Histological features:
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Hyperkeratosis, papillomatosis, acanthosis
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Giant, coarse keratohyalin granules
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Vacuolization of the granular layer, resulting in cell lysis and subcorneal multiloculated blisters
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Occasionally, deeper granular cells become dense, enlarged, and irregular, and the shaped masses appear to be keratohyaline granules.

Copyright Mitsuhiro Sugiura, M.D.
Clinical features:
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Presents at or shortly after birth with blistering
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With time skin becomes keratotic, verrucous
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Shedding of hyperkeratotic masses results in circumscribed islands of normal-appearing skin
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Involvement of flexural areas
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Palmar and plantar involvement in the PS subtypes
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Secondary pyogenic infections
Mode of Inheritance:
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Autosomal Dominant
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Defect in the genes for keratin 1 and keratin 10
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Causes dysfunction of keratin intermediate filaments which weakens the structurals stability of the keratinocytes
Frequency:
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One case per 200,000-300,000 persons