Juvenile plantar dermatosis
Salient features
·
Dry, scaly, glazed and fissured plantar surface of the forefoot
·
Prepubertal children are affected
·
Association with atopy and exogenous factors
Introduction
This condition is characterized by shiny, dry, fissured
dermatitis of the plantar surface of the forefoot that occurs primarily (but
not exclusively) in children with an atopic diathesis.
Epidemiology
It
occurs mainly in prepubertal children, aged 3–14 years (when shoes are worn for
longer periods of time), and is only rarely seen in adults. There is seasonal
variation (worsening during the winter) and boys are affected slightly more
often than girls.
Pathogenesis
An
atopic disposition is clearly a risk factor, but exogenous factors play an
equally important roleincluding plastic- and rubber-constructed sports shoeswhich are made of impermeable ( non-porous synthetic)
materials, which youngsters often wear all day long. The humid environment
leads to hydration of the horny layer, which is then much less resistant to
wear and tear. It is rubbed off by friction, leading to a characteristic glazed
and thinned appearance of the skin. As involved areas become xerotic, cracks
are formed. Many of the affected children are keen on dancing or sports, and
this suggests that friction may be playing some part. The inherently dry skin
of atopic individuals may be a predisposing factor. Adults have a much thicker
horny layer of their plantar skin and are thus less at risk of developing the
condition.
Clinical
features
The balls of the feet and the toe
pads exhibit strikingly symmetrical changes: fairly well demarcated shiny,
‘glazed’, reddish, tender, dry lesions with some scaling, and often with
painful cracks and fissures. The dorsa of the feet, the toe clefts and the non‐weight‐bearing instep are typically spared. Similar lesions may be
found on the hands, resulting in tender, shiny, fissured palms or fingertips.
This is more likely in atopic subjects.
Most
cases will clear spontaneously during childhood or adolescence, but the
condition may persist into adulthood.
Differential diagnosis
The diagnosis is clinical. Juvenile plantar dermatosis needs to be distinguished
from footwear allergic contact dermatitis to chemicals contained in leather (e.g. chromates,
dyes) or rubber. However, the latter is rare in children and, if present, often
involves the dorsa of the feet as well. Tinea pedis is
equally uncommon in children, and the interdigital spaces are usually
predominantly affected. Patch testing and KOH preparations may help in
establishing the diagnosis.
|
DIFFERENTIAL DIAGNOSIS OF
DERMATITIS OF THE FOOT |
|
Allergic contact dermatitis
(footwear dermatitis) |
|
·
Dermatitis of the dorsal aspects of the
feet and toes (allergen contained in the “top” of the shoes) ·
Dermatitis of the weight bearing areas of
the soles (allergens contained in the sole of the shoes) ·
Most common allergens: dichromate, rubber
accelerators, colophony, dyes, formaldehyde resins; also consider topical
antibiotics, e.g. bacitracin ·
Association with atopy and hyperhidrosis ·
Distinguish from sock and stocking
dermatitis where lesions extend more proximally (popliteal area, thighs) –
most common allergen is azo dyes |
|
Tylosis |
|
·
Mechanically induced hyperkeratosis,
dryness, and fissuring ·
Predilection sites: heels and weight bearing
areas of the soles ·
In middle-aged to elderly individuals ·
Associated with obesity and hyperhidrosis |
|
Acquired plantar keratoderma
(keratoderma climactericum) |
|
·
Same as tylosis but more intense ·
Typically occurs in women over the age of
45 years, but may also be seen in men ·
Similar lesions may appear on palms |
|
Tineapedis (athlete’s foot) |
|
·
Dermatophyte infections of the plantar skin
are usually accompanied by involvement of the interdigital spaces as well as
lateral aspects of the foot ·
Often symmetric, accompanied by
onychomycosis ·
Lesions on the lateral and dorsal aspects
of the feet have well-demarcated circinate borders ·
Occasionally vesicular variant |
|
Psoriasis |
|
·
Well-circumscribed plaques or diffuse
erythema with thick adherent scales, dryness, and fissuring ·
Psoriatic plaques found elsewhere on the
body ·
Nail involvement, e.g. pitting and oil-drop
changes |
|
Recurrent focal palmar and
plantar peeling |
|
·
Probably represents a mild form of
dyshidrosis ·
Dry, circinate, thin scales of palms and
soles ·
Vesicles are absent |
|
Pustulosis of the palms and
soles |
|
·
A neutrophilic dermatosis, possibly related
to pustular psoriasis ·
Chronic course with crops of non-pruritic,
short-lived, superficial pustules, particularly of the instep ·
Yellow–brown macules admixed with pustules |
|
Sézary syndrome |
|
·
Palms and soles are tender and exhibit
scaling, which can be quite thick ·
Associated with hypertrophic
onychodystrophy and erythroderma |
Juvenile plantar dermatosis is a chronic but self-limiting
condition. Patients should be advised to avoid wearing impermeable socks and
shoes and use 100% cotton socks, and
leather shoes or sandals. A variety of topical preparations may help, including
urea preparations, white soft paraffin, and tar or tacrolimus ointment. When
shoes are removed, socks, if damp, should also be removed and replaced by dry
socks.
Therapeutic ladder
First line
·
Change to leather footwear and
cotton socks/open sandals
Second line
·
Emollients, including urea‐containing preparations
Third line
·
Tar/tacrolimus ointment
