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Cases reported "Xeroderma Pigmentosum"
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1/41. Hypoglycinaemia and psychomotor delay in a child with xeroderma pigmentosum.glycine is a nonessential amino acid that serves as both an inhibitory and an excitatory neurotransmitter. Hyperglycinaemia occurs in non-ketotic hyperglycinaemia, a primary defect in the glycine cleavage pathway, and as a secondary feature of several inborn errors of organic acid metabolism. However, specifically low levels of glycine have never been reported. Here we report a child with complementation group C xeroderma pigmentosum (XP) characterized by a splice donor mutation in the XPC gene, multiple skin cancers and specific and persistent hypoglycinaemia. He has cognitive delay, lack of speech, autistic features, hyperactivity and hypotonia, all unexplained by the diagnosis of XP group C, a non-neurological form of the disease. Treatment with oral glycine has improved his hyperactivity. Specific hypoglycinaemia could indicate a metabolic disorder producing neurological dysfunction. Whether it is related to or coincidental with the XP is unclear.- - - - - - - - - - ranking = 1keywords = disorder (Clic here for more details about this article) |
2/41. Atypical fibroxanthoma of the skin and the lower lip in xeroderma pigmentosum.xeroderma pigmentosum (XP) is a rare, usually autosomal recessive disorder related to dna repair defects. Atypical fibroxanthoma (AFX) is a pleomorphic tumour that occurs infrequently on the limbs and trunk in children. We report a child with XP who presented with AFX of the facial skin and the lower lip. The diagnosis of AFX was confirmed using histological and immunohistochemical techniques. We discuss the possibility that ultraviolet-induced damage might be implicated in the pathogenesis of AFX.- - - - - - - - - - ranking = 1keywords = disorder (Clic here for more details about this article) |
3/41. xeroderma pigmentosum variant heterozygotes show reduced levels of recovery of replicative DNA synthesis in the presence of caffeine after ultraviolet irradiation.patients with xeroderma pigmentosum variant show clinical photosensitivity, skin neoplasias induced by ultraviolet light, and defective postreplication repair, but normal nucleotide excision repair. We recently reported an alternative, simple method for the diagnosis of xeroderma pigmentosum variant that measures by autoradiography three cellular markers for dna repair after ultraviolet irradiation: unscheduled DNA synthesis, recovery of rna synthesis, and recovery of replicative DNA synthesis. Among hereditary photosensitive disorders, including other xeroderma pigmentosum groups, cockayne syndrome, and a newly established ultraviolet-sensitive syndrome, only xeroderma pigmentosum variant cells exhibited normal unscheduled DNA synthesis, normal recovery of rna synthesis, but reduced recovery of replicative DNA synthesis (51 +/- 6% the rate relative to normal controls). This reduction of recovery of replicative DNA synthesis was enhanced in the presence of a nontoxic level of caffeine to 36 +/- 5%. In this study we assess the cellular markers in two independent families that included two photosensitive patients that were identified as xeroderma pigmentosum variant. cells from heterozygotic parents showed normal levels of unscheduled DNA synthesis, recovery of rna synthesis, and recovery of replicative DNA synthesis, but reduced rates of recovery of replicative DNA synthesis in the presence of 1 mM caffeine (53 +/- 8% relative to the normal control). Furthermore, with a colony-forming assay, the cells showed normal survival by ultraviolet without caffeine, but slightly reduced survival by ultraviolet with 1 mM caffeine present. In one family, we confirmed inheritance of two heterozygous mis-sense mutations. One mutation is an A-->G transition at nucleotide 1840 that generates a K535E mis-sense mutation. Another mutation is an A-->C transversion at nucleotide 2003 that generates a K589 mis-sense mutation. Each of these mutations were absent in 52 unrelated Japanese individuals. These results suggest that xeroderma pigmentosum variant heterozygotes can be identified by their sensitivity to ultraviolet irradiation in the presence of nontoxic levels of caffeine.- - - - - - - - - - ranking = 1keywords = disorder (Clic here for more details about this article) |
4/41. Cerebro-oculo-facio-skeletal syndrome with a nucleotide excision-repair defect and a mutated XPD gene, with prenatal diagnosis in a triplet pregnancy.Cerebro-oculo-facio-skeletal (COFS) syndrome is a recessively inherited rapidly progressive neurologic disorder leading to brain atrophy, with calcifications, cataracts, microcornea, optic atrophy, progressive joint contractures, and growth failure. cockayne syndrome (CS) is a recessively inherited neurodegenerative disorder characterized by low to normal birth weight, growth failure, brain dysmyelination with calcium deposits, cutaneous photosensitivity, pigmentary retinopathy and/or cataracts, and sensorineural hearing loss. Cultured CS cells are hypersensitive to UV radiation, because of impaired nucleotide-excision