Clinical characteristics associated with increased wound size in patients with recessive dystrophic epidermolysis bullosa.

As more therapeutic clinical trials focus on treatment of individual wounds in patients with recessive dystrophic epidermolysis bullosa, it has become crucial to understand the baseline clinical characteristics of these wounds. To investigate these features, we administered an RDEB-specific wound survey. Forty participants reported on location, size, pain, infection frequency, wound type, and duration of 189 wounds; a subset of 22 participants reported on pruritus in 63 wounds. Increased wound size was significantly associated with increased pain, increased pruritus, longer wound duration, increased infection frequency, and patients with mutations resulting in truncated type VII collagen.

Patient-reported outcomes and quality of life in recessive dystrophic epidermolysis bullosa: A global cross-sectional survey.

BACKGROUND: A spectrum of skin disease severity exists in patients with recessive dystrophic epidermolysis bullosa (RDEB). OBJECTIVE: To characterize the patient-reported outcomes and quality of life (QOL) in patients with RDEB. METHODS: A cross-sectional study of patients with RDEB surveyed through the global EBCare Registry. Patient-reported outcomes included skin disease severity, wound characteristics, pain, itch, extracutaneous symptoms, and medications. QOL was measured by using the validated Quality of Life in Epidermolysis Bullosa instrument. RESULTS: A total of 85 patients with RDEB reported 1226 wounds (937 recurrent wounds and 289 chronic open wounds). Overall skin disease severity was self-reported as mild (26%; 22/83), moderate (48%; 40/83), or severe (25%; 21/83). Worsening skin disease severity was significantly associated with larger wounds, increased opiate use, anemia, gastrostomy tube use, infections, osteoporosis, and squamous cell carcinoma. Larger wound size was associated with worse quality of life scores. LIMITATIONS: All data were self-reported from an online epidermolysis bullosa patient registry. CONCLUSIONS: This study shows a significant correlation between larger wound size with worsening skin disease severity and quality of life in participants with RDEB. Worsening skin disease severity significantly correlated with key clinical manifestations. These results show that patients with RDEB are able to self-report their skin disease severity and wounds.

Phase 2 trial of a neurokinin-1 receptor antagonist for the treatment of chronic itch in patients with epidermolysis bullosa: A randomized clinical trial.

BACKGROUND: Chronic pruritus causes major morbidity in epidermolysis bullosa (EB). The substance P-neurokinin 1 receptor (SP-NK1) pathway is a promising target for treating EB-related pruritus. OBJECTIVE: To evaluate the safety and efficacy of the oral NK1 receptor antagonist serlopitant in treating moderate-severe pruritus in EB. METHODS: The study randomized 14 patients to serlopitant or placebo for 8 weeks, followed by a 4-week washout and optional open-label extension. The primary end point was change in itch as measured by the Numeric Rating Scale. Secondary end points were change in itch during dressing changes and wound size. RESULTS: We observed greater itch reduction with serlopitant, equivalent to a 0.64-point comparative reduction on the 11-point Numeric Rating Scale by week 8, although this failed to meet statistical significance (P = .11). More serlopitant patients achieved ≥3-point reduction compared with placebo (43% vs 14%, P = .35). In post hoc analysis excluding 1 patient with a concurrent seborrheic dermatitis flare, serlopitant achieved significantly greater median itch reduction from baseline by week 4 (-2 points vs 0, P = .01). We observed no statistically significant differences in secondary end points. Serlopitant was well-tolerated. LIMITATIONS: Small sample size due to disease rarity. CONCLUSION: The potential itch reduction with serlopitant observed in this trial will be pursued by a larger powered trial (NCT03836001).

From Clinical Phenotype to Genotypic Modelling: Incidence and Prevalence of Recessive Dystrophic Epidermolysis Bullosa (RDEB).

