SEARCH · PubMed Health
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Explore the source record for details and available documents.
Ichthyosis bullosa of Siemens is an autosomal dominant disease characterized by mild hyperkeratosis and blistering. Autosomal dominant ichthyosis exfoliativa is a recently described disease with clinical features similar to ichthyosis bullosa of Siemens, but in contrast to ichthyosis bullosa of Siemens no histologic signs typical for epidermolytic hyperkeratosis are observed. We used linkage analysis to test whether keratin gene mutations might underlie both diseases. This analysis showed linkage of both disorders with the region of chromosome 12 in which the keratin type II gene cluster is located. The keratin type I gene cluster on chromosome 17 is excluded. These data, combined with clinical observations, strongly suggest that the genes coding for keratin 1 or keratin 2e, both expressed in the suprabasal compartment of the epidermis and located in the type II gene cluster, are candidate genes for ichthyosis bullosa of Siemens and ichthyosis exfoliativa.
Thirty cases of X-linked ichthyosis (XLI) and 32 cases of ichthyosis vulgaris (IV) were diagnosed by measuring the steroid sulphatase activity of peripheral blood lymphocytes or the electrophoretic mobility of serum LDL or both. The clinical features of the two conditions were then compared. In both diseases 60-66% of patients had a family history of the condition. Ichthyosis was noted at birth or immediately afterwards in 59% of the patients with XLI while it appeared in infancy in 68% of those with IV. Scales were mostly large and brown or dark brown in patients with XLI, while the majority of patients with IV had small brown or light brown scales. The distribution of the ichthyotic lesions differed in the two types of ichthyosis. On the trunk, the abdomen was more severely involved than the back in 63% of the cases with the XLI, whereas the back was more scaly than the abdomen in 44% of those with IV. On the extremities, the extensor surface was more severely affected than the flexor surface in both types. X-linked ichthyosis was characterized by the presence of lesions in the pre-auricular area, which were found in 93% of the cases with XLI, while only 17% of the IV patients had ichthyotic lesions at this site. Involvement of the preauricular area could be an important clinical feature for distinguishing XLI from IV.
We describe one type of the heterogeneous ichthyosis congenita group, inherited autosomal-recessively, noting its clinical and ultrastructural features based on the findings in a female patient, aged 30 at the time of first clinical and ultrastructural investigation, and supplemented with those of eight further patients, aged 2 to 22 years. Clinically this keratinization disorder was characterized by a generalized congenital ichthyosis with a reticulate skin pattern pronounced in a variable degree of severity, also involving the large flexures and the face, palms, and soles. Typical ultrastructural criteria were membrane structures, abnormal vesicular keratinosomes, vesicular complexes, and membrane-bound vacuoles within the cytoplasm of the granular cells, partly retained in the horny layer. A successful therapy with retinoids resulted in a complete removal of the hyperkeratoses but left the striking skin pattern unchanged. The morphological peculiarities remained unaltered as well. They are independent of the localization of the biopsies, of age and sex of the patients, and of oral and local treatment. Based on the clinical and ultrastructural features, this scaling disorder can be delineated against all other inherited ichthyoses and was termed ichthyosis congenita type III. A new nomenclature contributing to a distinct classification within the heterogeneous ichthyosis congenita group is discussed.
There is an expanding list of syndromes that combine ichthyosis with neuroectodermal and mesodermal defects. We present the case of a young woman with the following features: lamellar ichthyosis, dwarfism, mental retardation, nail and dental abnormalities, unusual facies, poor sexual maturation, punctate cataracts, and hair shaft abnormalities. There were no neurologic or auditory defects. Hair examination revealed pili torti, trichoschisis, bright and dark bands with polarizing microscopy, and a low hair sulfur content. The patient did not have aminoaciduria or immunoglobulin abnormalities. We believe that this case is a link between the ichthyosis-associated syndromes and the group of syndromes that have in common abnormal hair with clean transverse fractures (trichoschisis) and low sulfur content. A more complete examination of the hair in other patients with ichthyosis and associated abnormalities will probably reveal more patients with this new syndrome.
We have studied 16 men, from 10 unrelated Italian families, affected by steroid suphatase (STS) deficiency, which is the basic defect of X-linked ichthyosis (XLI). The patients' clinical diagnoses were of either isolated ichthyosis or ichthyosis associated with Kallmann syndrome (KS) (hypogonadotropic hypogonadism and anosmia). DNA from patients and their relatives was analysed by Southern blotting followed by hydridization with an STS cDNA probe. None of the patients affected by either XLI or XLI/KS showed any hybridization signal, thus revealing a deletion in the STS gene. We suggest that a gene deletion may be the most common molecular defect involved in XLI and that the syndrome XLI/KS may be due to a deletion of both the STS and the KS loci.
