Is Demodex hiding in lichen planopilaris pathogenesis? The trichoscopy-blind zone.

The pathogenic role of commensal Demodex mites in lichen planopilaris remains hypothetical. We propose a multifactorial model where mite lipases and antigens disrupt follicular peroxisome proliferator-activated receptor gamma (PPAR-γ) signalling and trigger a lymphocytic response that may progress to autoimmunity. A therapeutic paradox exists, as immunomodulatory treatments may reduce inflammation but also promote mite proliferation, underscoring the need for controlled trials.