Epidermolytic hyperkeratosis: clinical update

Clinical and genetic findings in 13 Chinese children with keratinopathic ichthyosis

Importance

Keratinopathic ichthyosis (KPI) represents a group of predominantly autosomal dominant genodermatoses resulting from mutations in the KRT1, KRT2, or KRT10 genes. In KPI, the relationship between genotype and phenotype is complex.

Objective

To analyze the clinical manifestations and gene mutations in Chinese patients with KPI.

Methods

Clinical data were collected from 13 children diagnosed with KPI, and peripheral blood DNA samples were extracted from both the patients and their parents Next-generation sequencing was performed using a congenital ichthyosis multi-gene panel, and the selected variants in the patients and their parents were further validated using the Sanger sequencing method.

Results

Genetic analysis identified missense mutations in either KRT1 or KRT10 in ten patients exhibiting varying degrees of severity and distinct features of epidermolytic ichthyosis. A missense hotspot mutation in KRT2 was identified in one patient with superficial epidermolytic ichthyosis. Additionally, two truncation mutations in KRT10 were detected, leading to the development of generalized ichthyosiform erythroderma. Ear malformation and ectropion at birth, scalp involvement, and palmoplantar hyperkeratosis were observed as early signs of ichthyosis with confetti.

Interpretation

We analyzed the genotype-phenotype correlations in KPI, revealing that the types and locations of different mutations are associated with distinct phenotypic characteristics. Oral acitretin could be considered a treatment option for severe patients at an appropriate dosage and timing.

Staphylococcus aureus bacteremia and infective endocarditis in a patient with epidermolytic hyperkeratosis: A case report

BACKGROUND

Staphylococcus aureus bacteraemia (SAB) is among the leading causes of bacteraemia and infectious endocarditis. The frequency of infectious endocarditis (IE) among SAB patients ranges from 5% to 10%-12%. In adults, the characteristics of epidermolytic hyperkeratosis (EHK) include hyperkeratosis, erosions, and blisters. Patients with inflammatory skin diseases and some diseases involving the epidermis tend to exhibit a disturbed skin barrier and tend to have poor cell-mediated immunity.

CASE SUMMARY

We describe a case of SAB and infective endocarditis in a 43-year-old male who presented with fever of unknown origin and skin diseases. After genetic tests, the skin disease was diagnosed as EHK.

CONCLUSION

A breached skin barrier secondary to EHK, coupled with inadequate sanitation, likely provided the opportunity for bacterial seeding, leading to IE and deep-seated abscess or organ abscess. EHK may be associated with skin infection and multiple risk factors for extracutaneous infections. Patients with EHK should be treated early to minimize their consequences. If patients with EHK present with prolonged fever of unknown origin, IE and organ abscesses should be ruled out, including metastatic spreads.

Treatments for Non-Syndromic Inherited Ichthyosis, Including Emergent Pathogenesis-Related Therapy

The term 'inherited ichthyosis' refers to a heterogeneous group of mendelian disorders of cornification that involve the integument with varying degrees of scaling. The management of ichthyosis poses a challenge for most physicians. Treatment options proposed in the literature include moisturizers, topical keratolytics, topical and systemic vitamin D analogues, and topical and systemic retinoids; however, some of these modalities are less reliable than others. Despite the therapeutic impasse imposed by the options above, the emergence of pathogenesis-based treatments along with novel gene therapies appear promising and hold the potential to halt or even revert disorders that arise from single genetic mutations, although research is still quite lacking in this domain. Hence, this review aims to highlight the various treatment modalities available for the management of the cutaneous manifestations of non-syndromic inherited ichthyosis, with an added emphasis on pathogenesis-targeted therapies.

Epidermolytic Hyperkeratosis in an Epidermoid (Infundibular) Cyst

ABSTRACT

Epidermolytic hyperkeratosis (EHK) is an uncommon histopathologic reaction pattern that may represent a primary pathological process or a coincidental finding in a variety of neoplasms. We present a case of EHK in an epidermoid (infundibular) cyst. Histopathologically, EHK demonstrates vacuolar degeneration of keratinocytes in the spinous and granular cell layers, with disrupted cellular boundaries, enlarged basophilic keratohyalin-like granules and amorphous eosinophilic inclusions, along with massive hyperkeratosis. In addition to the morphologic description of EHK, we summarize the diagnoses in which EHK has been reported. Prior cases of EHK in an epidermoid (infundibular) cyst are summarized to compare findings. The significance of incidental EHK in skin lesions is unknown.

A novel KRT1 c.1433A>G p.(Glu478Gly) mutation in a newborn with epidermolytic ichthyosis

Epidermolytic Ichthyosis is a rare genodermatosis related to point mutations affecting the genes encoding for keratin 1 or keratin 10. We report a case of Epidermolytic Ichthyosis in a newborn with a novel mutation (c.1433A>G) of KRT1 gene.