An 18-month-old boy presented with persistently scaly, dry skin since birth. At birth, the patient presented with widespread erythroderma and erosions. The family was advised to apply daily emollients. Upon presentation to our clinic, the child was afebrile and with no evidence of acute distress. Dermatological examination revealed mild erythroderma and diffuse white to grey scaling with hyperkeratosis, most prominent on the extensor surfaces of the extremities and the scalp (Figure 1). The palms and soles were not involved, and no ectropion was seen. There were no blisters, mucosal surfaces were intact, and both scalp hair and nails appeared normal. There were no parental consanguinity and no family history of skin disorders. A skin biopsy was recommended, but the family declined. Gene testing was carried out. Autosomal dominant epidermolytic ichthyosis (EI). Whole Exome Sequencing (WES) was performed using the Agilent SureSelect kit and Illumina HiSeq. 2500 system, followed by GATK variant calling and in-house annotation. A heterozygous pathogenic variant in KRT10 (NM_000421.5:c.467 G > A, p.(Arg156His)) was identified in the proband. The family was informed of the updated diagnosis and counselled on appropriate management. They were advised to bathe the child using a gentle, soap-free cleanser and to apply a thick layer of emollient twice daily. For areas of erythroderma, a short 2-week course of betamethasone dipropionate 0.05% cream once daily was prescribed, to be applied only to erythematous areas. At follow-up 2 months later, a dramatic improvement in both the erythroderma and scaling was observed. EI, previously known as epidermolytic hyperkeratosis and bullous congenital ichthyosiform erythroderma, is a rare, autosomal dominant genodermatosis, affecting 1 in over 200,000 newborns, with 50% are spontaneous mutations [1]. The disease results from pathogenic variants in the genes encoding the suprabasal keratins 1 (KRT1) and 10 (KRT10), which disrupt the formation of keratin intermediate filaments within suprabasal keratinocytes [2]. In the present case, the detected KRT10 variant (NM_000421.5:c.467 G > A, p.(Arg156His)) has been previously reported in affected individuals, thereby confirming its pathogenicity and its association with the classical clinical course of EI, characterized by early-life blistering followed by progressive hyperkeratosis [3, 4]. Variants involving KRT1 are typically associated with palmoplantar involvement, reflecting the broader expression of this keratin in acral sites, whereas KRT10 demonstrates limited expression in these regions [2, 3]. This molecular variation aligns with our patient's lack of palmoplantar manifestations. At birth, EI manifests with erythema, blisters, and superficial erosions, mostly involving the flexural regions. Blister formation is precipitated by minor trauma, friction and secondary infection. As the child grows, blister formation typically diminishes and is gradually replaced by epidermal thickening and scaling after the initial months of life [5]. The differential diagnosis in our patient at birth includes EI, epidermolysis bullosa, and staphylococcal scalded skin syndrome, given the presence of erythroderma and blistering. However, with advancing age, blistering resolved, and hyperkeratosis, mainly involving the flexural areas, became the predominant feature. This clinical evolution favoured a diagnosis of EI, which was subsequently confirmed by genetic testing [5, 6]. There is no curative treatment for EI and management of is mainly supportive. Gentle daily bathing combined with twice-daily application of emollients is considered fundamental. Alpha-hydroxy acids help regulate keratinization and enhance skin appearance with regular use. Scalp involvement may be treated through frequent shampooing and gentle removal of scales. In more severe cases, acitretin at a dosage of 0.5–1.0 mg/kg body weight has shown effectiveness in minimizing hyperkeratosis. However, systemic retinoids, while promoting desquamation, must be used cautiously due to their potential to worsen blistering [2-7]. This case highlights the importance of considering EI in the differential diagnosis of neonatal blistering disorders and emphasizes the role of genetic testing in establishing an accurate diagnosis and guiding long-term management. Early differentiation between EI and EB not only prevents unnecessary interventions but helps implement accurate long-term management strategies. Hamad El Hajj: writing, drafting, editing, diagnosis, management. Dima Jeha: writing, conceptualization. Andre Megarbane: writing, drafting, editing; supervision. Hala Megarbane: investigation, writing, validation, supervision. The parents of the patient have given written informed consent for their child's participation in the study, as well as for the use of their child's deidentified, anonymized, aggregated data, and case details (including photographs) for publication. Ethical approval: not applicable. The authors declare no conflicts of interest. The data that support the findings of this study are available from the corresponding author upon reasonable request.
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