Recently, autosomal-dominant lamellar ichthyosis (ADLI) has been shown to be a new genetic trait with clinical and histologic features similar to those of autosomal-recessive lamellar ichthyosis. In two patients affected with ADLI, the malpighian keratinocytes showed ultrastructural signs of increased cellular metabolism. The tonofilaments and keratohyaline granules were regular in structure and number. However, as a distinctive ultrastructural feature, a prominent transforming zone was found between the granular and horny layers. Moreover, a normal keratin pattern and only a limited number of lipid inclusions were observed in the stratum corneum. Thus, ADLI can be distinguished from the autosomal-recessive forms of lamellar ichthyosis, permitting a correct diagnosis when genetic counselling has to be given in sporadic cases.
Twenty-one patients with ichthyosis were classified as either ichthyosis vulgaris (IV) (five cases) or recessive X-linked ichthyosis (RXLI) (sixteen cases) by using a steroid sulphatase assay of plantar callus and peripheral leukocytes. The patients had presented with various clinical manifestations, which had resulted in some initial misdiagnoses. Cases which initially resemble IV may in fact be RXLI, although we found that if a case is initially diagnosed as RXLI it is unlikely to be a case of IV.
Two collodion baby girls with disorder evolving into lamellar ichthyosis were followed by light and electron microscopy. Light microscopically, the neonatal colloidion skin was characterized by a thick compact stratum corneum which was PAS positive in its upper two thirds, by a thin stratum granulosum and by a non-acanthotic stratum spinosum with normal mitotic activity. Electron microscopically, the upper stratum corneum appeared pathological, whereas the lower part was normal except for some minor parakeratosis. The main alterations in the underlying stratum granulosum were diminished tonofibrils and keratohyalin. Biopsy specimens taken at the age of 2 weeks were typical for lamellar ichthyosis and showed hyperkeratosis with focal parakeratosis, a thickened stratum granulosum in which the cellular content of keratohyalin and tonofibrils was moderately diminished, and acanthosis with increased mitotic activity. It appears that the ultrastructural changes of the stratum granulosum, seen in lamellar ichthyosis, are already present in the collodion skin of the newborn, at a time when the epidermis does not yet show an increase in mitotic activity.
The clinical and histologic distinction between X-linked recessive and autosomal dominant ichthyosis was studied by evaluating 12 classical differential parameters in 85 patients. Thirty-three of them had X-linked and 52 autosomal dominant ichthyosis. Eight of these parameters were generally helpful in the differential diagnosis: age of onset, severity of involvement, scale size, chapping of hands and feet, atopic background, influence of warm weather, corneal opacities and state of the granular layer. Involvement of skin folds, keratosis pilaris, increased palmo-plantar markings and improvement with age were unreliable. In the literature, age of onset and corneal opacities were additionally found unreliable; the histology was of limited value in two reports. Therefore, we concluded that the herein evaluated differential criteria seem to be valid mainly when considering groups of patients. For the individual case, an error in diagnosis, particularly in X-linked ichthyosis, is not rare when relying solely on these criteria. When in doubt, determination of steroid sulphatase activity is mandatory.
Steroidsulfatase and arylsulfatase C were determined in fibroblasts and/or leukocytes of patients affected with different types of ichthyosis. Of the 21 patients studied, 11 showed clinical characteristics of X-linked ichthyosis (XLI) and a deficiency of these 2 enzymatic activities. Patients affected with other types of ichthyosis showed no enzymatic deficiency. In XLI families diagnosis of heterozygotes was performed by enzymatic measurements in the 5 patients' mothers studied. In 2 families enzymatic activities were studied in patients' sisters. The validity of these different enzymatic measurements is discussed.
The present study analyzes the accuracy of the clinical diagnosis of X-linked ichthyosis (XLI) vs ichthyosis vulgaris (IV), in a sample of Mexican patients. The study was double blind, using steroid sulfatase (STS) activity as the golden standard. Twenty male patients were included; 16 corresponded to XLI and 4 to IV. The clinical diagnosis was correct in 9 of the 16 XLI cases (56%) and in 2 of the 4 IV cases (50%). Some clinical findings in XLI, such as cryptorchidism in patients and delayed labor in their mothers, were important features for diagnosis. Statistical analysis of the results showed: among physicians (n = 2) Kappa value 0.50, specific concordance 0.40, and absolute concordance 0.75; other values were sensibility 0.56, specificity 0.50, positive predictive value 0.82, negative predictive value 0.22, accuracy 0.55, prevalence 0.80. In conclusion, the differential diagnosis of XLI and IV is very difficult, and we consider that this is not explained either by personal skills or by other conditions. It could be attributed to the similarities in skin manifestations of these two diseases. The performance of the STS assay is imperative in order to correctly diagnose the disease and offer adequate genetic counseling.
