Secukinumab as a Novel Treatment for Chronic Netherton Syndrome in a Young Adult

BACKGROUND Netherton syndrome is an autosomal recessive skin disorder usually diagnosed in infancy and is characterized by ichthyosis, erythroderma, atopy, and characteristic beading of the hair shaft (trichorrhexis invaginata). Secukinumab, a monoclonal antibody that inhibits interleukin-17, has recently been reported to be effective in patients with refractory Netherton syndrome. The present report describes a 20-year-old man with a chronic history of refractory Netherton syndrome who responded to treatment with secukinumab. CASE REPORT A 20-year-old male patient presented with generalized pruritus, erythema, and scaling. The patient was previously diagnosed with atopic dermatitis and had been treated with systemic corticosteroids and omalizumab, without improvement. Later, the patient was referred to us. Physical examination showed generalized erythroderma and polycyclic and serpiginous erythematous plaques with double-edged scales at the margins. Trichoscopy of the scalp revealed a hair shaft abnormality, specifically trichorrhexis invaginata. The blood tests demonstrated elevated IgE levels. Initially, the patient was started on topical corticosteroids, which caused the condition to deteriorate. As the patient did not respond to the treatment, a decision was made to start secukinumab monotherapy. After 2 injections, the patient's condition markedly improved and the effect after the last injection was maintained for 4-5 months. CONCLUSIONS Netherton syndrome is a rare and often misdiagnosed hereditary diseases in dermatology. For this reason, the management strategies of the disease are variable and without consensus. In our case, considering the pathogenesis of the disease, we used secukinumab, which has shown promising results and good tolerability. Further studies are required to establish the efficacy of the drug.