EczemaPred: A computational framework for personalised prediction of eczema severity dynamics.

BACKGROUND: Atopic dermatitis (AD) is a chronic inflammatory skin disease leading to substantial quality of life impairment with heterogeneous treatment responses. People with AD would benefit from personalised treatment strategies, whose design requires predicting how AD severity evolves for each individual. OBJECTIVE: This study aims to develop a computational framework for personalised prediction of AD severity dynamics. METHODS: We introduced EczemaPred, a computational framework to predict patient-dependent dynamic evolution of AD severity using Bayesian state-space models that describe latent dynamics of AD severity items and how they are measured. We used EczemaPred to predict the dynamic evolution of validated patient-oriented scoring atopic dermatitis (PO-SCORAD) by combining predictions from the models for the nine severity items of PO-SCORAD (six intensity signs, extent of eczema, and two subjective symptoms). We validated this approach using longitudinal data from two independent studies: a published clinical study in which PO-SCORAD was measured twice weekly for 347 AD patients over 17 weeks, and another one in which PO-SCORAD was recorded daily by 16 AD patients for 12 weeks. RESULTS: EczemaPred achieved good performance for personalised predictions of PO-SCORAD and its severity items daily to weekly. EczemaPred outperformed standard time-series forecasting models such as a mixed effect autoregressive model. The uncertainty in predicting PO-SCORAD was mainly attributed to that in predicting intensity signs (75% of the overall uncertainty). CONCLUSIONS: EczemaPred serves as a computational framework to make a personalised prediction of AD severity dynamics relevant to clinical practice. EczemaPred is available as an R package.

Performance characteristics of the VIDAS® 25-OH Vitamin D Total assay - comparison with four immunoassays and two liquid chromatography-tandem mass spectrometry methods in a multicentric study.

BACKGROUND: The study was conducted to evaluate the analytical and clinical performance of the VIDAS® 25-OH Vitamin D Total assay. The clinical performance of the assay was compared with four other immunoassays against the results of two different liquid chromatography/mass spectrometry methods (LC-MS/MS) standardized to NIST reference materials. METHODS: VIDAS® 25-OH Vitamin D Total assay precision, linearity, detection limits and sample matrix comparison were assessed following CLSI guidelines. For method comparison, a total of 150 serum samples ranging from 7 to 92 ng/mL were analyzed by all the methods. Correlation was studied using Passing-Bablok regression and Bland-Altman analysis. The concordance correlation coefficient (CCC) was calculated to evaluate agreement between immunoassays and the reference LC-MS/MS method. In addition, samples containing endogenous 25(OH)D2 were used to assess each immunoassay's ability to detect this analyte. Pregnancy and hemodialysis samples were used to the study the effect of vitamin D binding protein (DBP) concentration over VIDAS® assay performance. RESULTS: The VIDAS® 25-OH Vitamin D Total assay showed excellent correlation to the LC-MS/MS results (y=1.01x+0.22 ng/mL, r=0.93), as obtained from two different sites and distinct LC-MS/MS methods. The limit of quantification was determined at 8.1 ng/mL. Cross-reactivity for 25(OH)D2 was over 80%. At concentrations of 10.5, 26 and 65.1 ng/mL, within-run CVs were 7.9%, 3.6% and 1.7%, while total CVs (between runs, calibrations, lots and instruments) were 16.0%, 4.5% and 2.8%. The VIDAS® performance was not influenced by altered DBP levels, though under-recovery of 25(OH)D as compared to LC-MS/MS was observed for hemodialysis samples. CONCLUSIONS: The VIDAS® 25-OH Vitamin D Total assay is therefore considered suitable for assessment of vitamin D status in clinical routine.

A new ten-item questionnaire for assessing sensitive skin: the Sensitive Scale-10.

Sensitive skin is common but until now there has been no scale for measuring its severity. The Sensitive Scale is a new scale with a 14-item and a 10-item version that was tested in 11 countries in different languages on 2,966 participants. The aim of this study was to validate the pertinence of using the Sensitive Scale to measure the severity of sensitive skin. The internal consistency was high. Correlations with the dry skin type, higher age, female gender, fair phototypes and Dermatology Life Quality Index were found. Using the 10-item version appeared to be preferable because it was quicker and easier to complete, with the same internal consistency and the 4 items that were excluded were very rarely observed in patients. The mean initial scores were around 44/140 and 37/100. The use of a cream for sensitive skin showed the pertinence of the scale before and after treatment.

Retinaldehyde/hyaluronic acid fragments: a synergistic association for the management of skin aging.

