Epidermolysis bullosa Simplex-Dowling–Meara mimicking epidermolysis bullosa simplex with mottled pigmentation

Abstract

Epidermolysis bullosa simplex-Dowling–Meara (EBS-DM) variant is an autosomal dominant blistering genodermatosis due to mutations in genes coding for keratin 5 (K5) or keratin 14 (K14), specifically at the rod domain. Postinflammatory dyspigmentation can arise at sites of blistering, sometimes in a reticulate or mottled configuration. This mimics EBS with mottled pigmentation (EBS-MP), usually due to mutation in the head domain of K5, for which the pigmentation is not preceded by blisters. We report a case of an adult Malay male with recurrent blisters and mottled hyperpigmentation over his trunk and limbs, consistent with EBS-DM clinically, and confirmed on genetic mutation sequencing. Different K5 or K14 mutations, by altering keratinocyte adhesion and interfering with melanin pigment transport, can lead to variable phenotypes of skin fragility and/or hyperpigmentation, possibly modulated by other genetic or environmental factors.