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Alopecia areata is an immune-mediated disorder, occurring with the highest observed frequency in the rare recessive autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) syndrome caused by mutations of the autoimmune regulator (AIRE) gene on chromosome 21q22.3. We have previously detected association between alopecia areata and a single nucleotide polymorphism (SNP) in the AIRE gene in patients without APECED, and we now report the findings of an extended examination of the association of alopecia areata with haplotype analysis including six SNPs in the AIRE gene: C-103T, C4144G, T5238C, G6528A, T7215C and T11787C. In Caucasian groups of 295 patients and 363 controls, we found strong association between the AIRE 7215C allele and AA [P = 3.8 x 10(-8), OR (95% CI): 2.69 (1.8-4.0)]. The previously reported association between AA and the AIRE 4144G allele was no longer significant on correction for multiple testing. The AIRE haplotypes CCTGCT and CGTGCC showed a highly significant association with AA [P = 6.05 x 10(-6), 9.47 (2.91-30.8) and P = 0.001, 3.51 (1.55-7.95), respectively]. To select the haplotypes most informative for analysis, we tagged the polymorphisms using SNPTag software. Employing AIRE C-103T, G6528A, T7215C and T11787C as tag SNPs, two haplotypes were associated with AA; AIRE CGCT and AIRE CGCC [P = 3.84 x 10(-7), 11.40 (3.53-36.9) and P = 3.94 x 10(-4), 2.13 (1.39-3.24) respectively]. The AIRE risk haplotypes identified in this study potentially account for a major component of the genetic risk of developing alopecia areata.

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Germline mutations of the fumarate hydratase (FH, fumarase) gene are found in the recessive FH deficiency syndrome and in dominantly inherited susceptibility to multiple cutaneous and uterine leiomyomatosis (MCUL). We have previously reported a number of germline FH mutations from MCUL patients. In this study, we report additional FH mutations in MCUL and FH deficiency patients. Mutations can readily be found in about 75% of MCUL cases and most cases of FH deficiency. Some of the more common FH mutations are probably derived from founding individuals. Protein-truncating FH mutations are functionally null alleles. Disease-associated missense FH changes map to highly conserved residues, mostly in or around the enzyme's active site or activation site; we predict that these mutations severely compromise enzyme function. The mutation spectra in FH deficiency and MCUL are similar, although in the latter mutations tend to occur earlier in the gene and, perhaps, are more likely to result in a truncated or absent protein. We have found that not all mutation-carrier parents of FH deficiency children have a strong predisposition to leiomyomata. We have confirmed that renal carcinoma is sometimes part of MCUL, as part of the variant hereditary leiomyomatosis and renal cancer (HLRCC) syndrome, and have shown that these cancers may have either type II papillary or collecting duct morphology. We have found no association between the type or site of FH mutation and any aspect of the MCUL phenotype. Biochemical assay for reduced FH functional activity in the germline of MCUL patients can indicate carriers of FH mutations with high sensitivity and specificity, and can detect reduced FH activity in some patients without detectable FH mutations. We conclude that MCUL is probably a genetically homogeneous tumour predisposition syndrome, primarily resulting from absent or severely reduced fumarase activity, with currently unknown functional consequences for the smooth muscle or kidney cell.

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Reports of allergic reactions following treatment with systemic corticosteroids are rare, despite their widespread use. A 47-year-old man developed widespread urticaria, resistant to antihistamines, coinciding with injections of local anaesthetic and methylprednisolone for cervical spondylosis. He underwent immediate and delayed hypersensitivity tests. Intradermal tests showed immediate-type sensitivity to methylprednisolone and hydrocortisone. Patch tests were positive to 21 of 26 corticosteroids tested. A diagnosis of both an immediate and a delayed-type hypersensitivity to corticosteroids was made. With avoidance of all corticosteroids he has been free from urticarial rash for 9 months and has been able to stop all medication.

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Alopecia areata is a form of balding whose aetiology is uncertain. Although the dermal papilla in the hair bulb regulates the follicle and may play a part in the pathogenesis of alopecia areata, its ultrastructure has not been well described. As clinically normal, i.e. non-balding, follicles from alopecia areata scalps show abnormalities at the light microscope level, it would be expected that they should exhibit the earliest pathological changes involved in the dysfunction of the follicle. This study was designed to investigate the ultrastructure of normal human scalp follicular dermal papillae and to see if changes occurred in the ultrastructure of dermal papillae from either lesional or non-balding regions of alopecia areata. Normal dermal papillae contained well formed fibroblast-like cells with large, oval nuclei and well-developed endoplasmic reticulum; the cells were separated from each other by extracellular matrix containing small pieces of collagen and basal lamina-like material. Dermal papillae from both clinically normal and lesional alopecia areata follicles were less well organized and the dermal papilla cells exhibited signs of cell injury and contained abnormal amounts of pigment; an increased concentration of fibrous material in the extracellular matrix and thickening of the dermal papilla-epithelial junction were also seen. Follicles from lesional areas showed more pronounced changes than clinically normal ones. Ultrastructural abnormalities in the dermal papillae of clinically normal scalp follicles support the study of these follicles as a prime research target. The changes detected suggest that dermal papilla cells in alopecia areata would be less able to synthesize regulatory factors and that these may have more difficulty crossing into the epithelial compartment. They are consistent with an early pathological role for the dermal papilla in alopecia areata, but do not distinguish whether this is a primary aetiological role or a secondary response to an insult elsewhere in the follicle.

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A retrospective analysis of patients receiving isotretinoin for acne was performed, in order to determine the necessity for routine testing of lipid profiles and liver function tests during therapy. Data were analysed from 209 individuals, 113 (69 males, 44 females) of whom had been treated with 1 mg/kg/day, and 96 (67 males, 29 females) with 0.5 mg/kg/day. There were no significant changes in any of the tests of liver function. There were significant elevations in both plasma cholesterol and triglycerides at 8 and 16 weeks (P < 0.01) for both dose schedules, which were significant in both male and female subjects (P < 0.001). All the individuals with elevated cholesterol (> 6.5 mmol/l) at 16 weeks had elevated cholesterol at the onset of therapy. Triglyceride concentrations were elevated at 8 weeks, but there was no further increase thereafter. It was not possible to predict which subjects would become hypertriglyceridaemic from pretreatment lipid estimations. In conclusion, there appears to be little evidence to support the previously recommended regular biochemical monitoring of liver function and lipid profiles in patients who are treated with isotretinoin for 16 weeks. It would appear prudent to ensure that there is neither liver disease nor hyperlipidaemia prior to the onset of therapy, and to determine the triglyceride response to therapy on one occasion after 4 weeks' treatment. This change in patient management should result in considerable savings both in patient time and in blood collection and analysis.

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