Nonbullous congenital ichthyosiform erythroderma (CIE) and classic lamellar ichthyosis (LI) can be distinguished by clinical, histopathologic, and biochemical findings reported herein. Whereas all patients with CIE (n = 12) had fine white scales, they were heterogeneous with respect to degree of erythroderma, ectropion, and prognosis. In contrast, all patients with LI (n = 6) had large, dark, platelike scales, severe ectropion that showed no improvement with age, and minimal erythroderma. Although the stratum corneum of patients with LI was two to three times thicker than that of those with CIE, the latter group demonstrated more acanthosis, parakeratosis, hypergranulosis, and less prominent dermal capillaries. Studies of scale-lipid content have indicated biochemical correlates of this clinical heterogeneity. These clinical, histologic, and biochemical findings provide useful guidelines to differentiate CIE from LI and strongly suggest that autosomal recessive primary ichthyosis comprises two distinct diseases.
A generalized ichthyosis with an associated spastic syndrome of the lower extremities, clinically suggestive of Sjögren-Larsson syndrome, was observed in a Tunisian boy. The fatty acid analysis of the serum phospholipids revealed significant abnormalities in the fatty acid pattern of phospholipids. However, the alterations observed were different from those reported in Sjögren-Larsson syndrome. We report light and electron microscopic changes in the ichthyotic skin of this patient, which have not been previously reported in lamellar ichthyosis and in Sjögren-Larsson syndrome. The epidermis was moderately hyperplastic and covered with a thick, compact, orthokeratotic stratum corneum. The stratum spinosum was strikingly altered in some areas. Varying numbers of keratinocytes contained big vacuoles, measuring often up to the size of the nuclei; the vacuoles, were well limited but only partially lined by a membrane, they were empty or contained small amounts of a flaky material. Attempts to stain the vacuoles with PAS, Alcian blue and Fettrot were negative. Etretinate treatment produced a marked shedding of the horny layer without significant improvement of the clinical appearance. The described microscopical alterations of the epidermis remained mostly unchanged during treatment, but, in addition, a marked oedema and vacuolisation of the upper stratum granulosum was observed.
4 cases with congenital hyperkeratotic lesions localized on the palms and soles, occurring in three generations of one family, were observed. The atrophic, hyperkeratotic lesions accompanied by anhidrosis were dirty yellowish-brown coloured, with an ill-defined border but without any erythematous or pigmented halo. Further clinical findings were conspicuous dryness, adherent scale formation, fissurings and parchment paper-like luster. Histological findings were identical to those of ichthyosis vulgaris, with an absence of eccrine sweat glands. Hence, this type of hyperkeratosis can be distinguished from other types of inherited palmoplantar keratosis. For this peculiar form of dominantly inherited palmoplantar keratosis, the author proposed the new name 'ichthyosis vulgaris palmaris et plantaris dominans'.
The growth, differentiation, and regeneration of epidermal cultures from patients with X-linked and autosomal dominant ichthyosis and normal individuals were compared. Cell proliferation was studied by combining the technique of fluorescence-activated cell sorting with [3H]thymidine labelling and autoradiography. As in normal epidermal cultures, a marked heterogeneity in the labelling intensity of S-phase cells was observed in the ichthyotic cultures with totally unlabelled as well as very strongly labelled cells. However, in contrast to normal cultures, by far the largest proportion of S-phase cells in the ichthyotic cultures were very strongly labelled with a corresponding, severe reduction in the proportion of un- and weakly labelled cells. The increased labelling intensity of S-phase cells was observed in primary as well as in regenerating cultures, although it was most pronounced in the latter case. There was no difference between cultures from the two types of ichthyotic skin. The morphologic differentiation in the cultures was assessed by measurement of mean diameter of sorted S-phase cells and by quantitation of cornified envelop formation. Both parameters were reduced in the ichthyotic cultures, compared with normal ones. Taken together, these findings are indicative of a hyperproliferative state in the ichthyotic cultures.
Explore the source record for details and available documents.
Explore the source record for details and available documents.