Characterization of a Perturbed Skin Microbiome in Prurigo Nodularis and Lichen Simplex Chronicus

In recent years, evidence is mounting on the critical role of the skin microbiota in a variety of human pathologies (Naik et al., 2020). An improved understanding of the interrelation between the skin microbiota and the nervous system, also known as the skin–brain axis, suggests that the cutaneous microbiome may affect the itch–scratch cycle (Kim and Yosipovitch, 2020). Cutaneous microbes also produce substantial numbers of proteolytic enzymes targeting various host proteins (Rademacher et al., 2022), including protease-activated receptors present on keratinocytes and sensory nerves (Chiu, 2018).