Successful dupilumab treatment of an adult with Netherton syndrome.

Netherton syndrome (NS), ichthyosis linearis circumflexa, is a rare autosomal recessive disorder. NS is caused by pathogenic loss-of-function variants in the serine protease inhibitor of Kazal type 5 gene (SPINK5), compromising lymphoepithelial Kazal type 1 inhibitor (LEKTI-1) function. The unopposed serine protease activity due to reduced LEKTI-1 inhibition in NS leads to premature degradation of corneodesmosomes, causing decreased stratum corneum cohesion and thinning.