Dyshidrosis

Dyshidrosis is a type of dermatitis that is characterized by itchy blisters on the palms of the hands and bottoms of the feet. Blisters are generally one to two millimeters in size and heal over three weeks. However, they often recur. Redness is not usually present. Repeated attacks may result in fissures and skin thickening.
The cause is unknown. Triggers may include allergens, physical or mental stress, frequent hand washing, or metals. Diagnosis is typically based on what it looks like and the symptoms. Allergy testing and culture may be done to rule out other problems. Other conditions that produce similar symptoms include pustular psoriasis and scabies.
Avoiding triggers may be useful, as may a barrier cream. Treatment is generally with steroid cream. High strength steroid creams may be required for the first week or two. Antihistamines may be used to help with the itch. If this is not effective steroid pills, tacrolimus, or psoralen plus ultraviolet A (PUVA) may be tried.
About 1 in 2,000 people are affected in Sweden. Males and females appear to be affected equally. It explains about one in five cases of hand dermatitis. The first description was in 1873. The name comes from the word "dyshidrotic", meaning "difficult sweating", as problems with sweating was once believed to be the cause.
Signs and symptoms.
Dyshidrosis has been described as having the following characteristics:
Causes.
The exact causes of dyshidrosis are unknown. Food allergens may be involved in certain cases. Cases studies have implicated a wide range of foods including tuna, tomato, pineapple, chocolate, coffee, and spices among others. A number of studies have implicated balsam of Peru. A 2013 study found that dyshydrosis on the hands increased among those allergic to house dust mites, following inhalation of house dust mite allergen.
Id reaction and irritant contact dermatitis are possible causes.
Diagnosis.
Dyshidrosis is diagnosed clinically, by gathering a patient's history and making careful observations (see signs and symptoms section). Severity of symptoms can also be assessed using the dyshidrotic eczema area and severity index (DASI). The DASI has been designed for clinical trials and is not typically used in practice.
Treatment.
There are many treatments available for dyshidrosis. However, few of them have been developed or tested specifically on the condition.
Epidemiology.
About 1 in 2,000 people are affected in Sweden. Males and females appear to be affected equally.
Synonyms.
Dyshidrosis is also known as pompholyx, a term originating from the Greek word for "bubble".