BACKGROUND: Retinaldehyde (RAL) was proven effective in treating photodamaged skin. Topical treatments with specific intermediate-size hyaluronate fragments (HAFi, 50-400 kDa) have been shown to stimulate keratinocytes proliferation and epidermal hyperplasia. The aim of this open, multicentric, international study was to assess the efficacy of the combination RAL-HAFi in the correction of skin photoaging. PATIENTS/METHODS: Either RAL 0.05%-HAFi 0.5% (Eluage® cream; group 1) or RAL 0.05%-HAFi 1% (Eluage® antiwrinkle concentrate; group 2) or both products (group 3) were applied daily to the 1462 subjects during 90 days. Overall photoaging severity was evaluated in the three groups by the dermatologists at D0, D30, and D90 based on the Larnier's scale. Wrinkles and/or furrows and clinical signs of aging were evaluated using a 4-point scale. The skin microrelief of the crow's feet, evaluated by optical profilometry, was performed in subjects from group 3. RESULTS: The 3-month application significantly improved overall photoaging through decrease of the Larnier's score in the three groups (P<0.001). At D90, significant improvement of wrinkles was shown in groups 2 and 3 [forehead wrinkles (-19% and -10%, respectively, P<0.001), nasolabial folds (-20% and -16%, P<0.001), crow's feet (-27% in the two groups, P<0.001), and perioral wrinkles (-34% and -23%, P<0.001)]. Clinical signs of photoaging on the entire face improved significantly in groups 1 and 3 [elasticity (-32% and -33%, respectively, P<0.001), hyperpigmentation (-34% and -31%, P<0.001), and ptosis (-18% and -22%; P<0.001)]. Results were confirmed using an optical profilometry technique. Products were very well tolerated. CONCLUSION: This clinical study showed the efficacy and value of the RAL-HAFi combination in the management of aging skin in a large cohort of patients.

Protection afforded by sunscreens containing inorganic sunscreening agents against blue light sensitivity induced by aminolevulinic acid.

BACKGROUND: Application of aminolevulinic acid (ALA) for photodynamic therapy induces significant sensitivity to visible light. OBJECTIVE: To determine whether sunscreens containing inorganic agents are effective against sensitivity to blue light induced by ALA application. METHODS & MATERIALS: Twenty subjects received application of ALA on the arm. Thirty minutes before blue light exposure, two sun protection factor 50 inorganic-based sunscreens containing iron oxide 3.2% and 0.2% were applied on separate areas where ALA was applied; a third area received no sunscreen. Small areas of skin were exposed to increasing fluences of blue light 3 or 18 hours later, and the minimal phototoxic dose (MPD) was noted. RESULTS: Three hours after ALA application MPD was 29.2 and 22.6 J/cm(2) for skin protected with sunscreen containing iron oxide 3.2% and 0.2%, respectively, and 10.6 J/cm(2) for unprotected skin (p=.003 and .0497 respectively). At 18 hours after ALA application, MPD for sunscreen containing iron oxide 3.2% was 5.78, compared with 0.33 for unprotected skin (p<.001) with a blue light protection factor of 21. CONCLUSION: The sunscreen containing iron oxide 3.2% afforded significant protection against blue light sensitivity induced by ALA application.

Comparative benefit of two thermal spring waters after photodynamic therapy procedure.

INTRODUCTION: Photodynamic therapy (PDT) is commonly used to treat actinic keratoses, superficial cutaneous carcinoma, photodamage, and/or acne. The aim of this study was to compare the usefulness of Avène thermal spring water (ATSW), a low mineral content spring water, to a high mineral content spring water. We evaluated post-PDT clinical symptoms and findings when used as an adjunctive therapy in postprocedure skin care. METHODS: A double-blind monocentric comparative study was conducted on 25 patients suffering from either vulgaris acne or photodamage with or without actinic keratoses. The patients were treated with 5-aminolevulinic acid (5-ALA) activated with an intense pulsed light and/or blue light source. Patients were randomized so that 12 patients treated their faces with ATSW and 13 were treated with a comparative water spray. Clinical signs were evaluated by the investigator at day 0, before and 15 min after the first spraying, at days 2, 4, and 7, and each day from day 0 to day 6 by patients. Clinical signs (erythema, stinging, pruritus, pain, and tightening) were evaluated by the use of a 4-point grading scale. RESULTS: The intragroup analysis showed that pain was significantly reduced by ATSW spraying at days 2, 4, and 7. The evaluation by patients showed that only ATSW alleviates pain from day 3 to day 6. The between-group analysis revealed that pruritus was significantly reduced by ATSW at day 7. Erythema, stinging, and tightening were not significantly reduced by both waters. Patients wished to continue using ATSW in 83% of cases. CONCLUSION: This comparative clinical trial demonstrates that ATSW, a low mineral content spring water, can be useful after ALA-PDT in reducing postprocedure cutaneous inflammation and patient discomfort better than a high mineral content spring water.