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.