repair (NER) of UV-induced damage in actively transcribed DNA, whereas global genome NER is unaffected. The abnormalities in CS are caused by mutated CSA or CSB genes. Another class of patients with CS symptoms have mutations in the XPB, XPD, or XPG genes, which result in UV hypersensitivity as well as defective global NER; such patients may concurrently have clinical features of another NER syndrome, xeroderma pigmentosum (XP). Clinically observed similarities between COFS syndrome and CS have been followed by discoveries of cases of COFS syndrome that are associated with mutations in the XPG and CSB genes. Here we report the first involvement of the XPD gene in a new case of UV-sensitive COFS syndrome, with heterozygous substitutions-a R616W null mutation (previously seen in patients in XP complementation group D) and a unique D681N mutation-demonstrating that a third gene can be involved in COFS syndrome. We propose that COFS syndrome be included within the already known spectrum of NER disorders: XP, CS, and trichothiodystrophy. We predict that future patients with COFS syndrome will be found to have mutations in the CSA or XPB genes, and we document successful use of dna repair for prenatal diagnosis in triplet and singleton pregnancies at risk for COFS syndrome. This result strongly underlines the need for screening of patients with COFS syndrome, for either UV sensitivity or DNA-repair abnormalities.- - - - - - - - - - ranking = 3keywords = disorder (Clic here for more details about this article) |
5/41. Multi-layer amniotic membrane graft for pterygium in a patient with xeroderma pigmentosum.BACKGROUND: xeroderma pigmentosum (XP) is a rare, autosomal recessive, premalignant condition of the skin, and is reported to be associated with ocular surface disorders such as conjunctival malignancy and pterygium. Herein, we report a case of successful management of pterygium with multi-layer amniotic membrane graft (AMG) in a young XP patient. CASE: An 11-year-old Japanese girl, who had been diagnosed as having XP, was referred to us for treatment of her bilateral pterygium. Surgical intervention was attempted for a temporal, presumably fast-growing pterygium in her left eye. Multi-layer amniotic membrane grafting was performed. OBSERVATIONS: The surgery-induced pain and irritation disappeared within a day. The limbal conjunctival autograft survived on the AMG and re-epithelialization over the AMG was completed in 2 weeks. Best corrected visual acuity improved from 20/32 to 20/16 one month postoperatively. During the 1-year follow-up period, no recurrence was noted. CONCLUSIONS: The present case exemplifies that AMG as an adjunct to primary pterygium resection is effective even in a young patient with XP. In addition, multi-layer AMG, which we first demonstrated in this report, seems to be useful for protecting bare sclera and extraocular muscles from mechanical injury.- - - - - - - - - - ranking = 1keywords = disorder (Clic here for more details about this article) |
6/41. Two individuals with features of both xeroderma pigmentosum and trichothiodystrophy highlight the complexity of the clinical outcomes of mutations in the XPD gene.The xeroderma pigmentosum group D (XPD) protein is a subunit of transcription factor tfiih with DNA helicase activity. TFIIH has two functions, in basal transcription and nucleotide excision repair. Mutations in XPD that affect dna repair but not transcription result in the skin cancer-prone disorder, xeroderma pigmentosum (XP). If transcription is also affected, the result is the multi-system disorder trichothiodystrophy (TTD), in which there is no skin cancer predisposition, or in rare cases, XP combined with cockayne syndrome. Up till now there have been no reports of combined clinical features of XP and TTD. We have now identified two patients with some features of both these disorders. One of these, XP189MA, a 3-year-old girl with sun sensitivity, mental and physical developmental delay, has XPD mutations not previously reported, and barely detectable levels of nucleotide excision repair. The other, XP38BR, a 28-year-old woman with sun sensitivity, pigmentation changes and skin cancers typical of XP, has a mutation that has been identified previously, but only in TTD patients with no features of XP. The level of repair of UV damage in XP38BR is substantially higher than that in other patients with the same mutation. With both patients, polarized light microscopy revealed a 'tiger-tail' appearance of the hair, and amino acid analysis of the hair shafts show levels of sulfur-containing proteins intermediate between those of normal and TTD individuals. Our findings highlight the complexities of genotype-phenotype relationships in the XPD gene.- - - - - - - - - - ranking = 3keywords = disorder (Clic here for more details about this article) |
