Pompholyx (Dyshidrotic Eczema)

Synonyms: dyshidrotic eczema, cheiropompholyx or chiropompholyx, and dyshidrotic dermatitis: (this implies that the condition is related to sweat glands, but this association is unproven).

The name pompholyx comes from the Greek word for bubble.

It accounts of around 5% of cases of eczema of the hand. The usual age of those affected is 20 to 40 but it does affect teenagers and older people. There is a female preponderance of 2:1.

Risk factors

Although the aetiology is unknown there are a number of factors that have been identified as predisposing to outbreaks. It is said that emotional stress can aggravate, but not cause it. Allergic contact dermatitis may be involved, especially in recurrent cases.¹ Allergens such as chromate, neomycin, quinolones, or nickel have been implicated. There is an association with atopy and tinia pedis but both pompholyx and tinea pedis are likely to occur with sweaty feet and causation is not proved.

The condition may be acute, chronic or recurrent.

• The affected areas are the centre of the palms or soles.
• It is usually symmetrical.
• After several hours of itching or burning in the hands, feet or both, the eruption develops. Tiny vesicles, about 1 or 2mm in diameter, erupt first along the lateral aspects of the fingers and then on the palms or soles.
• Palms and soles may be red and wet with perspiration.
• Later in the course there may be unroofed vesicles with inflamed bases, possibly accompanied by peeling or rings of scale or lichenification.
• Transverse furrows can develop on the nail when eruptions occur in the periungual areaor nail matrix.
• Vesicle may break out in waves.
• The vesicles usually persist for 3 or 4 weeks and disappear spontaneously.

• Pustular psoriasis
• Fungal infection.

There are no specific investigations that are indicated.

The condition is self limiting but as it can be intensely itchy, symptomatic treatment may be in order.

• Aluminum subacetate, or Burrow's Solution, is a drying soak that can be used if the lesions ooze.
• Large blisters can be drained under aseptic conditions.
• Antibiotics are only required if secondary infection occurs.
• Strong topical steroids to control itching and cold compresses are the usual first line treatment.
• Second line treatment may be oral steroids.
• Long wave PUVA has been used.²
• Severe cases may be treated with oral methotrexate³ but this is rarely justified.
• Aluminum chloride 20% may help to control sweating.
• A developing treatment is intradermal injection of botulinum toxin.⁴

Secondary bacterial infection may occur. Emotional stress may have aggravated the disease and now the disease aggravates the stress.

Most patients recover spontaneously in 3 to 4 weeks but some have a chronic and unremitting course.