Aquagenic keratoderma associated with a mutation of the cystic fibrosis gene.

Reported for the first time in 1996, aquagenic keratoderma is a rare condition which is characterized by edematous flat-topped papules appearing on palmar skin after water immersion. Multiple anecdotal associations have been described but, recently, the association with cystic fibrosis gene mutations (CFTR) has been highlighted. The authors describe an 18 year-old female, with one-month complaints of pruritus and swelling of palmar skin after water immersion. On examination, palmar skin was unremarkable but, 5 minutes after water immersion, multiple whitish papules became apparent. CFTR genotype study showed a F508del mutation in one allele. She had no other symptoms and no relevant family history. Aquagenic keratoderma is probably an under-diagnosed entity that might represent a manifestation of CFTR mutations, making carrier state identification and genetic counseling possible.