Dyshidrosis

Dyshidrosis
Synonyms	acute vesiculobullous hand eczema,[1] dyshidrotic dermatitis,[2] cheiropompholyx, dyshidrotic eczema, pompholyx, podopompholyx[3]
The characteristic vesicles of dyshidrosis on a finger
Pronunciation	/dɪs.haɪˈdroʊ.sᵻs/[4]
Classification and external resources
Specialty	Dermatology
ICD-10	L30.1
ICD-9-CM	705.81
DiseasesDB	10373
MedlinePlus	000832
eMedicine	derm/110 ped/1867
Patient UK	Dyshidrosis
MeSH	D011146

Dyshidrosis, is a type of dermatitis, that is characterized by itchy blisters on the palms of the hands and bottoms of the feet.^[5] The blister are generally one to two millimeters in size and heal over three weeks.^[6][7] Redness is not usually present.^[6] They; however, often recur.^[7] Repeated attacks may result in fissures and skin thickening.^[6]

The cause is unknown. Trigger 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.^[7] Other conditions that produce similar symptoms include pustular psoriasis and scabies.^[6]

Avoiding triggers may be useful as may a barrier cream.^[6] Treatment is generally with steroid cream.^[7] High strength steroid creams may be required for the first week or two.^[6] Antihistamines may be used to help with the itch.^[7] If this is not effective steroid pills, tacrolimus, or psoralen plus ultraviolet A (PUVA) may be tried.^[6][7]

About 1 in 2,000 people are affected in Sweden. Males and females appear to be affected equally. 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.^[6]

Signs and symptoms

Small blisters with the following characteristics:

• Blisters are very small (3 mm or less in diameter). They appear on the tips and sides of the fingers, toes, palms, and soles.
• Blisters are opaque and deep-seated; they are either flush with the skin or slightly elevated and do not break easily. Eventually, small blisters come together and form large blisters.
• Blisters may itch, cause pain, or produce no symptoms at all. They worsen after contact with soap, water, or irritating substances.
• Scratching blisters breaks them, releasing the fluid inside, causing the skin to crust and eventually crack. This cracking is painful as well as unsightly and often takes weeks, or even months to heal. The skin is dry and scaly during this period.
• Fluid from the blisters is serum that accumulates between the irritated skin cells. It is not sweat as was previously thought.
• In some cases, as the blistering takes place in the palms or finger, lymph node swelling may accompany the outbreak. This is characterised by tingling feeling in the forearm and bumps present in the arm pits.
• Nails on affected fingers, or toes, may take on a pitted appearance.

• 
  Advanced stage of dyshidrosis on the fingers
• 
  Palmar dyshidrosis
• 
  Advanced stage of palmar dyshidrosis on the palm showing cracked and peeling skin
• 
  Advanced stage of dyshidrosis on the foot.
• 
  Rim of scale on the palmar surface of the thumb from a resolving dyshidrotic flare

Causes

The exact causes of dyshidrosis are unknown. In 2013, a randomized, double-blind, placebo-controlled cross-over study by the University Medical Center Groningen reported that dyshydrosis outbreaks on the hands increased significantly among those allergic to house dust mites, following inhalation of house dust mite allergen.^[8]

Food allergens may be involved in certain cases.^[9] Cases studies have implicated a wide range of foods including tuna, tomato, pineapple, chocolate, coffee, and spices among others.^[9] A number of studies have implicated balsam of Peru.^[9]

Treatment

There are many treatments available for dyshidrosis. However, few of them have been developed or tested specifically on the condition.

• Topical steroids^[10] - while useful, can be dangerous long-term due to the skin-thinning side-effects, which are particularly troublesome in the context of hand dyshidrosis, due to the amount of toxins and bacteria the hands typically come in contact with.
• Potassium permanganate dilute solution soaks - also popular, and used to 'dry out' the vesicles,^[11] and kill off superficial Staphylococcus aureus,^[12] but it can also be very painful. Undiluted it may cause significant burning.^[13]
• Dapsone (diamino-diphenyl sulfone), an antibacterial, has been recommended for the treatment of dyshidrosis in some chronic cases.^[14]
• Antihistamines: Fexofenadine up to 180 mg per day.^[15]
• Alitretinoin (9-cis-retinoic acid) has been approved for prescription in the UK. It is specifically used for chronic hand and foot eczema.^[16][17][18] It is made by Basilea of Switzerland (BAL 4079).

See also

• Epidermolysis bullosa - a genetic disorder that causes similar, albeit more severe, symptoms to those of dyshidrosis.
• Dermatitis herpetiformis - a similar condition caused by celiac and often mistaken for dyshidrosis.

References

External links

Wikimedia Commons has media related to Dyshidrosis.

• Images of dyshidrotic eczema at Skinsight
• Pompholyx at DermNet NZ (New Zealand Dermatological Society Incorporated)