Exact pathophysiology of PN is currently
not understood.
Based on the evolving literature, type 2
inflammation may play a role in PN.
Sensitization of nerves to
pruritogens11,a
Upregulation of the receptor
for IL-3112,13
Increased fibroblast proliferation and collagen production,
periostin expression and stimulating profibrotic cytokine TGF-β
production may influence skin remodeling
and nodule formation11,12
Skin barrier dysfunction: inhibition of keratinocyte differentiation
and altered lipid synthesis13
Epidermal differentiation,
inflammatory responses,
and
extracellular
remodeling14
aIn ex-vivo or mouse experiments.
IL, interleukin; PN, prurigo nodularis; QoL, quality of life; TGF, transforming growth factor.
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