7th June 2025

Diagnosis

History and examination

• Careful history regarding onset of symptoms (e.g. infancy or childhood), a positive family history of parents’ consanguinity may support the diagnosis
• Examination should include the entire skin surface, nails, hair and mucous membranes. E.g. diffuse/focal/punctate/striate
  • Distribution:
    • Presence or absence of extension to the dorsal area of palms and soles, around the digits
  • Morphology:
    • Presence of hyperkeratosis which presents as waxy and compact areas with fissures associated with erythema and desquamation
  • Extracutaneous findings (e.g. ocular keratitis, hearing loss, cardiac abnormalities and internal malignancies)
• Histopathology:
  • Mainly shows hyperkeratosis and acanthosis. The presence of epidermolysis is important to note as it differentiates epidermolytic-PPK from non-epidermolytic-PPK Image Source: Wikimedia Commons (2017). Palmoplanta Keratoderma, Licensed under a creative commons licence. Available for free at: https://en.wikipedia.org/wiki/Palmoplantar_keratoderma (Accessed 22 May 2025).