Ichthyosis

Disease	Pathogenesis	Pathology	ClinicalFeatures/Treatment
Ichthyoses	increasesed cohesiveness,abnormal keratinization, increased basal cell proliferation	abnormally thickened stratumcornerum, hyperkeratosis, thin nucleated epidermis	coarse, fish-like scales
Ichthyosis Vulgaris	Autosomal Dominant - reduced or absent keratohyaline granules in epidermis attenuated stratum granulosum - reduced profilaggrin	loose stratum corneum,basket-weave appearance	most common, begins earlychildhood, small white scales on extensor surfaces of extremities andon trunk and face, lifelong disease abnormalities in lipid metabolism from drugs or other diseases
X- linked ichthyosis	deficiency of sterioid sulfatase steroid sulfatase degrades cholesterol sulfate	persistent cohesion of stratumcorneum
Lamellar ichthyosis	autosomal recessive - disorderof cornification, defect in lamellar body secretion	increased cohesivenss of stratumcorneum, numerous keratinosomes, abnormally large amount ofintercellular substance	severe and generalized ichthyosis
Epidermolytic hyperkeratosis	autosomal dominant, mutation inkeratin genes in suprabasal epidermis	faulty assembly of keratintonofilaments, impaired insertion into desmosomes, prevents normaldevelopment of cytoskeleton -> epidermal lysis and vesicles	generalized erythroderma,blistering, ichthyosiform skin

Source: Rubin's Pathology 4th Edition