Epidermolysis Bullosa Simplex Caused by Distal Truncation of BPAG1-e: An Intermediate Generalized Phenotype with Prurigo Papules

The study described a case of epidermolysis bullosa simplex (EBS) in a 39-year-old Syrian man, caused by a rare homozygous nonsense mutation in the DST gene, leading to a truncated BPAG1-e protein. This mutation resulted in an intermediate generalized phenotype with skin fragility, blistering, and prurigo papules, but did not affect hair, nails, or mucous membranes. Immunofluorescence and immunoblot analyses showed reduced expression and truncation of BPAG1-e, impairing its binding to intermediate filaments. The mutation might have led to increased expression of plectin and contributed to pruritus through up-regulation of proinflammatory cytokines. This case highlighted a novel phenotype linked to DST mutations, underscoring BPAG1-e's role in skin integrity and pruritus.