Erythema Nodosum Induced by the Pfizer- BioNTech Vaccine

A 42-year-old man presented with a painful nodular dermatitis with 38.5°C fever and joint pain, which started overnight. The patient had taken the first dose of Pfizer-BioNTech (Comirnaty, INN-COVID-19 mRNA) vaccine 8 days ago. He denied any kind of recent infections, inflammatory conditions, malignancies, or drugs administration.

In vivo transepidermal water loss: Validation of a new multi-sensor open chamber water evaporation system Tewameter TM Hex

BACKGROUND

Instrumentation technology for transepidermal water loss measurements has not been substantially modified since its introduction by Nilsson in 1977. Recent progress in sensor development allowed a new sensor arrangement using a matrix of 30 sensors. Raw measurement values are processed with spatial statistical analysis. We aimed to compare the new, multi-sensor probe (Tewameter TM Hex) with the established Tewameter TM 300 probe and to gain reference data for the new parameters of transepidermal energy loss and water vapor concentration on skin.

MATERIAL AND METHODS

Baseline measurements and repeated measurements on the volar forearm and assessment on eight different anatomical locations were performed on 24 healthy volunteers (both gender) with the TM Hex and the TM 300.

RESULTS

A significant correlation (p < 0.001; R-coefficient = 0.9) between TM Hex and the TM 300 with a low coefficient of variance (CV) 11% for TM Hex and 19% for TM 300, could be assessed. The CV ranged between 7% (right inner upper arm) and 14% (palms). Average transepidermal heat loss ranged from 12 W/m2 on the lower leg to 38.8 W/m2 on the palm.

CONCLUSION

The correlation between TM Hex and TM 300 along with the robustness of the measurements with the TM Hex shows that the new probe for assessment of epidermal barrier function is comparable to the TM 300. In most conditions, TM Hex provides more accurate measurements than TM 300. New parameters open the field to studying skin's water and energy balance.

Acidic skin care promotes cutaneous microbiome recovery and skin physiology in an acute stratum corneum stress model

INTRODUCTION

Skin microbiome and skin physiology are important indicators of the epidermal homeostasis status. Stress models can reveal pathological conditions and modulating effects. Here we investigated the cutaneous microbiome in relation to skin physiology after mild tape stripping (TS) without treatment compared to two cosmetic leave-on lotions (pH 5.5 vs. pH 9.3) in 25 healthy volunteers.

METHODS

The microbiome was analyzed by 16S-rRNA-gene amplicon sequencing and put in relation to the following skin physiology parameter: epidermal barrier function (TEWA-Meter TM300), stratum corneum hydration (Corneometer CM 825), surface pH (pH-Meter) and skin erythema (Mexameter).

RESULTS

TS reduced the alpha diversity with a recovery over 7 days without treatment. Both lotions significantly accelerated the recovery of the alpha-diversity already after 2 days with a slightly higher rate for the acidic lotion. After TS, the relative abundance of Proteobacteria was increased, whereas Actinobacteria were reduced. The relative abundances of typical skin-associated genera were reduced after TS. Taxa compositions returned to normal levels after 7 days in all treatment groups. An accelerated normalization could be observed with both lotions already after two days. A significant difference in skin pH was observed on day2 and day7 with an increased pH for the alkaline lotion. Both lotions induced an increase in stratum corneum hydration.

CONCLUSION

The study proved the suitability of an experimental stress model in the assessment of skin surface microbiome in relation to skin physiology. Stratum corneum hydration increased significantly with both lotions already at day2. Microbiome parameters (alpha-diversity, mean relative taxa, abundance of selected genera) normalized over 2-7 days. The following mechanisms could be responsible for the accelerated normalization of the microbiome: a) optimized hydration during the recovery phase, b) the composition of the lotion c) the induced repair mechanism. Thus, the formulation has a positive effect on the stratum corneum hydration and subsequently on cutaneous microbiome and skin physiology. Furthermore, this has eventually implications in the modulation of exogenous stress-induced epidermal alterations.