thickened, compact orthokeratotic cornified layer with no epidermolytic hyperkeratosis. The granular cell layer was normal or slightly increased. Focal parakeratosis was noted. Ki-67 index of keratinocytes, an immunostaining marker for assessing proliferative activity, was 25.5% (control 9.7%). Electron microscopy showed elongated membrane like structures in the superficial granular layer keratinocytes. Many concentric structures formed by curling of the long membrane like structures were also seen in the cornified layer. There were increased lipid droplets in the cornified layer but no cholesterol crystals were found.
The diagnosis was consistent with non-bullous ichthyosiform erythroderma (Ichthyosis Congenital type III).
Treatment and progress
After the collodion membrane was shed, progressive improvement was noted with frequent emollient applications alone. By six months, scaling was limited to the sacral skin only. Systemic treatment was unnecessary.
REVIEW ON NON-BULLOUS ICHTHYOSIFORM ERYTHRODERMA
NBIE is a rare autosomal recessive inflammatory ichthyosis. There is confusion in nomenclature. In the German literature, NBIE is referred as erythrodermic lamellar ichthyosis.
It affects 1:300,000 newborn of all races especially those where consanguinity is common. It is at least twice as common as lamellar ichthyosis.
Over 90% presents as collodion baby. After shedding of collodion membrane, generalized scaly erythroderma is apparent and may persist. Scales are white or grey, light, superficial and semi-adherent: "feathery" on face, arms and trunk but "lamellar" on
lower limbs. A cyclical pattern of scaling occurs with build up and shedding over two to four weeks. Palmoplantar hyperkeratosis is seen in 70% of cases and may cause fissures and contractures. Pityriasis amiantacea or patchy cicatricial alopecia may occur. Ectropion persists into adult life in 30%. Hypoplasia of the nasal and aural cartilages may occur and nail dystrophy with subungual hyperkeratosis or hypoplasia is seen in 50%. Hair, teeth and mucosa are normal. Nail growth and skin healing are rapid. Sweating is absent or markedly reduced due to obstruction of stratum corneum.
In the absence of positive family history, as an autosomal recessive disease, the risk of further affected child is 1: 4.An affected individual will not have affected offspring but half will be carriers. Sporadic mutation occurs with no implication for subsequent pregnancies but there is no means of identifying this.
There is no specific ultra-structural, biochemical or molecular markers for testing. Foetal skin biopsy with amniocyte pelleting at 17 to 22 weeks looking for premature or abnormal keratinisation is possible but unsatisfactory due to phenotypic heterogeneity and multiple biopsies are required. It is however possible to exclude classical lamellar ichthyosis by chorionic villus sampling and mutation testing for transglutaminase-1 gene TGM1.
Aetiology and pathogenesis
Hyperplasia with increased mitoses is noted in NBIE. This is in contrast with lamellar ichthyosis which is a retention ichthyosis. Secondary alteration in differentiation is noted with K6/K16/K17 expressions. There were no consistent changes in epidermal lipid content. There were reports of raised n-alkane in scale lipids. Its role in pathogenesis is now questioned, as there is no known biosynthetic pathway for alkanes in human and carbon dating studies suggested contamination.2
Compact hyperkeratosis and increase in thickness of stratum corneum are noted. There are variable mild parakeratosis, acanthosis, hypergranulosis and
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