The ichthyoses encompass a heterogeneous group of genetic disorders identified by varying degrees of erythema, scale, hyperkeratosis, xerosis, and pruritus. Non-syndromic and syndromic forms of ichthyoses exist, but common among all inherited ichthyoses is alteration in keratin maturation and function. A 28-year-old African-American woman was referred to dermatology for a rash. Punch biopsy revealed psoriasiform epidermal change and epidermolytic hyperkeratosis. The patient was diagnosed with epidermolytic ichthyosis (EI) and started on cyclosporine, methotrexate, and later ustekinumab with symptom control. The patient’s family history was remarkable for similar skin findings. A cross-sectional study to build a familial tree of the disease was performed. Detailed information required to build the tree was obtained by telephone interview, and disease phenotype was characterized using the Visual Index for Ichthyosis Severity for scale and erythema (VIIS). Evaluation of eight individuals from three generations of the same family revealed (1) X-linked recessive Mendelian genetics, (2) VIIS (M=5.6; SD=2.1), (3) VIIS standard four body sites: upper back (M=0.25; SD=0.46), upper arm (M=1.4; SD=1.2), lower leg (M=1.7; SD=1.0), and dorsal foot (M=1.6, SD=0.74), (4) additional body sites, not included in total severity score: lower back (M=1.4; SD=0.74), abdomen (M=1.3; SD=0.45), and anterior ankle (M=2.5; SD=0.85), (5) scale body surface area (BSA) (M=30.0; SD=10.1), (6) erythema BSA (M=5.2; SD=5.2), and (7) age of onset (M=15.75 months; SD=19). The primary conclusion suggests a novel genetic mutation for EI demonstrating an X-linked recessive mode of inheritance and earlier age of disease onset in each successive generation.

ESDR086 - Familial Tree of Epidermolytic Ichthyosis Suggesting a Novel Genetic Mutation

50th Annual Meeting of the European Society for Dermatological Research. VIRTUAL MEETING