Autosomal recessive inheritance of erythrokeratoderma variabilis

А case of erythrokeratodermia variabilis (Mendes da Costa type) in a three-year-old child

The authors describe a case of erythrokeratodermia variabilis (Mendes da Costa type) in a three-year-old child. They present data on the clinical picture and histological examination. Major stages of the etiology and pathogenesis of the diseases are described.

Erythrokeratodermas: A classification in a state of flux?

The term 'erythrokeratodermas' or 'erythrokeratodermias' has been applied to a group of inherited disorders characterized by well-demarcated erythematous lesions and hyperkeratotic plaques. Connexin mutations have been demonstrated to be responsible for most cases of erythrokeratoderma variabilis but there remain some cases without demonstrated connexin mutations, suggesting genetic heterogeneity. The position of progressive symmetric erythrokeratoderma has become rather unclear. Loricin mutations have been found in some cases that clinically resemble variant Vohwinkel syndrome and other cases have features that overlap with those of erythrokeratoderma variablis. Whether progressive symmetric erythrokeratoderma exists as a distinct entity is under question.

Case study: erythrokeratodermia variabilis

A 4-year-old girl presented to the dermatology clinic with complaints of erythematous skin lesions on her face, extremities,forearms, and joints. The patient was a product of a full-term, normal pregnancy and delivery and was born to healthy parents. The parents are cousins. The condition started a few months after birth with small, hyperkeratotic patches on her cheeks. These lesions did not respond to the treatment that was given. The condition progressed and a few months later similar skin lesions started to appear on her forearms and knees. Different types of treatment, such as topical antibiotics,emollients, topical steroids, and systemic antihistamines, have been tried without any benefit. Some lesions showed variable exacerbations and remissions. There was no family history of a similar problem, although her older brother showed marginal hair loss without any skin lesions. On physical examination (Figures 1-3), hyperkeratotic erythrodermic plaques of variable thickness with sharply demarcated borders were seen on cheeks, extensor surfaces of forearms, and on the knees. The palms,soles, nails, and teeth were normal. The hair showed normal appearance, but there was no hair growth on the margins of the scalp. The laboratory investigations showed normal complete blood count and normal serum zinc and ferritin levels. Urine microscopy and examination was normal. Skin biopsy was taken and histopathology showed nonspecific features of hyperkeratosis with moderate papillomatosis and acanthosis (Figure 4). A diagnosis of erythrokeratodermia variabilis was made and the patient was started on emollients as treatment. There was not much improvement with the treatment.

Recent advances in the molecular basis of inherited skin diseases

Over the last few years the molecular basis of several inherited skin diseases has been delineated. Some discoveries have stemmed from a candidate gene approach using clinical, biochemical, immunohistochemical, and ultrastructural clues, while others have arisen from genetic linkage and positional cloning analyses. Notable advances have included elucidation of specific gene pathology in the major forms of inherited skin fragility, ichthyosis, and keratoderma. These findings have led to a better understanding of the significance of individual structural proteins and regulatory enzymes in keratinocyte adhesion and differentiation. From a clinical perspective, the advances have led to better genetic counseling in many disorders, the development of DNA-based prenatal diagnosis, and a foundation for planning newer forms of treatment, including somatic gene therapy, in selected conditions.