The major psoriasis susceptibility locus PSORS1 is not a risk factor for late-onset psoriasis.

PSORS1 is the major susceptibility locus for psoriasis vulgaris (PV) and lies within an approximately 200 kb segment of the major histocompatibility complex on chromosome 6p21.3. Alleles of candidate genes in this region including human leukocyte antigen (HLA)-C, alpha-helical coiled coil rod (HCR), and corneodesmosin (CDSN) show association with early-onset PV. Late-onset psoriasis (LOP) is defined as a disease with onset after 40 y of age and is typically sporadic. We assessed the role of PSORS1 in genetic susceptibility to LOP. Genotyping for HLA-C alleles and seven single nucleotide polymorphisms (SNP) within the genes HCR and CDSN was performed in LOP (n=145) and normal controls (n=309). Statistical analysis of allelic frequencies included calculation of odds ratio and chi2 comparisons. LOP demonstrated only a weak association to PSORS1 alleles HLA-Cw*6 (p=0.037), CDSN*5 (p=0.041), HCR*WC (p=0.013), and HCR SNP +325 (p=0.038). Patients with age of onset for psoriasis of 50 y or above provided no evidence of association with any of these alleles. These data suggest that the study cohort may include a number of subjects who harbor PSORS1 predisposition to early-onset psoriasis and yet do not present with disease by the age of 40 y. Thus this study demonstrates that PSORS1 is not a major inherited risk factor in the pathogenesis of LOP. These data suggest that the exclusion of LOP subjects from case-control studies will aid further delineation of the PSORS1 locus. Future genome-wide studies will be required to identify loci conferring risk for late-onset disease.

Treating Bowen's disease: a cost-minimization study.

BACKGROUND: In the current economic climate, it is important to justify the cost of treatments used in dermatology, particularly where cheaper alternatives exist. OBJECTIVES: To determine which treatment modality commonly used for Bowen's disease is associated with the lowest cost to the National Health Service. METHODS: A cost-minimization analysis was used to compare the following six treatments for Bowen's disease: cryotherapy, curettage and cautery, excision, laser ablation, photodynamic therapy and 5-fluorouracil. These are all known to have similar recurrence rates. Information regarding use of these treatment modalities was extracted from a literature review. Costs were determined from published data, average wholesale prices of medications, staff salary pay scales and health economics departments. RESULTS: The results show that, if treatment is indeed undertaken, a single lesion of Bowen's disease is most cheaply treated by curettage or excision biopsy under local anaesthetic, and most expensively treated by photodynamic therapy. The usefulness of this information has to be taken in the context of the study design, outcome measurements and base assumptions. CONCLUSIONS: Valid costing studies such as this, in conjunction with evidence of effectiveness and safety, can provide guidance for resource allocation and treatment decisions.

Nail dystrophy due to lichen sclerosus?

Lichen sclerosus (LS) affects anogenital skin alone in 80% of cases. When extragenital disease occurs, it usually affects the trunk, neck, axillae and wrist flexures. Nail involvement with LS is rare. In contrast, lichen planus (LP) commonly affects extragenital skin. Mucosal lesions occur in 50% of cases, affecting the mouth and genitalia. Nail disease in LP is common, and, if severe, can lead to destruction of the nail bed. LS and LP can coexist. We report two cases of LS with nail involvement. In the Case 1 disease was confined to the nail, and nail biopsy confirmed LS. In the Case 2, the nail changes formed part of the widespread genital and extragenital LS, confirmed histologically. We review existing literature on nail disease in LS and discuss the possible aetiology of the nail changes.