Functional genotype-phenotype associations in recessive dystrophic epidermolysis bullosa.

BACKGROUND: Genotype-phenotype associations in recessive dystrophic epidermolysis bullosa (RDEB) have been difficult to elucidate. OBJECTIVE: To investigate RDEB genotype-phenotype associations and explore a functional approach to genotype classification. METHODS: Clinical examination and genetic testing of RDEB subjects, including assessment of clinical disease by RDEB subtype and extent of blistering. Genotypes were evaluated according to each variant's effect on type VII collagen function per updated literature and subsequently categorized by degree of impact on VII collagen function as low-impact (splice/missense, missense/missense), medium-impact (premature termination codon [PTC]/missense, splice/splice), and high-impact (PTC/PTC, PTC/splice). Genotype-phenotype associations were investigated using Kruskal-Wallis and Fisher's exact tests, and age-adjusted regressions. RESULTS: Eighty-three participants were included. High-impact variants were associated with worse RDEB subtype and clinical disease, including increased prevalence of generalized blistering (55.6% for low-impact vs 72.7% medium-impact vs 90.4% high-impact variants, P = .002). In age-adjusted regressions, participants with high-impact variants had 40.8-fold greater odds of squamous cell carcinoma compared to low-impact variants (P = .02), and 5.7-fold greater odds of death compared to medium-impact variants (P = .05). LIMITATIONS: Cross-sectional design. CONCLUSION: Functional genotype categories may stratify RDEB severity; high-impact variants correlated with worse clinical outcomes. Further validation in larger cohorts is needed.

Mitochondrial calcium signaling mediated transcriptional regulation of keratin filaments is a critical determinant of melanogenesis.

Mitochondria are versatile organelles that regulate several physiological functions. Many mitochondria-controlled processes are driven by mitochondrial Ca2+ signaling. However, role of mitochondrial Ca2+ signaling in melanosome biology remains unknown. Here, we show that pigmentation requires mitochondrial Ca2+ uptake. In vitro gain and loss of function studies demonstrated that Mitochondrial Ca2+ Uniporter (MCU) is crucial for melanogenesis while the MCU rheostats, MCUb and MICU1 negatively control melanogenesis. Zebrafish and mouse models showed that MCU plays a vital role in pigmentation in vivo. Mechanistically, MCU controls activation of transcription factor NFAT2 to induce expression of three keratins (keratin 5, 7 and 8), which we report as positive regulators of melanogenesis. Interestingly, keratin 5 in turn modulates mitochondrial Ca2+ uptake thereby this signaling module acts as a negative feedback loop that fine-tunes both mitochondrial Ca2+ signaling and melanogenesis. Mitoxantrone, an FDA approved drug that inhibits MCU, decreases physiological melanogenesis. Collectively, our data demonstrates a critical role for mitochondrial Ca2+ signaling in vertebrate pigmentation and reveal the therapeutic potential of targeting MCU for clinical management of pigmentary disorders. Given the centrality of mitochondrial Ca2+ signaling and keratin filaments in cellular physiology, this feedback loop may be functional in a variety of other pathophysiological conditions.

Oral Propranolol Therapy for Infantile Hemangioma: Long-term Follow-up.

ß-blocker therapy is currently the treatment of choice for infantile hemangiomas (IH), albeit with limited data on long-term treatment outcomes. Herein, authors treated 67 IH lesions in 47 patients with oral propranolol at 2 mg/kg/d for a median of 9 mo and followed them up for a median of 48 mo. While no maintenance therapy was required for 18 lesions (26.9%), the rest needed maintenance therapy. Both treatment regimens had comparable efficacy (83.3±23.9% and 92.0±13.8%) but chances of IH recurrence was higher in lesions requiring maintenance therapy. Also, patients treated at ≤5 mo of age had a significantly better response and a lower recurrence rate than patients treated at >5 mo of age (95.0±7.9% vs. 87.0±17.5%, p = 0.05). Authors' experience suggests that longer durations of maintenance therapy offered no added advantage to the overall improvement of IH while treatment initiation at an earlier age showed better improvement and lower recurrence rates.

In vivo topical gene therapy for recessive dystrophic epidermolysis bullosa: a phase 1 and 2 trial.

