No abstract

Background-Anti-epiligrin cicatricial pemphigoid (AECP) is a mucosal predominant subepidermal blistering disease associated with an increased relative risk of cancer. In contrast to prior reports showing that anti-L-332 autoantibodies are a reliable marker for patients with AECP, a recent report suggested that as many as 40% of patients with bullous pemphigoid (BP) have IgG reactive with this laminin isoform.

Non-Herlitz junctional epidermolysis bullosa (nH-JEB) is caused predominantly by mutations leading to premature stop codons on both alleles of the type XVII collagen gene (COL17A1). The analysis of mutations in this gene has provided a means of correlating genotype with phenotype of nH-JEB patients. The phenotype of nH-JEB is characterized by generalized blistering of skin and mucous membranes with atrophic scarring and nail dystrophy. Atrophic alopecia is a distinct feature of nH-JEB patients, but one that is not associated with the severity of the disease at other sites. Enamel hypoplasia and pitting of the teeth are also characteristic for nH-JEB and can be used to facilitate the correct diagnosis in children with a blistering skin disease. Analysis of the biological consequences of mutations in the COL17A1 gene has shown that most patients lack type XVII collagen mRNA due to nonsense-mediated mRNA decay. Patients with these mutations can therefore be a target for corrective gene therapy using vectors coding for full-length type XVII collagen. Proof of principle for this approach has recently been demonstrated. The analysis of naturally occurring phenomena of gene correction in the COL17A1 gene provides evidence for other mechanisms of gene correction in genetic diseases. For example, exclusion of an exon carrying a mutation can lead to a milder phenotype of nH-JEB than predicted by the original mutation. In addition, we have gained data suggesting that COL17A1 exons harbouring pathogenic mutations can also be repaired by trans-splicing, i.e. aligning corrected RNA sequences to introns in the vicinity of faulty exons in the COL17A1 premtRNA.

Genetic syndromes including basal cell nevus syndrome (BSNS), xeroderma pigmentosum (XP), and epidermodysplasia verruciformis (EV) predispose the individual to skin cancer. Basal cell carcinomas (BCCs) often develop in patients with BCNS and XP. One of the aims of surveillance examination in these patients is to detect BCC while the tumors are still small and easy to manage. Dermoscopy, by allowing the visualization of arborizing vessels, ovoid nests, nonaggregated blue-gray globules, and spoke-wheel and leaf-like structures, can facilitate in the early detection of BCC. Patients with XP are also at risk for developing squamous cell carcinoma (SCC). Dermoscopy can assist in the early detection of these cancers by allowing the observer to visualize focal glomerular vessels, which is a common feature seen in SCC. This feature can also assist in detecting SCC developing in other syndromes such as EV and epidermolysis bullosa (EB). In addition to helping in the detection of BCC and SCC, dermoscopy can also help detect melanoma in individuals with XP and evaluate nevi developing in those with EB. This review will discuss how dermoscopy can be used in the management of patients with BSNS, XP, EV, and EB and will discuss the dermoscopic findings of vascular lesions, including pyogenic granuloma, hemangioma, port-wine stain, and lymphangioma circumscriptum.

Recurring dermoscopic structures in EB naevi reveal a distinctive dermoscopic pattern of this recently defined entity. Although EB naevi represent an exception to dermoscopic diagnostic algorithms, their dermoscopic evaluation most often allows us to estimate their benign nature. Nevertheless, as an unequivocal discrimination from malignant melanoma in vivo is sometimes not possible, regular clinical follow up of EB naevi with histopathological evaluation of highly suspicious lesions is mandatory.