A not-so-frequent cause of acquired palmoplantar keratoderma

Dermatological impact of a general disease
Paediatric dermatology

Dr. Emmanuelle Bourrat

Saint-Louis Hospital

The clinical case
Now it's your turn!
Co-prescription and advice

Clinical case presentation

This 13-year-old boy, with no previous history, had been suffering from pruritic plantar lesions on one side and then on both sides for several weeks. A diagnosis of warts was made by a podiatrist, then a dermatologist suggested incipient erythema multiforme.

Application of a potent topical corticosteroid did not prevent progression of the dermatosis to almost diffuse plantar keratoderma associated with more characteristic distant lesions.

These were ring-shaped papules or infiltrated macules, erythematous, in places scaly, on the ankles, wrists and lumbar region. There was no involvement of mucous membranes, nails, face or scalp. A wrist papule was biopsied.

Your turn

What is your diagnosis?

Select 1 answer(s) from the following choices:

Palmoplantar psoriasis

Dermatophytes

Papillon-Lefèvre syndrome

Palmoplantar lichen planus

Wrong answer!

Good answer!

Selected diagnosis

Histology is typical of lichen planus: involvement of the dermoepidermal junction with focal necrosis, slightly thickened orthokeratotic stratum corneum, and a superficial dermis with a band-like lymphocytic infiltrate, nibbling at the junction.

Lichen planus is a classic but rare cause of acquired palmoplantar keratoderma. Diagnosis is relatively easy when there are other more typical cutaneous localizations, as the latter allow easy histological confirmation, which is not always the case when biopsies are taken from the palms or soles.

Palmoplantar lichen planus keratoderma may be punctate or focal (infiltrated macules, sometimes confluent), and much more rarely diffuse. Its functional impact is often significant (pruritus, pain).

Explanation of wrong answers

Palmoplantar psoriasis frequently affects the palms and soles of children in the form of focal or diffuse, often fissured and painful palmoplantar keratoderma (PPK). Neither the topography nor the elementary lesion of the distant involvement is that of psoriasis.
Dermatophytosis must be systematically suspected in the presence of keratoderma, especially on the plantar surface with an asymmetrical onset. Negative mycological sampling and remote involvement rule out this diagnosis.
Papillon-Lefèvre syndrome is an autosomal recessive genetic palmoplantar keratoderma characterized by psoriasiform palmoplantar keratoderma with a postnatal onset, systematically associated with dental alveolitis leading to permanent loss of all teeth.

Treatment

Treatment with very potent topical corticosteroids (with occlusion for plantar keratoderma) leads to progressive regression of inflammatory lesions, disappearance of functional signs and persistence of residual pigmented macules. Remission continues when corticosteroids are discontinued.

Therapeutic management of palmoplantar lichen does not differ from that of lichen outside the palms and soles, with topical corticosteroid therapy as the first-line treatment, which may be followed by oral acitretin or systemic corticosteroid therapy in the event of failure.

Message from the expert

Unlike psoriasis, palmoplantar lichen planus is a very rare cause of palmoplantar keratoderma in children.

References:

^{Almodovar-Real A et al Palmoplantar hyperkeratotic lesions: a rare presentation of lichen planus.}^{Dermatol Online J. 2015 Mar 15;21(5):13030/qt50b5j4g0}