Non-Invasive Imaging to Detect the Effects of Topical N-Butanoyl Glutathione (GSH-C4) and Hyaluronic Acid in Inflammatory Eczematous Dermatitis

Background: Eczematous dermatitis refers to a group of inflammatory skin disorders—including seborrheic, atopic, and contact dermatitis—characterized by epidermal barrier dysfunction and chronic inflammation. Disrupting the itch–scratch cycle and reversing microscopic skin changes are key to improving patient outcomes and quality of life. Aims: This study aimed to assess the clinical and microscopic effects of a topical medical device containing N-butanoyl glutathione (GSH-C4) and hyaluronic acid in patients with inflammatory eczematous dermatitis, combining clinical scores with in vivo confocal and OCT imaging. Methods: A prospective clinical trial enrolled 30 patients with active eczematous lesions. Participants applied a GSH-C4/hyaluronic acid-based product (GSEBA®) for 28 days. Clinical improvement was evaluated at baseline, day 14, and day 28 using the Investigator’s Global Assessment (IGA), a Visual Analog Scale (VAS) for itching, and a self-reported index of disease impact on quality of life (IDL). Microscopic changes were assessed using optical coherence tomography (OCT) and reflectance confocal microscopy (RCM). Results: After 28 days, the mean IGA score improved from 2.48 to 0.18 (p < 0.001), VAS itching score decreased from 4.52 to 0.32 (p < 0.001), and IDL dropped from 4.86 to 0.79 (p < 0.001). RCM analysis showed significant reductions in key inflammatory features such as spongiosis, vesiculation, and inflammatory infiltrate. OCT revealed a significant decrease in vascularization at 150 μm depth, with no change in collagen density. Conclusions: The GSH-C4/hyaluronic acid-based mousse (GSEBA®) demonstrated strong clinical efficacy and excellent tolerability in managing eczematous dermatitis. It effectively reduced both symptoms and microscopic markers of inflammation without compromising dermal structure.