Dyshidrosis

# Overview
Dyshidrosis, also termed Dyshidrotic Eczema, Pompholyx and Dyshidrotic Dermatitis, is a skin condition that is characterized by small blisters on the hands or feet. It is an acute, chronic, or recurrent dermatosis of the fingers, palms, and soles, characterized by a sudden onset of many deep-seated pruritic, clear vesicles; later, scaling, fissures and lichenification occur.  Recurrence is common and for many can be chronic.   Incidence/Prevalence is said to be 20/100,000 in the USA, however, many cases of eczema are diagnosed as garden-variety atopic eczema without further investigation, so it is possible this figure is misleading.
This condition is not contagious to others, but due to its unsightly nature can cause significant distress in regards to social interactions with others.
The name comes from the word "dyshidrotic," meaning "bad sweating," which was once believed to be the cause.  Sometimes called pompholyx (Greek for "bubble") which is generally reserved for the cases with blisters; in some countries, pompholyx refers to hand dyshidrosis.

# Symptoms
Small blisters with the following characteristics:
- Blisters are very small (1 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.

# Causes
Causes of dyshidrosis are unknown, however, a number of triggers to the condition exist.
- Dyshidrosis has been historically linked to excessive sweating during periods of anxiety, stress, and frustration, however, many cases present that have no history of excessive sweating, and the hypothesis of dyshidrosis as a sweating disorder is largely rejected.  Some patients reject this link to stress, though as a trigger of vesicular eruption it cannot be overlooked, as with other types of eczema.
- Vesicular eruption of the hands may also be caused by a local infection, with fungal infections being the most common. Sunlight is thought to bring on attacks, some patients link outbreaks to prolonged exposure to strong sunlight from late spring through to early autumn. Others have also noted outbreaks occurring in conjunction with exposure to chlorinated pool water or highly treated city tap waters.
- Soaps, detergents, fragrances and contact with fruit juices or fresh meat also can trigger outbreaks of dyshidrosis, as with other types of eczema.
- Systemic nickel allergies may be related.
- Keeping skin damp will trigger or worsen an outbreak.  For this reason, people with dyshidrosis should wear gloves, socks, and shoes made of materials which "breathe well", such as cotton or silk. Certain fabrics may greatly irritate the condition, including wool, nylon and many synthetic fabrics.
- Inherited, not contagious. Often, patients will present with other types of dermatitis, such as seborrheic dermatitis or atopic eczema.  For this reason, among others, dyshidrosis is often dismissed as atopic eczema or contact dermatitis.
- Can be the secondary effect of problems in the gut. Some sufferers claim diet can ease symptoms (relieving internal condition of IBS or intestinal yeast infection).  Also Inflammatory bowel diseases of Ulcerative colitis and Crohn's disease.
- Bandages, plasters or other types of skin-tapes may be irritating to dyshidrosis and should be avoided. As the skin needs to breathe, anything that encourages maceration of the palms should be avoided.  If the 'wounds' are raw enough to warrant covering, pure cotton gloves or gauze should be used. Liquid Band-Aid brand bandage may be tolerated and helpful, refer to the Treatment section, below.
- Latex and vinyl gloves may increase irritation.
- Multiple Chemical Sensitivity
- Allergic reaction to Potassium Dichromate (leather preservative)
- Dyshidrosis can sometimes even be caused by dust mite allergies, with sufferers having to wash and change bedding weekly, sometimes even every 2 days or even every day, to combat symptoms.

# Diagnosis

## Physical Examination

## Skin
- Dyshidrotic eczema. Adapted from Dermatology Atlas.
- Dyshidrotic eczema. Adapted from Dermatology Atlas.
- Dyshidrotic eczema. Adapted from Dermatology Atlas.

# Treatment
There are many treatments available for dyshidrosis, however, few of them have been developed or tested specifically on the condition.
- Topical steroids - 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.
- Nutritional deficiencies may be related, so addressing diet and vitamin intake is helpful
- Hydrogen Peroxide - posited as a key alleviating treatment (not a cure) on a popular website, it is used in dilutions between 3% and 27% strength, but side-effects of its use include burning and itching, and there is argument as to whether it only attacks the 'sick cells'.
- Potassium permanganate dilute solution soaks - also popular, and used to 'dry out' the vesicles, but can also be very painful and cause significant burning.
- Domeboro (OTC) helps alleviate itching in the short term.
- Emollients during the drying/scaling phase of the condition, to prevent cracking and itching.  While petroleum jelly may work well as a barrier cream, it does not absorb into the skin and or allow it to breathe, so may actually be less helpful.
- Salt soaks
- White vinegar soaks
- Avoidance of known triggers - dyshidrosis sufferers may need to abstain from washing their own hair or bodies, or wearing gloves when they do so, however waterproof gloves are often potential irritants.
- Zinc oxide ointment
- Nickel-free diets
- When in the scaling phase of the condition, the scales may cause deep cracks and fissures in the skin.  Filing (as with an emery board) may help to minimize this.
- Stress management counseling
- Light treatment: UVA-1, PUVA, Grenz Rays, Low Level Light Therapy using a Red + NIR (LED) combination
- Ciclosporin a strong immunosuppressant drug used to combat dyshidrosis caused by ulcerative colitis
- Efalizumab (Raptiva) a medication used to treat psoriasis
- Tacrolimus and Pimecrolimus, potent immunomodulators often used to prevent organ rejection in topical, ointment form, may be used in severe cases.
- Unbleached cotton gloves may be used to cover the hands to prevent scratching and vulnerability of the skin to bacteria
- Plantain (Plantago major) infused in olive or other oil can be soothing.
- Band-Aid brand liquid bandage regularly applied during the (often painful) peeling stage allows the skin to breathe while protecting it from further irritation. Some suffers have found that with regular application the skin will close and reform within 1 to 2 days. Protection is sufficient that the user can (gently) wash their hands with no irritation, however additional application after each hand wash is suggested. It does not cure the condition and only aids healing during the peeling stage. Other spray-on or brush-on liquid bandaids can contain irritating ingredients and have not been found to be helpful, some will aggravate the condition significantly.
- Avoid metal computer keyboards and track pads which contain nickel.
Many sufferers of dyshidrosis will find that treatments that were previously suitable for them no longer work or have induced sensitive reactions, which is common in most types of eczema.
- It may be prudent to wear light cotton gloves while reading newspapers, books and magazines. The inks and paper may irritate the condition.
- Avoid Purell and other hand sanitizing products which contain alcohol. These may aggravate the condition.
- Wash affected hands and feet with cool water and apply a moisturizer as soon as possible.
- Valium in small doses during flare ups

# Allergy testing
Allergy testing is a contested subject among eczema communities.  Some dermatologists posit that if a sufferer is allergic to a substance, then a general allergy test on the forearm will suffice, yet others believe that in conditions like dyshidrosis, the suspect substances need to be applied to the affected area to induce a reaction.