A case of erythrokeratoderma variabilis without mutations in connexin 31

Abstract

Erythrokeratoderma (EK) variabilis is a heterogeneous group of diseases characterized by migratory erythematous patches and hyperkeratotic plaques. Mutations in connexin 31 have recently been found to underlie several cases of EK variabilis. We describe a Japanese girl with extensive lesions that appeared to be a form of EK variabilis, clinically resembling genodermatose en cocardes (Degos). Our patient had characteristic migratory rosette or target‐like erythematous keratotic plaques with peripheral scaling in addition to relatively fixed keratotic plaques. Sequencing of the connexin 31 gene did not detect mutations. Skin biopsy showed parakeratotic hyperkeratosis with hypergranulosis. Immunohistochemically, suprabasal keratins, involucrin and profilaggrin were unequivocally expressed, while loricrin expression was greatly diminished and deiminated K1 was undetectable. Our results confirm aetiological heterogeneity in EK. The histological features suggest disruption of keratinocyte terminal differentiation at a very late stage.

Erythrokeratodermia variabilis: Two case reports

“…These subtypes are independent, and their shapes and distribution can be changeable at any time. [25] The lesions have propensity to locate on the distal extremities, buttocks, and trunk. Hyperkeratotic plaques are particularly distributed on the face, hip, and extensor aspect of the limb.…”

“…[25] Connexins come together to form hexameric aqueous channels or connexons in the cell membrane. [4] However, connexin mutation was not detected in some EKV cases.…”

Erythrokeratoderma variabilis without GJB3 or GJB4 mutation: a review of Japanese patients

“…In Table 1, we summarize the data of four Japanese patients with EKV who were investigated genetically 8–10 . These suggest several specific features for Japanese patients with EKV: (i) all four patients were female; (ii) no patient had a positive family history; and (iii) no patient had mutations in GJB3 or GJB4 .…”

Gap Junctions in Development and Disease

“…Subsequently, several new missense mutations of GJB3 (Wilgoss et al 1999;Richard et al 2000) and pathogenic mutations in the neighboring connexin gene GJB4 encoding Cx30.3 were identified (Macari et al 2000;Richard et al 2003). Despite these findings, a small number of EKV patients do not harbor pathogenic connexin gene mutations and the molecular basis of the disorder in these patients still remains elusive (Ishida-Yamamoto et al 2000;Arita et al 2003;Richard et al 2003). Both Cx31 and Cx30.3 belong to the group of β-type connexins and are preferentially expressed in the upper, differentiated keratinocytes of human epidermis, suggesting they play a crucial role during epidermal differentiation (Macari et al 2000;Richard et al 2003).…”