolysis bullosa (EB). However, with great promise, the risk of autoimmunity must be considered. While EB is a group of inherited blistering disorders caused by mutations in various skin proteins, autoimmune blistering diseases (AIBD) have a similar clinical phenotype and are caused by autoantibodies targeting skin antigens. Often, AIBD and EB have the same protein targeted through antibody or mutation, respectively. Moreover, EB patients are also reported to carry anti-skin antibodies of questionable pathogenicity. It has been speculated that activation of autoimmunity is both a consequence and cause of further skin deterioration in EB due to a state of chronic inflammation. Herein, we review the factors that facilitate the initiation of autoimmune and inflammatory responses to help understand the pathogenesis and therapeutic implications of the overlap between EB and AIBD. These may also help explain whether corrections of highly immunogenic portions of protein through gene therapy confers a greater risk towards developing AIBD.

Prevalence, pathophysiology and management of itch in epidermolysis bullosa

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

Dermal eosinophilic infiltrate in junctional epidermolysis bullosa

Junctional epidermolysis bullosa (JEB) is a rare genodermatosis characterized by a split in the lamina lucida usually because of mutations in LAMA3, LAMB3 and LAMC2 resulting in absence or reduction of laminin-332. Rare subtypes of JEB have mutations in COL17A1, ITGB4, ITGA6 and ITGA3 leading to reduction or dysfunction of collagen XVII, integrin α6β4 and integrin α3. The classic finding under light microscopy is a paucicellular, subepidermal split. We describe the unusual presence of an eosinophilic infiltrate in the bullae and subjacent dermis in a neonate with JEB, generalized intermediate (formerly known as non-Herlitz-type JEB), discuss the histologic differential diagnosis for a subepidermal blister in a neonate, review the literature regarding cases of epidermolysis bullosa (EB) presenting with inflammatory infiltrates, and discuss mechanisms to explain these findings. This case highlights that eosinophils can rarely be seen in EB and should not mislead the dermatopathologist into diagnosing an autoimmune blistering disorder.

Burden of itch in epidermolysis bullosa

BACKGROUND

Itch is an unpleasant feeling that leads to scratching. It is a common, but understudied, problem in patients with epidermolysis bullosa (EB).

OBJECTIVES

We measured the prevalence and characteristics of itch in the three major forms of EB: generalized EB simplex (EBS), junctional EB (JEB) and dystrophic EB (DEB).

METHODS

Forty patients with EB were recruited from two tertiary care centres and one patient organization. The sample included 19 patients with EBS, seven with JEB and 14 with DEB. Patients completed the Leuven Itch Scale (LIS), a multidimensional self-report instrument that quantifies the frequency, duration, severity, distress, consequences and surface area of itch. This instrument has good clinimetric properties.

RESULTS

Itch occurred in 85% of the patients, with substantial differences across the subtypes (EBS 74%, JEB 100%, DEB 93%). Itch, in all its dimensions, was most pronounced in patients with JEB and DEB, and less prominent in patients with EBS. The scores were significantly different for itch frequency, severity, distress and surface area, and the overall itch scores were comparable with those of atopic dermatitis. Itch mainly occurred in a hot environment (65%) and when sweating (62%). The most prevalent consequences were difficulty in falling asleep (88%) and lesions from scratching (85%). Differences between the three major subtypes were also observed in terms of circumstances, consequences and sensory characteristics.

CONCLUSIONS

As expected, itch is common among patients with EB. All aspects of itch measured by the LIS were more severe in JEB and DEB than in EBS.

Oral steroid improves bullous pemphigoid-like clinical manifestations in non-Herlitz junctional epidermolysis bullosa with COL17A1 mutation

Non-Herlitz junctional epidermolysis bullosa (JEB-nH), a nonlethal variant of junctional epidermolysis bullosa (JEB), is an autosomal recessive disorder characterized by separation of the dermal-epidermal junction. JEB-nH is caused by mutations in several genes and lack of the COL17A1 gene product may lead to skin fragility. A 41-year-old Japanese man with JEB-nH, featuring mutations in the gene encoding type XVII collagen, presented with great blisters over his entire body accompanied by severe itching and eosinophilia usually observed in bullous pemphigoid (BP). To our knowledge, our patient is the first with JEB-nH to be treated successfully with an oral steroid to control his skin affliction, symptoms and eosinophilia. This suggests that in the case of JEB-nH with eosinophilia caused by some secondary immune activation, oral steroids may constitute an alternate therapy to improve aggravated skin conditions and severe itching, both of which tend to show resistance to usual dermatological treatments.

Clinical and molecular dilemmas in the diagnosis of familial epidermolysis bullosa pruriginosa

Dystrophic epidermolysis bullosa is a rare and clinically heterogeneous mechanobullous disorder. One unusual clinical variant is epidermolysis bullosa pruriginosa (EBP), in which the combination of pruritus and skin fragility can lead to hypertrophic, lichenified nodules and plaques. This form of inherited epidermolysis bullosa may not develop clinically until adult life, leading to diagnostic confusion with acquired disorders, such as nodular prurigo, lichen simplex, lichen planus, hypertrophic scarring, or dermatitis artefacta. As in all other forms of dystrophic epidermolysis bullosa, the molecular pathology involves mutations in the gene encoding the anchoring fibril protein, type VII collagen (COL7A1), but there is no clear genotype-phenotype correlation in EBP. In this report, we describe a Chinese-Singaporean family with EBP in whom an autosomal dominant glycine substitution mutation, p.G2251E, was identified in exon 86 of the COL7A1 gene. This heterozygous mutation was identified in the genomic DNA of all 4 affected adults tested, as well as 2 clinically unaffected offspring (aged 9-29 years). Based on DNA sequencing, we predict that these individuals may develop EBP later in life, although additional factors leading to disease expression may determine phenotypic expression. Nevertheless, we plan to closely monitor these potentially presymptomatic individuals for symptoms of pruritus and early signs of the genetic disorder.

Bullous dermatoses in childhood: part II

Bullous dermatoses are commonly encountered in childhood practice. Much confusion exists among clinicians because of the similarity of clinical lesions, paucity of relevant literature, and varied nomenclature used for these diseases. For a better understanding of the proposed classification, this second part is a review of diseases with nonhereditary characteristics of subepidermal cleavage and hereditary characteristics with intraepidermal and subepidermal cleavage.

Eosinophil infiltration in three patients with generalized atrophic benign epidermolysis bullosa from a Japanese family: molecular genetic and immunohistochemical studies

Generalized atrophic benign epidermolysis bullosa (GABEB), a subtype of epidermolysis bullosa (EB), is an autosomal recessive skin disease characterized by derm-epidermal separation leading to skin fragility and atrophy and other associated abnormalities. Although a few reports demonstrated that eosinophils are infiltrating beneath bullas in infants with some types of EB, no such condition in adult GABEB patients has been known. Here we report on three adult patients with GABEB from a Japanese family, whose bullous skin lesions showed massive eosinophil infiltration. One of the three patients showed amyloid deposition at the intestine, kidney, and skin. Linkage analysis revealed that GABEB in the family was linked to COL17A1 with a maximum LOD score of 3.08. Mutation analysis identified in the three patients a homozygous insertional mutation, 209-210insCA, in exon 5 of COL17A1. The expression of mutated COL17A1 was confirmed by semiquantitative RT-PCR, but no signals for truncated COL17A1 protein were detected by the immunohistochemical studies using antibodies against BP180. Furthermore, no autoantibody against the mutant protein was detected by western blot analysis. It is thus less likely that autoantibody and/or a local immune reaction in their skin has a primary role in eosinophil infiltration in these patients.