Hand Eczema and Food Allergies

‘Doctor, there are tiny bubbles on my palms, and they are extremely itchy. I cannot sleep! Am I allergic to something?’ This is a common encounter in the consultation room. This article explores hand eczema – a common skin inflammation and its correlation with our diet.

What is Pompholyx/Dyshidrotic eczema?

Pompholyx is a type of eczema, also known as dyshidrotic eczema. It is a type of skin condition that affects the hands and feet. Eczema is a chronic inflammatory skin condition that causes intermittent itchy red rashes (of various forms) that can occur on any part of the skin. In pompholyx, eczema mainly targets the palms of the hand and soles of the feet. It is commonly seen in women and those under the age of 40.

What does pompholyx/dyshidrotic eczema look like?

In dyshidrotic eczema, one presents with deep-seated tiny, multiple watery blisters that are immensely itchy and uncomfortable over the hands and feet. Over time, the blisters can become weepy, especially when broken, and one will be susceptible to bacterial infection. This further causes skin inflammation with swelling, discomfort, pain and itch. The weepy affected area will eventually dry out, leaving the skin dry and flaky with painful fissures and cracks. Patients with chronic symptoms of dyshidrotic eczema can have abnormal nail folds (skin surrounding the nails) and nail changes.

What are the possible triggers for pompholyx/dyshidrotic eczema?

The exact reasons for developing pompholyx remain unknown. Patients who develop dyshidrotic eczema are generally more atopy (sensitised to the surroundings – be it environment or food). They can be associated with atopic eczema, allergic rhinitis, and asthma and may have a family history of atopy as well.

Potential triggers of dyshidrotic eczema include the following:

• Stress
• Allergy to metal such as – nickel, cobalt, chromate, (jewellery, buttons, belt or bra hooks, money, utensils, or crockery items) 
• Allergy to rubber, dyes
• Heat, humidity
• Sweat
• Harsh detergent and wash, solvents, chemicals
• Food allergies

As individual patients may have different triggers and genetic predispositions, it is worth speaking to your trusted doctor regarding your symptoms, and your doctor can guide you further on the possible triggers in your case.

Food allergies and pompholyx/dyshidrotic eczema

Although the clinical evidence between eczema and food allergies remains much to be elucidated, it is worth exploring the relationship between dietary intake of nickel and dyshidrotic eczema.

Nickel is one of the common elementary microminerals found in most of our staple diets. It is clinically observed that nickel in diet can predispose an atopic person to dermatitis (skin inflammation), with the hands being one of the common sites associated with nickel dermatitis. A diet low in nickel has shown improvement in eczema conditions. Regarding pathophysiology, exposure to nickel may lead to ‘sensitisation’ of the body against nickel. Over time, with repeated exposure to nickel from the diet, the body develops an allergic reaction that manifests as skin inflammation.

Most dietary nickel comes from plant-based food. Food that are high in nickel content includes chocolate, oatmeal, rye, buckwheat, tea, liquorice, chickpeas, soya, nuts, almonds, lentils and legumes, broccoli, onion, garlic, leafy green vegetables, canned and processed food. (This is pretty much everything we eat daily!)

As nickel can be found in nearly all food, completely eliminating nickel from our daily diet is not feasible. However, the risk of exposure and sensitising a person with nickel in the context of dermatitis can be reduced with prudent food selection and a diet with low nickel concentration.

The caveat is that a low nickel diet does not guarantee a complete clear-up of dermatitis. Instead, a mindful diet practised over time may be associated with lesser or milder eczema flare-ups. 

You can speak to your doctor to understand further the association between food allergy and your skin condition. Depending on individual risks and skin conditions, your doctor may discuss further on allergy testing to evaluate further.

What may be expected when you see your doctor for dyshidrotic eczema?

Your doctor will obtain a relevant history of your symptoms and examine the rash on your hands and feet. Depending on the presentation and index of suspicion, your doctor may offer you other tests such as bacteria or fungal swab/scrape test or even scabies/syphilis screen to rule out other differential. If there is an allergy concern, your doctor may even offer you a skin prick test or blood RAST test. Do visit your doctor if you have a rash that does not resolve.

What will happen if I don’t treat dyshidrotic eczema?

