7th June 2025

Aetiology

• Hereditary PPK is caused by a mutation in the genes that either code a protein in the keratin
• Can manifest as a sole dermatological disease, i.e. non syndromic or along with extra cutaneous manifestations, i.e. syndromic-i.e. in relation to an inflammatory skin condition (e.g. eczema or psoriasis), systemic inflammatory disease, internal cancers etc.
• Inheritance: 
  • Autosomal dominant, recessive or X linked. 
  • Mitochondrial inheritance has also been reported.

Subtypes

• Diffuse keratoderma
  • Affects the palms and soles
• Focal keratoderma 
  • Mainly involves the pressure areas.
• Punctate-type keratoderma
  • Causes bumps on the palms and soles.