A newborn girl with harlequin ichthyosis genetically confirmed by ABCA12 analysis

Harlequin ichthyosis (HI, OMIM #242500) is one of the most severe skin diseases among the autosomal recessive congenital ichthyoses, with high morbidity and mortality, particularly in newborns. Clinically, it is characterized by a typical appearance of generalized, thick, yellowish, hyperkeratotic plates with deep erythematous fissures on the skin. Herein, we present the case of a newborn girl with HI that was genetically confirmed by targeted gene panel analysis. The premature baby was encased in an opaque white membrane with erosion covering the skin of the entire body except the lips, with her hands and feet restricted by the membrane. Humidification, emollient, and retinoic acid treatment were started; the thick ichthyosis gradually peeled off and the underlying skin was only covered with thin scales. Targeted gene panel analysis using next-generation sequencing and validation with Sanger sequencing and quantitative polymerase chain reaction analyses confirmed compound heterozygous mutations of the ABCA12 gene (p.N1380S and a partial gene deletion encompassing exon 9). The parents were carriers for each of the identified mutations. Early recognition of the genetic etiology of congenital ichthyosis can, thus, facilitate genetic counseling for patients and their families.