7/41. trisomy 21 mosaicism in two subjects from two generations.In the course of a chromosome fragility investigation on the cancer prone hereditary disorder xeroderma pigmentosum, a low proportion of cells with a 47,XY,+21 karyotype was found in lymphocyte cultures of a patient not showing any down syndrome symptom. The presence of trisomy 21 mosaicism was demonstrated also in peripheral blood of the healthy father and confirmed by "chromosome painting" that allowed a rapid detection of chromosomes 21 on metaphase cells and interphase nuclei. The trisomic cell line was not detected in fibroblast cultures. The analysis of chromosome 21 heteromorphism indicated that in both subjects the mosaic could result from either a diploid or an aneuploid zygote. Since in the trisomic cell line of the father and the son the extra chromosome 21 seems to be the same, a predisposition toward mitotic errors (non-disjunction or anaphase lagging) may be postulated, leading to the recurrent gain or loss of a specific chromosome 21. In order to test the hypothesis of an abnormal mitotic behaviour of the chromosome 21, we investigated the centromere separation index and the DNA restriction pattern in Southern blots probed with satellite DNA sequences specific for chromosome 21 centromere. Both the approaches did not reveal any peculiar feature that may account for the genetically determined proneness to mitotic error observed in the family.- - - - - - - - - - ranking = 1keywords = disorder (Clic here for more details about this article) |
8/41. The treatment of basal skin carcinomas in two sisters with xeroderma pigmentosum.xeroderma pigmentosum (XP) is a rare autosomal recessive disorder that causes defects in the dna repair system. It is characterized by a marked sensitivity to sunlight, and sufferers develop serious sunburns with onset of poikilodermia in the light-exposed skin. Squamous cell carcinomas, basal cell carcinomas (BCCs) and malignant melanomas appear in childhood. Two sisters with XP presented with previously treated facial BCCs. They were treated with imiquimod 5% cream three times weekly, one for 6 weeks and the other for 10 weeks. Although both sisters temporarily discontinued treatment due to severe erythema and erosion, successful long-term clearance was observed with no recurrences in both cases.- - - - - - - - - - ranking = 1keywords = disorder (Clic here for more details about this article) |
9/41. The treatment of basal cell carcinomas in a patient with xeroderma pigmentosum with a combination of imiquimod 5% cream and oral acitretin.xeroderma pigmentosum (XP) is a rare autosomal recessive photosensitive disorder, which results in multiple face, neck and head basal cell carcinomas (BCCs), squamous cell carcinomas and melanomas. A 15-year-old boy with XP presented with multiple facial BCCs previously treated by surgical excision. Standard BCC treatments such as surgery are not ideal for patients with several facial BCCs because of the risk of scarring, and the patient refused further surgery. As an alternative, three times weekly application of imiquimod 5% cream in combination with oral acitretin (20 mg daily) was prescribed for 4-6 weeks. No adverse events were reported during treatment and all tumours had resolved at the 6-month follow up visit, highlighting the therapeutic potential of imiquimod 5% cream.- - - - - - - - - - ranking = 1keywords = disorder (Clic here for more details about this article) |
10/41. xeroderma pigmentosum variant with multisystem involvement.BACKGROUND--xeroderma pigmentosum (XP) is a hereditary disorder characterized by recessive inheritance and elevated rates of skin carcinogenesis. There are seven complementation groups (A through G) for which the genetic defect results in a failure to repair dna damage from UV light and sunlight; one group, the variant, fails to replicate UV-damaged DNA correctly. patients in XP groups A, B, D, and G have associated neurologic problems, the most severe being known as the DeSanctis-Cacchione syndrome. OBSERVATIONS--We describe a patient with XP from consanguineous parents who has severe multisystem involvement similar to that of the DeSanctis-Cacchione syndrome. Extensive laboratory investigation showed that cells from this patient exhibit dna replication after irradiation with UV light that is characteristic of the XP variant. The cells also show normal sensitivity to UV light and normal excision repair, consistent with XP variant classification. The presence of the neurologic symptoms is quite unusual in an XP variant. CONCLUSION--Our patient clearly fits into the XP variant category based on normal survival, caffeine toxic reaction, photoproduct excision and repair, and the deficient replication of UV-damaged DNA. This patient seems to be rare, however, among XP variants in displaying severe neurologic symptoms. Because of the consanguineous parents, the possibility that some of this patient's findings are from non-XP-related abnormalities must also be entertained. However, other consanguineous patients with XP variant, eg, XPIOCA, have been described who do not show neurologic abnormalities. In view of the difficulty of defining an XP group from clinical symptoms alone, we urge the term xeroderma pigmentosum variant be used only in the context of the laboratory studies of patients with XP that contain normal repair but deficient semiconservative replication of UV-damaged DNA.- - - - - - - - - - ranking = 1keywords = disorder (Clic here for more details about this article) |
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