What is keratolysis exfoliativa?
Keratolysis exfoliativa is a common skin condition in which there is focal peeling of the palms and less often the soles. It is also known as exfoliative keratolysis, dyshidrosis lamellosa sicca, and focal palmar peeling.
Who gets keratolysis exfoliativa?
Keratolysis exfoliativa generally presents in young active adults. Some individuals have a family history of the disorder.
What is the cause of keratolysis exfoliativa?
The cause of keratolysis exfoliativa is unknown. Microscopy reveals cleavage within the outside horny layer of skin, the stratum corneum. It is thought that for some reason the desmosomes on the corneocytes separate from each other prematurely. No genetic abnormality has been detected to date (2018).
The symptoms are aggravated by exposure to irritants including water, soap, detergents and solvents.
What are the clinical features of keratolysis exfoliativa?
Keratolysis exfoliativa is more common during the summer months in about 50% of affected individuals. It may be more common in those with sweaty palms due to localised hyperhidrosis.
The first sign of keratolysis exfoliativa is one or more superficial air-filled blisters on the fingers or palms. The blisters burst to leave expanding collarettes of scale and circular or oval, tender, erythematous peeled areas. These peeled areas lack a normal barrier function and may become dry and cracked. However, they are not generally itchy.
Sometimes on the ends of the fingers, the split in the skin is deeper, in which case the skin feels hard and numb and takes longer to peel off. There can be multiple layers of peeling skin (lamellae).
Eventually normal skin forms, but frequently exfoliative keratolysis recurs within a few weeks.
How is keratolysis exfoliativa diagnosed?
Keratolysis exfoliativa is diagnosed clinically. Supportive investigations may be undertaken.
- Skin biopsy shows cleavage and partially degraded corneodesmosomes within the stratum corneum.
- Skin scrapings sent for laboratory tests for fungal infections are negative.
- Patch tests evaluating potential contact allergy are negative.
What is the differential diagnosis with keratolysis exfoliativa?
Keratolysis exfoliativa is distinct from the following conditions.
- Various forms of hand dermatitis including contact dermatitis
- Pompholyx, an itchy form of eczema in which there are small fluid-filled blisters.
- Palmoplantar psoriasis, in which there are scaly patches
- Tinea manuum, but scrapings for fungal culture are negative in keratolysis exfoliativa
- Keratolytic winter erythema, a rare inherited condition characterised by red peeling hands and feet
- Palmoplantar keratoderma
- Localised epidermolysis bullosa simplex, in which blistering occurs
- Circumscribed palmar hypokeratosis
What is the treatment for keratolysis exfoliativa?
Keratolysis exfoliativa does not improve with topical steroids, unlike hand dermatitis.
The following may be helpful:
- Protection from irritants
- Emollient hand creams especially those containing urea, lactic acid, or silicone