BACKGROUND: Recessive dystrophic epidermolysis bullosa (RDEB) is an inherited genetic disorder characterized by recurrent and chronic open wounds with significant morbidity, impaired quality of life, and early mortality. RDEB patients demonstrate reduction or structural alteration type VII collagen (C7) owing to mutations in the gene COL7A1, the main component of anchoring fibrils (AF) necessary to maintain epidermal-dermal cohesion. While over 700 alterations in COL7A1 have been reported to cause dystrophic epidermolysis bullosa (DEB), which may be inherited in an autosomal dominant (DDEB) or autosomal recessive pattern (RDEB), the incidence and prevalence of RDEB is not well defined. To date, the widely estimated incidence (0.2-6.65 per million births) and prevalence (3.5-20.4 per million people) of RDEB has been primarily characterized by limited analyses of clinical databases or registries. METHODS: Using a genetic modelling approach, we use whole exome and genome sequencing data to estimate the allele frequency of pathogenic variants. Through the ClinVar and NCBI database of human genome variants and phenotypes, DEB Register, and analyzing premature COL7A1 termination variants we built a model to predict the pathogenicity of previously unclassified variants. We applied the model to publicly available sequences from the Exome Aggregation Consortium (ExAC) and Genome Aggregation Database (gnomAD) and identified variants which were classified as pathogenic for RDEB from which we estimate disease incidence and prevalence. RESULTS: Genetic modelling applied to the whole exome and genome sequencing data resulted in the identification of predicted RDEB pathogenic alleles, from which our estimate of the incidence of RDEB is 95 per million live births, 30 times the 3.05 per million live birth incidence estimated by the National Epidermolysis Bullosa Registry (NEBR). Using a simulation approach, we estimate a mean of approximately 3,850 patients in the US who may benefit from COL7A1-mediated treatments in the US. CONCLUSION: We conclude that genetic allele frequency estimation may enhance the underdiagnosis of rare genetic diseases generally, and RDEB specifically, which may improve incidence and prevalence estimates of patients who may benefit from treatment.

Risk Factors for Basal Cell Carcinoma Among Patients With Basal Cell Nevus Syndrome: Development of a Basal Cell Nevus Syndrome Patient Registry.

IMPORTANCE: Patients with basal cell nevus syndrome (BCNS) have a greater risk of developing numerous basal cell carcinomas (BCCs). Risk factors influencing the wide variation in tumor burden are poorly understood. OBJECTIVE: To describe the burden of BCCs in patients with BCNS in the United States and identify potential risk factors for BCCs. DESIGN, SETTING, AND PARTICIPANTS: Prospective clinical registry with data collected from September 2014 to March 2016. Participants were recruited from a mailing list of patients with BCNS at Children's Hospital Oakland Research Institute and Basal Cell Carcinoma Nevus Syndrome Life Support Network. Patients of all ages with a diagnosis of BCNS were eligible for enrollment. Participants completed a clinical questionnaire on their disease characteristics and risk factors. MAIN OUTCOMES AND MEASURES: Number of BCCs in the past 2 years and over lifetime (disease burden), risk factors for BCCs. RESULTS: A consecutive sample of the first 141 participants was included (34% [100 of 297] response rate from paper survey, 23% [41 of 179] from online survey; 85 [60%] female; mean age at start of study, 53 [range, 8-83] years; 131 [93%] white). In the previous 2 years, participants reported a mean of 25 BCCs (median, 11; range, 0-250). Over their lifetime, participants reported a mean of 257 BCCs (median, 160; range, 0-2200). Univariate analysis identified age (odds ratio [OR], 1.05; 95% CI, 1.03-1.07; P < .001), number of sunburns (OR, 1.05; 95% CI, 1.00-1.10; P = .047), and history of radiation exposure (OR, 2.26; 95% CI, 1.02-5.03; P = .046) as potential risk factors for lifetime BCC severity. On multivariate analysis, only age (OR, 1.04; 95% CI, 1.02-1.07; P < .001) and number of sunburns (OR, 1.06; 95% CI, 1.00-1.11; P = .04) were statistically significant. In our adjusted models, BCC burden increased by 4% per year of age and by 6% per number of sunburns. CONCLUSIONS AND RELEVANCE: Patients with BCNS have a high burden of BCCs. Age and number of sunburns were significantly associated with the severity of lifetime BCC. Further interventions to prevent and treat BCCs in patients with BCNS are needed.

Characterization of an animal model of aggressive metastatic pheochromocytoma linked to a specific gene signature.

Pheochromocytomas are chromaffin cell-derived neuroendocrine tumors. There is presently no cure for metastatic pheochromocytoma and no reliable way to distinguish malignant from benign tumors before the development of metastases. In order to successfully manage pheochromocytoma, it is necessary to better understand the biological determinants of tumor behavior. For this purpose, we have recently established a mouse model of metastatic pheochromocytoma using tail vein injection of mouse pheochromocytoma (MPC) cells. We optimized this model modifying the number of cells injected, length of trypsin pre-treatment, and incubation temperature and duration for the MPC cells before injection, and by serial passage and re-selection of tumors exhibiting the metastatic phenotype. We evaluated the effect of these modifications on tumor growth using serial in vivo Magnetic Resonance Imaging studies. These results show that number of cells injected, the pre-injection incubation temperature, and duration of trypsin treatment are important factors to produce faster growing, more aggressive tumors that yielded secondary metastatic lesions. Serial harvest, culture and re-selection of metastatic liver lesions produced even more aggressive pheochromocytoma cells that retained their biochemical phenotype. Microarray gene expression comparison and quantitative real-time PCR of these more aggressive cells to the MPC-parental cell line identified genes that may be important for the metastatic process.