1/32. Epidermolytic palmoplantar keratoderma due to a novel type of keratin mutation, a 3-bp insertion in the keratin 9 helix termination motif.Epidermolytic palmoplantar keratoderma (EPPK) is an autosomal dominant genodermatosis characterized by diffuse keratoderma, typically with an erythematous border. Histologically, palmoplantar epidermis shows suprabasal cytolysis and ultrastructurally, tonofilament aggregation with overlying epidermolytic hyperkeratosis. Mutations in the KRT9 gene, encoding keratin 9 (K9), a cytoskeletal protein expressed exclusively in suprabasal keratinocytes of palmoplantar epidermis, have been reported to cause EPPK. To date, all KRT9 defects reported in EPPK have been missense mutations in exon 1, which encodes the start of the alpha-helical rod domain. However, based on studies of other keratin disorders, it was postulated that mutations at the other end of the rod domain might also produce the EPPK phenotype. Here, we report the first mutation in the 2B domain of KRT9, 1362ins3, leading to an insertion of histidine in the helix termination motif of the K9 polypeptide. Insertional mutations have not been previously described in keratins. The phenotype of this case is similar to EPPK caused by 1A domain mutations, demonstrating that mutations in either of the helix boundary motif sequences of K9 are detrimental to keratin function and keratinocyte structure.- - - - - - - - - - ranking = 1keywords = dermis (Clic here for more details about this article) |
2/32. R162W mutation of keratin 9 in a family with autosomal dominant palmoplantar keratoderma with unique histologic features.Recurrent R162W mutation ofkeratin 9 has been reported in multiple families with epidermolytic hyperkeratosis (EHK)-type hereditary palmoplantar keratoderma (PPK). Recently, we have observed a family whose members showed autosomal-dominant PPK with unique histologic features such as rounded, dissociated, and slightly eosinophilic keratinocytes at the middle spinous and granular layers of epidermis, but without the distinct EHK phenotype. To investigate the genotype-phenotype correlation in this family, we searched for a mutation of keratin 9 and found R162W substitution in the coiled 1A region. This mutation was not detected in 50 control individuals. These results may further our understanding of the pathogenesis of EHK.- - - - - - - - - - ranking = 0.5keywords = dermis (Clic here for more details about this article) |
3/32. Palmoplantar keratoderma (Voerner) with composite keratohyalin granules: studies on keratinization parameters and ultrastructures.A case of the Voerner type palmoplantar keratoderma was studied for abnormalities of keratinization parameters. An enzyme and materials used to build the marginal band or cellular envelope of the cornified cell were all abnormally expressed; i.e. transglutaminase I (TGK), loricrin, and involucrin were abnormally immunostained. In the normal controls, their expression was limited to the upper epidermis, mainly in the granular layer. In the lesional skin, they were detected from the suprabasal layer to the lower horny layer. Filaggrin, the protein of the keratohyalin granule, was also expressed more widely than in controls. Ultrastructural abnormalities included a significantly higher frequency of composite keratohyalin granules than controls, early formation of a marginal band in the midepidermis, and, most remarkably, the clumping of tonofilaments causing vacuolization of the cytoplasm of affected keratinocytes.- - - - - - - - - - ranking = 1keywords = dermis (Clic here for more details about this article) |
4/32. Transgrediens et progrediens palmoplantar keratoderma (Greither's disease) with particular histopathologic findings.We describe a patient with transgrediens et progrediens palmoplantar keratoderma (Greither's disease). Ten of the 25 members of this patient's family in six consecutive generations were affected by the disorder. The pedigree was consistent with an autosomal dominant inheritance pattern, with variable penetrance. The proband's physical examination showed typical signs of Greither's disease. The most striking findings were seen in histopathologic study and consisted of round, focal areas of orthohyperkeratosis located on delled areas of the epidermis. These histopathologic features were present in both the lesions of the palms and dorsum of the hands. We review the clinical manifestations and histopathologic findings of this particular variant of palmoplantar keratoderma and the differential diagnosis.- - - - - - - - - - ranking = 0.5keywords = dermis (Clic here for more details about this article) |
5/32. A mutation in the V1 domain of K16 is responsible for unilateral palmoplantar verrucous nevus.Palmoplantar keratodermas are a group of heterogeneous diseases characterized by thickening, and marked hyperkeratosis, of the epidermis of the palms and soles. Palmoplantar keratodermas can be divided into four major classes: diffuse, focal, punctate, and palmoplantar ectodermal dysplasias. All forms are genetic diseases inherited as autosomal dominant disorders. We studied a patient exhibiting a localized thickening of the skin in parts of the right palm and the right sole, following Blaschko's lines, that does not fit into any classes already described. We sequenced the keratin 16 cDNA derived from skin biopsy material from affected and non affected palms. The keratin 16 cDNA sequence from lesional epidermis showed a 12 base pair deletion (309-320del), which deletes codons 104-107. The mutation is predicted to delete four amino acids, GGFA, from the V1 domain of the keratin 16 polypeptide, close to the 1A domain. Full-length keratin 16 cDNA sequence derived from the unaffected palm was completely normal, consistent with a postzygotic mutation as is suggested by the mosaicism observed. We defined this new clinical entity, "unilateral palmoplantar verrucous nevus", rather than localized or focal epidermolytic palmoplantar keratodermas, as the lesions are present only on one side of the body and follow Blaschko's lines. This study is a report of a mosaic mutation in keratin 16 and also the association of a mutation in the V1 domain of a type I keratin associated with a human disease.- - - - - - - - - - ranking = 1keywords = dermis (Clic here for more details about this article) |
