Topical pimecrolimus: a novel therapeutic option for Netherton syndrome

Conflict of interest: none declared. Sir, Netherton syndrome (NS) is an autosomal recessive ichthyosis characterized by the triad of congenital ichthyosiform erythroderma (CIE) or ichthyosis linearis circumflexa (ILC), trichorrhexis invaginata or other hair shaft anomalies, and severe atopic diathesis.1 Its incidence has been estimated at one in 200 000;2 none the less, NS may account for up to 18% of all cases of infantile erythroderma.3 It also features associated symptoms such as neonatal dehydration, failure to thrive and recurrent infections. The disease is caused by mutations in the SPINK5 gene resulting in a lack of the serine protease inhibitor LEKTI and a dysregulation of epidermal proteolysis.4, 5 So far, no effective therapy is available. Chronic inflammation of the skin is a major clinical problem and thus NS is an excellent target for treatment approaches using topical immunomodulators. In the past, patients with NS have been treated successfully with tacrolimus,6 but significant absorption due to the impaired epidermal barrier prevents widespread application of this drug in NS.7 We describe a boy with NS who was successfully treated with pimecrolimus cream 1% without serious side‐effects and without developing significant systemic absorption of pimecrolimus over a period of 3 months.