[Aquagenic palmoplantar keratoderma during treatment of Langerhans cell histiocytosis]

Aquagenic palmoplantar keratoderma (APPK) is characterised by whitish oedematous papules, sometimes itchy or painful of rapid onset following immersion of the palms and/or soles in water. We report a case that was atypical in terms of the secondary appearance of persistent fine desquamation.

A 6-year-old girl presented with typical APPK, present for three months and characterised by swelling, skin wrinkling, hyperhidrosis and secondary desquamation of the palms and soles, and which occurred after bathing. The patient had been treated with vinblastine, mercaptopurine and oral corticosteroids for Langerhans cell histiocytosis ongoing for six months. Physical examination revealed persistent fine desquamation of the palms and soles, occurring some time after immersion in water. There was no mutation of the CFTR gene. No similar cases could be found in the pharmacovigilance database. Topical therapy with an emollient provided some relief. Symptoms had partially resolved two months after discontinuation of chemotherapy and oral corticosteroids.

Cases of unilateral palmar damage involving unusual sites have been reported. Neither secondary desquamation nor association with Langerhans cell histiocytosis have been described. Hyperhidrosis and association with 1 or 2 CFTR mutations appear to constitute predisposing factors. There are cases of APPK related to anti-inflammatory intake. In view of the clinical course, an iatrogenic origin cannot be excluded in this case.

Persistent fine palmoplantar desquamation may be a manifestation of APPK.