Plasma p-tau217 in Alzheimer's disease: Lumipulse and ALZpath SIMOA head-to-head comparison.

Background: Plasma phosphorylated-tau217 (p-tau217) has been shown to be one of the most accurate diagnostic markers for Alzheimer's disease (AD). No studies have compared the clinical performance of p-tau217 as assessed by the fully automated Lumipulse and SIMOA ALZpath p-tau217. Aim: To evaluate the diagnostic accuracy of Lumipulse and SIMOA plasma p-tau217 assays for AD. Methods: The study included 392 participants, 162 with AD, 70 with other neurodegenerative diseases (NDD) with CSF biomarkers and 160 healthy controls. Plasma p-tau217 levels were measured using the Lumipulse and ALZpath SIMOA assays. The ability of p-tau217 assessed by both techniques to discriminate AD from NDD and controls was investigated using ROC analyses. Results: Both techniques showed high internal consistency of p-tau217 with similar correlation with CSF p-tau181 levels. In head-to-head comparison, Lumipulse and SIMOA showed similar diagnostic accuracy for differentiating AD from NDD (area under the curve [AUC] 0.952, 95%CI 0.927-0.978 vs 0.955, 95%CI 0.928-0.982, respectively) and HC (AUC 0.938, 95%CI 0.910-0.966 and 0.937, 95% CI0.907-0.967 for both assays). Conclusions: This study demonstrated the high precision and diagnostic accuracy of p-tau217 for the clinical diagnosis of Alzheimer's disease using either fully automated or semi-automated techniques.

Testing for myositis specific autoantibodies: Comparison between line blot and immunoprecipitation assays in 57 myositis sera.

OBJECTIVE: To analyze the performance of a line blot assay for the identification of autoantibodies in sera of patients affected by myositis, compared with immunoprecipitation (IP) as gold standard. METHODS: 66 sera of patients with myositis (23 polymyositis, 8 anti-synthetase syndromes, 29 dermatomyositis and 6 overlap syndromes) were tested by commercial LB (Euroimmun, Lubeck, Germany); 57 sera were analyzed also by IP of K562 cell extract radiolabeled with (35)S-methionine. Inter-rater agreement was calculated with Cohen's k coefficient. RESULTS: Myositis-specific antibodies (MSA) were detected in 36/57 sera (63%) by IP and in 39/66 sera (59%) by LB. The most frequent MSA found by LB were anti-Jo1 and anti-Mi2 found in 15% (10/66) of sera, followed by anti-NXP2 and anti-SRP detected in 106% (7/66) of sera. Anti-TIF1gamma and anti-MDA5 were found in 6 (9%) and 5 sera (7.6%), respectively. A good agreement between methods was found only for anti-TIF1γ, anti-MDA5 and anti-NXP-2 antibodies, while a moderate agreement was estimated for anti-Mi2 and anti-EJ. By contrast, a high discordance rate for the detection of anti-Jo1 antibodies was evident (k: 0.3). Multiple positivity for MSA were found in 11/66 (17%) by LB and 0/57 by IP (p: 0001). Comparing the clinical features of these 11 sera, we found total discrepancies between assays in 3 sera (27.3%), a relative discrepancy due to the occurrence of one discordant autoantibody (not confirmed by IP) in 5 cases (45.5%) and a total discrepancy between LB and IP results, but with a relative concordance with clinical features were found in other 3 sera (27.3%). The semiquantitative results do not support the interpretation of the data. CONCLUSIONS: The use of LB assay allowed the detection of new MSA, such as anti-MDA5, anti-MJ and anti-TIF1gamma antibodies, previously not found with routine methods. However, the high prevalence of multiple positivities and the high discondant rate of anti-Jo1 antibodies could create some misinterpretation of the results from the clinical point of view. These data should be confirmed by enlarging the number of myositis cases.

Childhood nail psoriasis: a useful treatment with tazarotene 0.05%.

Nail psoriasis occurs in 7% to 40% of children, with a similar pattern of clinical presentation to that of adults. In 0.6% to 2.3% of the patients nail changes appear as the only sign of the disease, preceding other skin and articular involvement. No pediatric clinical trials are available yet, but considering the successful use of tazarotene for nail dystrophy therapy in adults, we chose this drug to treat a child.

Microabrasion versus microabrasion followed by 15% trichloroacetic acid for treatment of cutaneous hyperpigmentations in adult females.

BACKGROUND: Cutaneous hyperpigmentations are common skin disorders that are often refractory to currently available treatments. OBJECTIVE: To evaluate the efficacy of microabrasion alone or microabrasion with 15% trichloroacetic acid (TCA) for treatment of cutaneous hyperpigmentations. METHODS: Twenty female patients were treated with microabrasion alone every 2 weeks (group 1), and 20 female patients were treated with microabrasion and application of 15% TCA every 3 weeks (group 2). All patients underwent up to eight treatments. The overall duration of treatment ranged from 2 to 4 months. RESULTS: In group 1, a complete remission was observed in 8 of 20 cases (40%), partial remission in 10 of 20 cases (50%), and no remission in 2 of 20 cases (10%). In group 2, a complete remission was observed in 10 of 20 cases (50%), a partial remission in 8 of 20 cases (40%), and no remission in 2 of 20 cases (10%). No unexpected or serious side effects were observed in either group. CONCLUSIONS: Microabrasion alone or microabrasion with 15% TCA is an effective, well-tolerated treatment for cutaneous hyperpigmentations.