Epidermolysis bullosa pruriginosa: a case with a novel mutation and co-existent lichen amyloidosus.

Epidermolysis bullosa pruriginosa is a rare variant of dystrophic epidermolysis bullosa characterized by severely pruritic and cicatricial lesions localized to the extensor extremities. We report a Singaporean Chinese male with epidermolysis bullosa pruriginosa with an underlying novel mutation in the COL7A1 gene. A heterozygous acceptor splice site mutation IVS67-1G>T probably led to in-frame skipping of exon 68 (36-basepairs), resulting in a loss of 12 amino acids. Among his three children, only the youngest son, who had bilateral big toenail thickening, possessed the same mutation. His skin biopsy one decade ago revealed association of focal amyloidosis; a recent skin biopsy showed more established features of lichen amyloidosis. It is debatable whether the cutaneous amyloidosis was a secondary or primary phenomenon. Our report highlights that the diagnosis of epidermolysis bullosa pruriginosa may be obscured when cutaneous amyloidosis is coexistent.

Epidermolysis bullosa pruriginosa: a rare presentation with asymptomatic lesions.

Epidermolysis bullosa pruriginosa (EBP) is a subtype of dominant dystrophic epidermolysis bullosa (DDEB) and is clinically characterized by pruritic lichenified plaques or prurigo-like lesions with violaceous linear scarring. Pruritus has always been described as one of the most striking features in EBP. Mutations in COL7A gene, especially in the glycine residue, have been shown to cause this form of DDEB. In this report, we describe a north Indian familial clustering of three cases of EBP, spread across two generations, presenting with hypertrophic lichenoid cutaneous lesions, which were completely asymptomatic. Clinical and histopathological analysis favored the diagnosis of EBP in all three cases. They are being reported for their unusual asymptomatic presentation.

Immunofluorescence antigen mapping for hereditary epidermolysis bullosa.

Epidermolysis bullosa (EB) is a group of inherited, mechanobullous disorders that are caused by mutations in the structural proteins in the epidermis or dermoepidermal junction. Characteristic clinical picture is the presence of blisters at trauma prone areas of the body, which develops at or soon after birth. Availability of specific monoclonal antibodies against the target proteins together with advances in the molecular genetics have led to the revision in the classification of EB. Now four major types of EB are recognized depending upon the level of blister and the location of target protein: EB simplex (epidermolytic), junctional EB (lucidolytic), dystrophic EB (dermolytic) and Kindler's syndrome (mixed cleavage plane). The laboratory tests not only help to confirm the diagnosis of EB but are also an important tool to classify (and subtype) EB. These include immunofluorescence antigen mapping (IFM), transmission electron microscopy (TEM) and mutation analysis. IFM is the most preferred method for final diagnosis of EB worldwide. It is relatively easy to perform and results can be obtained rapidly. This article describes the technicalities and significance of IFM in various types of EB.