Erythrokeratoderma variabilis

Introduction

Erythrokeratodermias (EK) are a heterogenous group of inherited cornification disorders.[1] EK were classified as i) confluent and reticular EK of Gougerot and Carteaud, ii) variable EK of Mendes da Costa and iii) symmetric progressive EK.[2] Erythrokeratoderma variabilis (EKV) is a rare, ichthyosiform disorder, first, described by Mendes da Costa in 1925.[3] Clinically, the lesions, which are of two types, usually appear in the early months of life but may occasionally develop considerably later.[4] There are dark, erythematous, well-demarcated plaques, symmetrically arrayed, relatively fixed in site,[5] showing a predilication for the extensor surfaces. There are also transient lesions consisting of distinctive polycyclic or comma-shaped erythematous macules, occurring at any site, which last days or weeks and may either fade in situ or migrate slowly over the surface followed by fine scale.[6] Additionally, hypertrichosis of vellus hair and mild keratoderma of palms and soles may be present.[7] Histopathological studies show that the lower most portion of the stratum corneum is compact while the majority of the stratum corneum exhibits a loose basket-weave pattern. Other features are papillomatosis, hyperplasia of ridges and a perivascular lymphohistiocytic infiltrate in the papillary dermis.[8] However, the ultrastructural finding of subnormal numbers of epidermal keratinosomes within hyperkeratotic plaques is characteristic of this disorder.9

Case Report

A 30 year old male had reddish-brown plaques since the last 25 years. The plaques were thickened, brown, pigmented and sharply delineated. Also noted at that time were asymptomatic islands of configurate erythema on the trunk and extremities which varied in size, position, shape and number. On examination, well-defined, reddish-brown, hyperkeratotic, bilaterally symmetrical plaques were present over the elbows, knees and ankles. These lesions showed accentuation of skin creases and have been fixed in their site since onset. This was accompanied by transient, erythematous lesions consisting of discrete, amoeboid margined, finely scaly erythematosus patches of variable size, with bizarre geographical configuration, distributed irregularly over the upper and lower extremities, front and back of trunk with relative sparing of face. These lesion were mildly itchy, migratory in nature, lasting days or weeks and subsequently either fading with yellowish-brown scaling or involuting completely and appearing at new sites, thereafter. There was no history of exacerbation of these lesions following exposure to cold, heat, wind or emotional upset. The patient′s general health was good and he was not receiving any medication. The palms and soles exhibited a mild, diffuse keratoderma. Family history did not reveal any evidence of this disorder. The nails, teeth and mucous membranes appeared normal. The remainder of the physical examination revealed no abnormalities. Complete and differential blood cell counts, liver function tests and urinary analysis gave results within normal limits.

Discussion

EKV is a very rare type of EK, determined by a autosomal dominant gene of variable expressivity, characterized by reddish-brown plaques, which are hyperkeratotic and fixed in location, particularly, over the knees, elbows and ankles and figurate patches of erythema which vary in size, shape and location and that move around. In our patient, family history was negative, onset was around the age of 5 years and in addition to the typical plaques and migratory, circinate patches; mild diffuse palmoplantar keratoderma was present.