An innovative Fuller's earth-based film-forming formulation for skin decontamination, through removal and entrapment of an organophosphorus compound, paraoxon-ethyl

Organophosphorus compounds (OPs), such as VX, pose a significant threat due to their neurotoxic and hazardous properties. Skin decontamination is essential to avoid irreversible effects. Fuller's earth (FE), a phyllosilicate conventionally employed in powder form, has demonstrated decontamination capacity against OPs. The aim of this study was to develop a formulation that forms a film on the skin, with a significant OP removal capacity (>95 %) coupled with sequestration capabilities, favorable drying time and mechanical properties to allow for easy application and removal, particularly in emergency context. Various formulations were prepared using different concentrations of polyvinyl alcohol (PVA), FE and surfactants. Their removal and sequestration capacity was tested using paraoxon-ethyl (POX), a chemical that simulates the behavior of VX. Formulations with removal capacity levels surpassing 95 % were mechanically characterized and cell viability assays were performed on Normal Human Dermal Fibroblast (NHDF). The four most promising formulations were used to assess decontamination efficacy on pig ear skin explants. These formulations showed decontamination levels ranging from 84.4 ± 4.7 % to 96.5 ± 1.3 %, which is equivalent to current decontamination methods. These results suggest that this technology could be a novel and effective tool for skin decontamination following exposure to OPs.

Aqueous suspensions of Fuller's earth potentiate the adsorption capacities of paraoxon and improve skin decontamination properties

Fuller's earth (FE) is a phyllosilicate used as a powder for household or skin decontamination due to its adsorbent properties. Recent studies have shown that water suspensions exhibit similar adsorbent capacities. FE is heterogeneous due to its composition of elementary clay aggregates and heavy metal particles. Here, FE toxicity was assessed in vitro on skin cells and in vivo on Danio rerio embryos. Among the suspensions tested (5%, 9.1% and 15% w/w), only the highest one shows weak toxicity. Suspensions were tested for ex vivo dermal decontamination into pig ear skin and human abdominal skin using diffusion cells and paraoxon as organophosphorus contaminant. After 24 h of diffusion, no difference was observed in the paraoxon concentration in the receptor compartment whether the decontamination was carried out with FE in powder or in suspension form. In presence of FE suspensions, we observed the disappearance of paraoxon from the stratum corneum, the reservoir compartment, independently of the suspensions' concentration. We suggest that water potentiates the absorbing capacities of FE powder by intercalating between clay lamellas leading to the appearance of new adsorption zones and swelling. These data support the use of FE aqueous suspensions as a safe tool for organophosphorus skin decontamination.

Clinical and demographic features of hidradenitis suppurativa: a multicentre study of 1221 patients with an analysis of risk factors associated with disease severity

BACKGROUND

Hidradenitis suppurativa (HS) is a chronic, relapsing and debilitating inflammatory disease associated with profound morbidity.

AIM

In this multicentre study, we investigated the demographic and clinical features of HS, and determined risk factors of disease severity.

METHODS

In total, 1221 patients diagnosed with HS from 29 centres were enrolled, and the medical records of each patient were reviewed.

RESULTS

The mean age of disease onset was 26.2 ± 10.4 years, and almost 70% (n = 849) of patients were current or former smokers. Mean disease duration was 8.9 ± 8.4 years with a delay in diagnosis of 5.8 ± 3.91 years. Just over a fifth (21%; n = 256) of patients had a family history of HS. The axillary, genital and neck regions were more frequently affected in men than in women, and the inframammary region was more frequently affected in women than in men (P < 0.05 for all). Acne (40.8%), pilonidal sinus (23.6%) and diabetes mellitus (12.6%) were the most prevalent associated diseases. Of the various therapies used, antibiotics (76.4%) were most common followed by retinoids (41.7%), surgical interventions (32.0%) and biologic agents (15.4%). Logistic regression analysis revealed that the most important determinants of disease severity were male sex (OR = 2.21) and involvement of the genitals (OR = 3.39) and inguinal region (OR = 2.25). More severe disease was associated with comorbidity, longer disease duration, longer diagnosis delay and a higher number of smoking pack-years.

CONCLUSIONS

Our nationwide cohort study found demographic and clinical variation in HS, which may help broaden the understanding of HS and factors associated with disease severity.