Histology granular layer

Histologically, congenital ichthyoses are characterized by a variable degree of dense hyperkeratosis with occasional focal parakeratosis, a normal to thickened granular layer, moderate acanthosis and a mild mononuclear infiltrate in the upper dermis. Increased proliferative activity is also demonstrated by many mitotic figures. 

Histopathologically there is hyperkeratosis, a prominent granular layer and rete ridges. It resembles the picture observed in lamellar ichthyosis, but with few mitoses. In our opinion, the clinical and histologic appearances of sex-linked ichthyosis, as well as its natural history, are poorly differentiated from those found in autosomal recessive lamellar ichthyosis. In fact, the only differences are that, in the sex-linked type, the palms, soles and epidermal proliferation rates are normal. In practice, however, female patients may be encountered exhibiting the clinical features of Ichthyosis nigricans. 

Immunodeficiency with short-limbed dwarfism is an autosomal recessive disorder ". Antibody and cell-mediated immunity is defective. From the first few weeks after birth, there is a severe scaling erythroderma with large coarse scales (Figure 15.1) some areas are free, in others the symptoms rapidly subside for short periods of time then reappear. Histologically the stratum corneum shows parakeratosis and hyperkeratosis and contains some neutrophils. There is an absence of the granular layer, papillomatosis and a moderate acanthosis with many mitoses. There is a mononuclear infiltrate in the upper and papillary dermis. 

Histologically there is hyperkeratosis with scattered parakeratosis, moderate acanthosis and decreased granular layer. A perivascular lympho-cytic infiltrate is observed in the dermis. 

Erythrokeratodermia variabilis of Mendes da Costa is an autosomal dominant inherited dermatosis which affects both sexes. It starts at birth or in early infancy with moderate erythrodermic areas changing in size and location from day to day, and rapidly scaling lamellae particularly at the borders later on, fixed configurate hyperkeratotic plaques arise as such on normal skin. The face, anterior aspect of the body, buttocks and limbs are the commonest sites. The palms and soles may be thickened. Histologic sections show hyperkeratosis with focal parakeratosis, normal granular layer, moderate papillomatosis and acanthosis and a mild perivascular mononucleated infiltrate in the upper dermis. The rate of proliferation is normaP . The condition improves with age. 

The initial double blind placebo controlled trials were extended for an additional six months, but further histological assessments performed in a similar fashion showed reversal of some of the earlier changes [47]. The stratum comeum compaction decreased from 90% at 24 weeks to 51% at 48 weeks, the epidermal thickness decreased to 6% less than pre-treatment levels, and the granular layer thickness was reduced after 48 weeks to 25% over baseline compared to 60% increase at 24 weeks. Results of periorbital biopsies performed in 27 patients at baseline, 6,12, and 48 months [44] were available and showed a slightly increased prevalence of stratum comeum compaction compared with baseline and 12 months and a normal granular layer and epidermal thickness. Further ultra-stmctural studies [49, 50] showed increased anchoring fib-... 

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