X-linked Ichthyosis Presenting as Erythroderma: A Rare Case.

X-linked ichthyosis is a rare form of dermatological disease and when it presents as erythroderma it is even rarer. History of consanguineous marriage and prolonged labor during birth of patient, generalized scaling which gets better in summer months, flexural involvement, cryptorchidism made a diagnosis of X-linked ichthyosis. We report this case because of its rarity as erythroderma.

What was known?

In childhood erythroderma ichthyosis is one of the causes and among the ichthyoses lamellar ichthyosis and non-bullous ichthyosiform erythroderma are the common causes of erythroderma followed by ichthyosis vulgaris and others.

Introduction

X-linked ichthyosis is considered one of the five main types of ichthyosis. The others are ichthyosis vulgaris, lamellar ichthyosis, congenital non-bullous ichthyosiform erythroderma and epidermolytic hyperkeratosis. X-linked ichthyosis is less common in occurrence (1 in 2000 births)[12] and it is rarer in presentation as erythroderma.[3]

We reported this case because of its rarity as erythroderma.

Case Report

A one-and-half year old boy presented with generalized scaling over whole body and redness over both cheeks. There was a history of consanguineous marriage and prolonged labor and baby was delivered by normal vaginal delivery. The birth weight of the baby was 2.3 kg and the length of the baby was 36 cm. There was no history suggestive of collodion membrane. Scaling started from 3 weeks of age and had a history of exacerbation in the winter and improvement in summer. Immunization was completed according to the immunization schedule. There was no family history of similar kind of illness. There was no history of any drug intake prior to the scaling or atopic diathesis. On examination there was fine white to brown scaling over the whole body without any spared area with glistening surface over palms and soles with involvement of flexures. On the scalp fine whitish-grey and grayish brown scaling was present and in some areas there was thick crusting which on removal revealed a moistened surface. On the frontal scalp margin, there were large grayish-brown ichthyotic scales. Both the cheeks were erythematous along with scaling [Figures 1 and 2] and scales also involved the upper eyelid, upper lips and over the nose. There was no abnormality in the eyes except mild ectropion. There was no evidence of seborrheic blepharitis. Left-sided cryptorchidism was present [Figure 3] for which the patient was referred to pediatric surgery and they have suggested waiting for another 6 months after which they would suggest surgical intervention. Ophthalmological examination was done and no abnormality found. Blood investigations, chest X-ray, urine examination showed no abnormality. Histopathological examination was done which revealed mild hyperkeratosis. As it is not confirmatory and does not help in making the diagnosis, we made a diagnosis of erythroderma due to X-linked ichthyosis as there were components of history of consanguinity and prolonged labor and examination showed cryptorchidism and generalized scaling with flexural involvement. The patient was prescribed emollient and urea 10% cream and after 4 weeks he showed improvement in scaling and oral retinoid was not needed.

Figure 1

Generalized scaling with erythema over cheeks

Figure 2

Generalized scaling with flexural involvement

Figure 3

Cryptorchidism

Discussion

X-linked recessive ichthyosis (XLRI) affects male offspring who inherit an X chromosome bearing a mutated steroid sulphatase gene at the distal end of the short arm from their asymptomatic carrier mother. In 75% of cases, scaling is evident within the first week of life,[4] but 6% develop scaling after the age of 1 year.[14] A prominent peeling episode at this stage is characteristic. The scaling tends to increase throughout childhood, often spreading up from the lower legs to the trunk. Scaling in XLRI is most prominent on the extensor surfaces of the upper arms, the abdomen, outer thighs and around the lower legs.[1] In contrast to ichthyosis vulgaris, the flexures may be involved.[1] The face, scalp, axillae, flexor aspects of the limbs and dorsal hands and feet may show light grey scaling but the palms and soles are spared. Various extracutaneous abnormalities have been noted in some patients with an increased incidence of testicular maldescent.[5] Corneal dot, thread-like or comma-shaped opacities detected with the slit-lamp microscope, occur in 24–100% of adult patients. They are usually of no functional significance but a minority suffer from mild keratitis.[6789] Pregnancies often ended in prolonged labor, and the underlying defect, placental STS deficiency, was identified. Clinically, XLRI may resemble ichthyosis vulgaris or mild lamellar ichthyosis.[1] Erythroderma is commonly seen in lamellar ichthyosis and non-bullous ichthyosiform erythroderma.[3] There was no history of any collodion membrane at birth which is usually present in lamellar ichthyosis and non-bullous ichthyosiform erythroderma babies. There was no evidence of any large dark scales over the lower limbs or flexural accentuation. This patient presented with undescended testis and history of prolonged labor and consanguinity. But the typical scales of X-linked ichthyosis was not present, rather erythroderma with involvement of flexures, palms and soles.

The other causes of erythroderma are dermatitis of various causes, especially atopic dermatitis, seborrheic dermatitis and Langerhans cell histiocytosis in this age group, pityriasis rubra pilaris, drugs, malignancy, psoriasis, and Norwegian scabies. Pityriasis rubra pilaris presents as erythroderma but this case does not have any islands of sparing which remains present even in erythroderma. There was no history of drug intake prior to scaling. There were no biochemical and laboratory abnormalities and malignancy and Langerhans cell histiocytosis was excluded. So, we made a diagnosis of erythroderma due to X-linked ichthyosis on the basis of excluding the other etiologies.

We have not found any case report of erythroderma due to X-linked ichthyosis in Pubmed Central and Google Scholar. Because of the rarity of the presentation of X-linked ichthyosis, it is worth reporting.

What is new?

X-linked ichthyosis presented as erythroderma but it is rare in its variety.