Recessive dystrophic epidermolysis bullosa (RDEB) is a lifelong genodermatosis associated with blistering, wounding, and scarring caused by mutations in COL7A1, the gene encoding the anchoring fibril component, collagen VII (C7). Here, we evaluated beremagene geperpavec (B-VEC), an engineered, non-replicating COL7A1 containing herpes simplex virus type 1 (HSV-1) vector, to treat RDEB skin. B-VEC restored C7 expression in RDEB keratinocytes, fibroblasts, RDEB mice and human RDEB xenografts. Subsequently, a randomized, placebo-controlled, phase 1 and 2 clinical trial (NCT03536143) evaluated matched wounds from nine RDEB patients receiving topical B-VEC or placebo repeatedly over 12 weeks. No grade 2 or above B-VEC-related adverse events or vector shedding or tissue-bound skin immunoreactants were noted. HSV-1 and C7 antibodies sometimes presented at baseline or increased after B-VEC treatment without an apparent impact on safety or efficacy. Primary and secondary objectives of C7 expression, anchoring fibril assembly, wound surface area reduction, duration of wound closure, and time to wound closure following B-VEC treatment were met. A patient-reported pain-severity secondary outcome was not assessed given the small proportion of wounds treated. A global assessment secondary endpoint was not pursued due to redundancy with regard to other endpoints. These studies show that B-VEC is an easily administered, safely tolerated, topical molecular corrective therapy promoting wound healing in patients with RDEB.

Impact of a Psychodermatological Education Package on the Subjective Distress, Family Burden, and Quality of Life among the Primary Caregivers of Children Affected with Epidermolysis Bullosa.

BACKGROUND: Epidermolysis bullosa (EB) has profound effect on the subjective distress, family burden, and quality of life (QOL) of the primary caregivers (PCG). Knowledgeable PCG can efficiently manage children with these skin diseases and also improve their QOL. OBJECTIVES: To assess the subjective distress, family burden, and QOL, to develop and assess the short-term effectiveness of a psycho-dermatological education package (PDEP) for the PCG of children with EB. METHODS: In this interventional study, 30 PCG of EB were assessed for subjective distress, family burden, and QOL. PDEP, a structured educational tool explaining the disease and its care and stress management, was developed by the authors for the PCG and administered to them after one month of enrolment. They were reassessed after three months and compared with the baseline assessment scores. For comparison, 37 PCG of CI were also studied. RESULTS: The mean age (years) of the subjects was 28.7 ± 6.7 for EB and 30.5 ± 4.6 for CI. The mean or median (range) baseline scores for subjective distress, family burden and QOL of PCG (n = 20) of EB were 8.4 ± 7.9, 6.5 (0-30); 28.5 ± 17.5, 24 (7-77) and 12.6 ± 6.7, 11.5 (4-28) and for PCG (n = 14) of CI were 12 ± 4.3, 38.9 ± 16.2 and 17.7 ± 3.6 respectively. The PDEP improved the QOL (p = 0.01), knowledge (p < 0.01) and practices (p < 0.001) for PCG of EB and it improved subjective distress (p < 0.001), QOL (p < 0.01) and knowledge (p < 0.01) for PCG of CI. CONCLUSIONS: PDEP is an effective educational tool in improving the QOL and knowledge of PCG, which in turn provides efficient management and psychological support to children affected with EB and CI. It should, therefore, be routinely used for educating the PCG of children with EB and CI.

Genotype-Phenotype Correlations of Dystrophic Epidermolysis Bullosa in India: Experience from a Tertiary Care Centre.

Recent advances in the field of genomics have seen the successful implementation of whole exome sequencing as a rapid and efficient diagnostic strategy in several genodermatoses. The aim of this study was to explore the potential of molecular studies in dystrophic epidermolysis bullosa (DEB) in India. Whole exome sequencing was performed using genomic DNA from each case of epidermolysis bullosa, followed by massively parallel sequencing. Resulting reads were mapped to the human reference genome hg19. Sanger sequencing subsequently confirmed the potentially pathogenic mutations. Whole exome sequencing of 18 patients with DEB from 17 unrelated Indian families revealed 20 distinct sequence variants in the COL7A1 gene including 2 widely prevalent mutations. Dominant inheritance was seen in 7 patients, while 11 patients showed a highly variable recessive DEB. This preliminary study using exome sequencing is clearly encouraging and will serve as the basis for future large-scale molecular studies to actively identify and understand DEB in the Indian population.

Application of whole exome sequencing in elucidating the phenotype and genotype spectrum of junctional epidermolysis bullosa: A preliminary experience of a tertiary care centre in India.

