An in vivo model of postinflammatory hyperpigmentation and erythema: clinical, colorimetric and molecular characteristics.

BACKGROUND: Postinflammatory hyperpigmentation (PIH) is a common, acquired pigmentary disorder of the skin associated with significant quality-of-life impairment, especially in individuals with skin of colour. Current treatment for PIH is limited, largely due to a poor understanding of disease pathogenesis and the lack of a representative disease model. OBJECTIVES: This study is intended to further develop, update and validate our previously designed in vivo model of acne-induced PIH/postinflammatory erythema (PIE) using different concentrations of trichloroacetic acid (TCA), a medium-depth chemical peel. METHODS: Twenty-nine patients with skin types II-VI and clinician-confirmed presence of two or more truncal acne pustules and PIH/PIE were included. On the basis of Investigator's Global Assessment (IGA), clinical polarized photography (CPP), colorimetry and Skindex, we experimentally determined an optimum TCA concentration and assessed our model's ability to exhibit a dose-response relationship between degree of inciting insult and severity of resulting pigmentation. We also performed differential microRNA profiling and pathway analysis to explore the potential of microRNAs as molecular adjuncts to our model. RESULTS: Application of TCA 30% produced lesions indistinguishable from acne-induced PIH and PIE lesions on the basis of colorimetry data without causing epidermal necrosis. Application of progressively increasing TCA doses from 20% to 30% resulted in concentration-dependent increases in CPP, IGA and colorimetry scores at all timepoints during the study. miRNA-31 and miRNA-23b may play a role in PIH pathogenesis, although further validation is required. CONCLUSIONS: Our TCA-based in vivo model, using TCA concentrations between 20% and 30% with an optimum of 30%, enables the quantitative assessment of the pigmentary response to varying degrees of cutaneous inflammation in a fashion that mirrors natural acne-induced PIH and PIE.

Assessment of inter-rater reliability of clinical hidradenitis suppurativa outcome measures using ultrasonography.

BACKGROUND: Hidradenitis suppurativa (HS) staging and severity is typically based upon physical examination findings, which can result in misclassification of severity based on subclinical disease activity and significant variation between healthcare providers. Ultrasonography (US) is an objective tool to help evaluate subclinical disease and to more accurately classify disease severity. AIM: To evaluate inter-rater reliability in HS disease severity assessment using clinical and US techniques. METHODS: In total, 20 subjects underwent clinical evaluation of HS, independently by two physicians, using clinical outcome measures, including Hurley, Sartorius, HS Physician Global Assessment (HS-PGA) and Hidradenitis Suppurativa Clinical Response (HiSCR). US was subsequently performed, and clinical assessments were repeated. Intraclass correlation coefficients (ICC) were obtained to evaluate inter-rater agreement of each outcome measure before and after US. RESULTS: Pre-US to post-US improvement in ICC was seen with the Sartorius, HiSCR nodule and abscess count, and the HiSCR draining fistula count. The scores went from having 'good' rater agreement for Sartorius and HiSCR nodule and abscess count, to 'poor' rater agreement for HiSCR draining fistula count, to 'excellent' rater agreement among these scores. CONCLUSION: US improved inter-rater agreement and should be used in conjunction with physical examination findings to evaluate disease severity to ensure uniform staging of HS.

International Initiative for Outcomes (INFO) for vitiligo: workshops with patients with vitiligo on repigmentation.

BACKGROUND: There is no cure or firm clinical recommendations for the treatment of vitiligo. One of the main issues is the heterogeneity of outcome measures used in randomized controlled trials for vitiligo. OBJECTIVES: To define successful repigmentation from the patients' point of view and to propose how and when repigmentation should be evaluated in clinical trials in vitiligo. METHODS: We conducted three workshops with patients with vitiligo and their parents or caregivers. Workshop 1 was held at World Vitiligo Day (Detroit, MI), workshop 2 at the University of Texas Southwestern Medical Center and workshop 3 at the Vitiligo and Pigmentation Institute of Southern California, University of California. RESULTS: Seventy-three participants were recruited. Consensus on the following questions was achieved unanimously: (i) the definition of 'successful repigmentation' was 80-100% of repigmentation of a target lesion and (ii) both an objective and a subjective scale to measure repigmentation should be used. CONCLUSIONS: This was the largest patients' outcomes workshop. We followed the guidance from the CSG-COUSIN and the Vitiligo Global Issues Consensus Group. Our recommendations to use percentage of repigmentation quartiles (0-25%, 26-50%, 51-79%, 80-100%) and the Vitiligo Noticeability Scale are based on the best available current evidence. A limitation of the research is that the workshops were conducted only in the U.S.A., due to pre-existing organisational support and the availability of funding.