A 7-year-old girl with presumed atopic dermatitis was evaluated at our institution’s department of dermatology. She had a history of erythroderma at birth and later showed signs of delayed growth. During her first years of life, she developed multiple food allergies, allergic asthma, and rhinitis. Her skin was dry, with marked redness of her face and hands (Figure 1A). Because of her sparse and brittle hair and thin eyebrows, Netherton syndrome (NS) was suspected. Examination of her hair using light microscopy showed invagination of the hair at several points along the shaft, which was consistent with trichorrhexis invaginata (“bamboo hair”) (Figure 1B). Immunohistochemistry performed on a skin biopsy showed absent staining for lymphoepithelial Kazal-type-related inhibitor. The diagnosis was confirmed by molecular genetic analysis, which showed 2 heterozygous pathogenic variants in the SPINK5 gene.