BACKGROUND: Junctional epidermolysis bullosa (JEB) is a diverse group of genodermatoses associated with extreme skin fragility. Despite several well-characterized genetic studies, molecular diagnosis of this heterogeneous group is still challenging. Recent advances in the field of genomics have seen the successful implementation of whole exome sequencing (WES) as a fast and efficient diagnostic strategy in several genodermatoses. OBJECTIVE: In view of the scarcity and need of molecular studies for JEB in India, we sought to explore the potential of WES in understanding the mutational spectrum of this rare, in certain subtypes lethal, sub-group of EB. METHODS: WES was performed using genomic DNA from each case of EB, followed by massively parallel sequencing. Resulting reads were mapped to the human reference genome hg19. Sanger sequencing subsequently confirmed the potentially pathogenic mutations. RESULTS: Overall, four unrelated families (6 patients) of JEB with a highly variable clinical presentation including a rare case of LOC syndrome were studied. WES revealed 4 variations in 3 genes (LAMA3, LAMB3 and COL17A1) that are implicated in JEB. None of the variations were recurrent. In addition we proposed the probable molecular consequence of a missense mutation on the structure-function relationship of lamininß3 protein through computational modeling studies. CONCLUSIONS: Being the first report documenting the phenotype-genotype correlations of JEB patients from India, our preliminary experience with WES is clearly encouraging and serves as a nidus for future large-scale molecular studies to actively identify and understand JEB patients in Indian population.

Efficacy of micellized vs. fat-soluble vitamin D3 supplementation in healthy school children from Northern India.

BACKGROUND: Vitamin D deficiency is a widely recognized public health problem. Efficacy of a recently developed micellized form of vitamin D3 has not been studied. Hence, we undertook this study to compare its efficacy with the conventionally used fat-soluble vitamin D3. METHODS: In this open-labeled nonrandomized pilot study, we recruited 180 healthy children, aged 13-14 years in two groups and supplemented Group A (60 children) with 60,000 IU of fat-soluble vitamin D3/month with milk and Group B (120 children) with 60,000 IU/month of water miscible vitamin D3 under supervision for 6 months. Serum 25(OD)D, parathyroid hormone (PTH), calcium, phosphate, and alkaline phosphatase (ALP) levels were evaluated before and after supplementation in 156 children (54 in Group A and 102 in Group B) who completed the study. RESULTS: We observed a significantly greater increase in the serum 25(OH)D levels in group B as compared to group A (31.8±9.1 ng/mL vs. 23.7±10.4 ng/mL; p<0.001). All children in group B achieved adequate levels of serum 25(OH)D (>20 ng/mL) as against 83.3% children in group A. Serum PTH and ALP levels declined considerably in both the groups following supplementation. CONCLUSIONS: Vitamin D supplementation significantly increased the serum 25(OH)D levels in both groups. Miscible form of vitamin D3 appears to be better in achieving higher levels of serum 25(OH)D than that observed with a similar dose of fat-soluble vitamin D3. Further studies with different dose regimens are required to establish its efficacy over the conventionally used fat-soluble vitamin D3.

Vitamin D: A New Promising Therapy for Congenital Ichthyosis.

Severe vitamin D deficiency and rickets are highly prevalent among children with congenital ichthyosis. We report an incidental observation of a dramatic and excellent clinical response with regard to skin scaling and stiffness in children with congenital ichthyosis after short-term high-dose vitamin D supplementation that has not been previously described. Seven children with congenital ichthyosis (5 with autosomal recessive congenital ichthyosis; 2 with epidermolytic ichthyosis) and severe vitamin D deficiency (and/or rickets) were given 60,000 IU of oral cholecalciferol daily for 10 days under supervision. All children were subsequently put on recommended daily allowance of 400 to 600 IU of cholecalciferol. The main outcome measures observed and studied were reduction in skin scaling and stiffness of the extremities. All cases had severe vitamin D deficiency (serum 25-hydroxyvitamin D < 4 ng/mL) and secondary hyperparathyroidism. Six patients had clinical and radiologic evidence of rickets. Significant improvement in scaling was noticeable by day 5, showing further improvement by day 10, in 6 of the 7 cases. At 1 month, the skin had become near normal in all the cases of autosomal recessive congenital ichthyosis. Remarkable reduction in stiffness was also observed in all children. Supplementation with high-dose vitamin D followed by recommended daily allowance appears to be an effective form of therapy in the management of congenital ichthyosis with vitamin D deficiency.

Management of infantile hemangiomas: current trends.

Infantile hemangiomas (IH) are common vascular tumours. IH have a characteristic natural course. They proliferate rapidly during the early infantile period followed by a period of gradual regression over several years. Most of the uncomplicated IH undergo spontaneous involution, with a small proportion of cases requiring intervention. These are children with IH in life-threatening locations, local complications like haemorrhage, ulceration and necrosis and functional or cosmetic disfigurements. Systemic corticosteroids have been the first line of treatment for many years. Recently, non-selective beta-blockers, such as oral propranalol and topical timolol, have emerged as promising and safer therapies. Other treatment options include interferon α and vincristine which are reserved for life-threatening haemangiomas that are unresponsive to conventional therapy. This review mainly focuses on the current trends and evidence-based approach in the management of IH.