6/32. Punctate keratoderma-like lesions on the palms and soles in a patient with chloracne: a new clinical manifestation of dioxin intoxication?We report what we believe to be a novel skin manifestation of dioxin intoxication. A 30-year-old woman with 2,3,7, 8-tetrachlorodibenzo-p-dioxin levels of 144,000 pg g-1 blood fat presented with severe chloracne that affected the entire integument. She also exhibited acral granuloma annulare-like lesions and distal onycholysis and, at a later time point, showed signs of hypertrichosis, as well as brownish-grey hyperpigmentation of the face. In addition, she developed punctate keratoderma-like lesions on the palms and soles. These lesions were negative for human papillomavirus and histologically characterized by cone-shaped hyperkeratoses invaginating, but not penetrating, into the dermis. Squamous syringometaplasia of the eccrine glands was observed in the immediate vicinity of these lesions. Both clinically and histologically these alterations are essentially indistinguishable from what is described as keratosis punctata palmaris et plantaris (KPPP). Although a fortuitous coincidence of chloracne and KPPP cannot be formally excluded, the possibility exists that in our patient toxic levels of dioxin were causally involved in this disorder of keratinization.- - - - - - - - - - ranking = 0.5keywords = dermis (Clic here for more details about this article) |
7/32. Huriez syndrome: case report with a detailed analysis of skin dendritic cells.We report a 60-year-old man with familial scleroatrophic syndrome of Huriez who developed squamous cell carcinomas on the affected skin of the right palm. Immunohistochemical analysis showed a marked reduction in the number of CD1a , Lag and S100 epidermal langerhans cells, but not of CD1b and factor xiiia dermal dendritic cells, limited to palmoplantar skin. The Langerhans cell depletion was not associated with an abnormal skin content of mRNA for factors involved in Langerhans cell development or recruitment in the epidermis, including granulocyte/macrophage colony-stimulating factor, transforming growth factor-beta1 and macrophage inflammatory protein-3alpha. The results indicate that other as yet unknown mechanisms may account for the reduced number of langerhans cells in the affected skin of such patients.- - - - - - - - - - ranking = 0.5keywords = dermis (Clic here for more details about this article) |
8/32. Composite keratohyaline granules in striate keratoderma.The gross, light microscopic, and ultrastructural findings in a 55 year old man was striate keratoderma are presented. There was no family history of the disease. The lesions developed in his late teens and early adult years, and consisted of progressively worsening, raised, hyperkeratotic, linear plaques on the palm and volar surface of the third and fifth fingers bilaterally. There were also painful callosities on both heels, and thick, raised plaques on the heels and lateral plantar surfaces. The epidermis was papillomatous and acanthotic, with marked orthokeratosis, minimal parakeratosis, and a very thickened granular layer. No epidermolysis was seen. Electron microscopy showed increased tonofibrils in the stratum spinosum arranged in wavy, parallel bundles and a granular layer in which normal Odland bodies were present. However, the keratohyaline granules were large, with rounded borders and a striped, alternating, dark and light content characteristic of composite granules. There was diminished contact of the granules with tonofibrils. The transition to the stratum corneum was abrupt. The ultrastructural and genetic features of keratodermas, with special emphasis on the striate type, are reviewed.- - - - - - - - - - ranking = 0.5keywords = dermis (Clic here for more details about this article) |
9/32. An Indian case of keratoderma hereditarium mutilans (Vohwinkel's syndrome) associated with ichthyosiform dermatosis.Keratoderma hereditarium mutilans (KHM) or Vohwinkel's syndrome (VS) is usually inherited as an autosomal dominant disease, but a recessive type has occasionally been described. We report a 19-year-old male born to consanguineous parents, who presented with KHM associated with generalized ichthyosiform dermatosis. On examination, his generalized ichthyosiform dermatosis was accompanied by severe 'honey comb' like palmoplantar keratoderma and marked hyperhidrosis. Bilateral fifth toes showed complete constricting bands just distal to the metatarsophalangeal joints leading to pseudoainhum. The histopathologic examination of a biopsy from the sole showed hyperkeratosis, marked parakeratosis, hypergranulosis, acanthosis, and a few mononuclear cells in the papillary dermis, consistent with the diagnosis of KHM. Several hereditary disorders may show varying degrees of hyperkeratosis and constriction of digits; their differentiating features are discussed. This case is reported for its rarity and interesting associated findings.- - - - - - - - - - ranking = 0.5keywords = dermis (Clic here for more details about this article) |
10/32. Olmsted syndrome: report of a case with study of the cellular proliferation in keratoderma.Olmsted syndrome is a rare disorder that consists of sharply marginated keratoderma of the palms and soles, constriction of digits and toes that may result in spontaneous amputation of the distal phalanges, hyperkeratotic plaques around the body orifices, onychodystrophy, and other less common cutaneous and extracutaneous anomalies. Although some patients had other affected family members, most cases of Olmsted syndrome seem to be of sporadic occurrence. We describe a patient with the characteristic features of Olmsted syndrome. The symptoms consisted of diffuse transgrediens palmoplantar keratoderma and keratotic plaques around the mouth and nose. Our patient also had the associated anomalies of hyperhidrosis of the palms and soles and congenital deaf-mutism. Histopathologic study of the keratoderma demonstrated epidermal hyperplasia with acanthosis, papillomatosis, and orthokeratotic hyperkeratosis.Immunohistochemical study showed more basal and suprabasal keratinocytes of the epidermis with immunoreactivity for Ki-67 marker when compared with the keratinocytes of the epidermis of the adjacent non-involved skin. These results support the notion that Olmsted syndrome is a hyperproliferative disorder of the epidermis.- - - - - - - - - - ranking = 1.5keywords = dermis (Clic here for more details about this article) |
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