| • | pathogenesis (of most) = defective epidermal proteins or lipid |
| • | ichthys – fish from Greek |
4 categories of ichthyoses:
| • | retention hyperkeratosis (spares flexures mnemonic - vulgar sex spares the flex) |
| • | hyperproliferative (involves the flexures) |
| • | lamellar ichthyosis (collodion baby) |
| • | congenital ichthyosiform erythroderma (collodion baby) |
mnemonic: makes sense because the moist flexures and the friction of the flexures get rid of the retained hyperkeratosis
| 2. | ichthyosiform syndromes (all 3 autosomal recessive) |
| • | Sjogren-Larsson syndrome |
| 3. | related disorders of cornification |
| • | malignancy – most commonly reported with Hodgkin’s disease |
| • | non-malignant diseases – AIDS, malnutrition/malabsorption, CRF, Hansen's disease |
| • | drug induced – cholesterol lowering drugs (Triparanol and nicotinic acid) (but epidermal sterol metabolism is independent of serum sterol activity) |
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Autosomal Recessive:
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Autosomal Dominant:
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X-linked recessive:
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collodion baby
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epidermolytic hyperkeratosis
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X-linked ichthyosis
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ichthyosis vulgaris
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Darier’s disease
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harlequin fetus
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CHILD syndrome
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Sjogren-Larsson
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Netherton syndrome
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trichothiodystrophy
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Refsum's disease
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