Epidermolysis bullosa simplex

Epidermolysis bullosa simplex (EBS) is a disorder resulting from mutations in the genes encoding keratin 5 or keratin 14.

Blister formation of EBS is within the basal keratinocyte of the epidermis. Sometimes EBS is called epidermolytic.

Subtypes
There are four subtypes of EBS:


 * 1) EBS - Weber-Cockayne (EBS-WC)
 * 2) EBS - Koebner (EBS-K)
 * 3) EBS - Meara (EBS-DM)
 * 4) EBS - Mottled pigmentation (EBS-MP)

Weber-Cockayne
Weber-Cockayne is the mildest form of EBS, leading to blistering of the hands and feet since these are most susceptible to frequent abrasion. The presence of heat and humidity, either through climate or physical activity, accelerates the formation of blisters. Typically, the blisters formed are tense and painful, and make walking difficult. Carefully lancing, draining and bandaging the blisters can provide relief and prevent them from expanding.

Koebner
Koebner results in generalised blisters.

Dowling-Meara
Dowling-Meara (EBS-DM) is the most severe form of EBS, leading to clusteres of blisters and spherical keratin aggregates. It results from a missense mutation in KRT5 (E477K) or one of two missense mutations in KRT14 (R125C and R125H)

Mottled pigmentation
Mottled pigmentation (EBS-MP) is caused by one missense mutation in KRT5 (I161S) or by missense mutations in the plectin gene.