Generally, dyshidrotic eczema is not a life-threatening condition. However, chronic severe eczema is known to be associated with significant reduction and impairment of quality of life. This is because the affected inflamed skin will become flaky and dry, and open wounds/bleeding may occur. The associated itch with dyshidrotic eczema can be intense and unbearable, which can impede the daily function of the affected body part.

What may mimic pompholyx/dyshidrotic eczema?

As dyshidrotic eczema presents with blisters over the hands and feet, the condition also mimics various infective conditions such as herpes, syphilis, or even hand-foot-mouth disease. Other differentials that have a similar appearance to dyshidrotic eczema include allergy/irritant skin inflammatory conditions and autoimmune blistering skin conditions.

It is worth letting your doctor look at the rash that affects your hands and feet. The medical treatment differs depending on the individual medical condition. If you are experiencing severe pompholyx/dyshidrotic eczema, see a healthcare professional rather than self-medicating with various ointments, creams, and over-the-counter medication that may worsen the condition further.

What is the treatment offered for pompholyx/ dyshidrotic eczema?

Treatment for pompholyx/dyshidrotic eczema depends on various factors such as severity, underlying conditions, and the individual's overall health. In general, treatment involves the following: 

• Precipitating factors or triggers of the symptoms – such as corrosive wash/detergent and known allergens, should be avoided.
• If the affected areas are weepy, your doctor may prescribe you a medication known as potassium permanganate to dry up the oozy region.
• Topical steroid or topical calcineurin inhibitors will be prescribed to the affected region to alleviate the skin inflammation.
• You are encouraged to apply emollient and moisturiser regularly to affected areas to improve the skin barrier.
• Oral antihistamine may be offered to alleviate your itching symptoms.
• Sometimes, if your doctor is concerned about associated infections, you will be prescribed oral antibiotics.

In severe dyshidrotic eczema or recalcitrant cases, second-line treatment such as phototherapy or oral immunosuppressants may be required to control the symptoms. You are advised to speak to your doctor regarding the symptoms and treatment you have tried. While the above is a general guide to treating dyshidrotic eczema, your doctor may tweak the treatment regimen to suit your condition and needs.

What should I do at home if I have pompholyx/dyshidrotic eczema?

If your pompholyx/dyshidrotic eczema is mild or you would like to try and manage your symptoms, consider the following:

• Gentle, lukewarm water for daily washing to minimise skin irritation.
• Use an emollient rather than a soap as a wash.
• Avoid direct contact with strong detergent or cleansing liquid. 
• Large blisters over the hands and feet can be expressed using a clean/sterile needle (your doctor can help you with that).
• Wear cotton clothing to allow an ‘airy and breathable skin’.
• If there is an open wound over the affected skin region, you can consider wrapping or bandaging the wound to avoid secondary infection.
• Ensure clean and breathable footwear, and avoid plastic or rubber shoes that can increase sweat production.

Some note-worthy thoughts…

Some people suffer only once in a lifetime episode of dyshidrotic eczema/pompholyx. Unfortunately, others may have a recurring and frustrating journey of skin inflammation. Good patient education on this common benign skin inflammatory condition is key for managing their skin with appropriate treatment and minimum exposure to possible triggers, including food triggers.

If you would like to learn more about eczema, dyshidrotic eczema, food allergy, or allergy in general, do feel free to reach out to your trusted clinician. 

References

1. Sharma AD. Low nickel diet in dermatology. Indian J Dermatol. 2013 May;58(3):240. 
2. Guillet MH, Wierzbicka E, Guillet S, Dagregorio G, Guillet G. A 3-Year Causative Study of Pompholyx in 120 Patients. Arch Dermatol. 2007;143(12):1504–1508. 
3. Sharma AD. Disulfiram and low nickel diet in the management of hand eczema: A clinical study. Indian J Dermatol Venereol Leprol. 2006;72:113–8.
4. Gawkrodger D J, Cook S W, Fell G S, Hunter J A. Nickel dermatitis: the reaction to oral nickel challenge. Br J Dermatol 1986: 115 33–38.
5. https://www.nhs.uk/conditions/pompholyx/
6. https://patient.info/skin-conditions/atopic-eczema/pompholyx