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21/09/2023It is often wrongly assumed that dyshidrosis is a sweating disorder. This confusion usually comes from the condition’s name and its palmoplantar site; however, sweating is not a symptom of dyshidrosis.
What does dyshidrosis look like?
Dyshidrosis causes the sudden appearance of fluid-filled vesicles under the skin on the sole of the foot or inbetween the toes. The vesicles cause bumps in the skin that are shiny, domed and filled with a thick, sticky liquid. The number of vesicles that appear can vary from a few to up to a hundred.
Plantar dyshidrosis
As on the palms of the hands, eruptions of vesicles can appear on the feet, particularly on the soles. The number of vesicles that appear can vary from a few to up to a hundred, and sometimes they clump together causing a vesicular plaque that will eventually erode.
Bullous dyshidrosis
In particularly aggressive cases of dyshidrosis, blisters can form instead of vesicles. They are domed, contain a thick, sticky liquid and can cause a great deal of irritation and pain.
Pustular dyshidrosis
In some cases of dyshidrosis, pustules can form. While antibiotics are often prescribed for this condition, it is not actually an infection but a reaction of the skin rendering antibiotics unnecessary.
What causes dyshidrosis?
Dyshidrosis is a dysreactive disorder whereby many leukocyte cells are brought into the skin, causing
dyshidrosic vesicles, blisters or pustules to form.
Dyshidrosis is on the spectrum of psoriasis or atopic dermatitis, which are both auto-inflammatory in nature, with a chronic, relapsing course.
As with psoriasis or atopic dermatitis, there are many triggers for but no real cause of dyshidrosis.
Some triggers for plantar dyshidrosis include stress, the changing seasons, contact with irritants, concomitant streptococcal infections, and concomitant fungal infections (dermatophytes).
Fake news: presumed causes of dyshidrosis
As with many other conditions with unknown causes, there are many supposed roots of dyshidrosis but none of which are supported by scientific data. The most common of these theories are listed and debunked below.
Nickel allergy
Individuals suffering from dyshidrosis are largely atopic and, as such, sensible to nickel. However, nickel is not a cause of dyshidrosis, but is a trigger of contact eczema. Adopting a nickel-free diet does not, therefore, benefit those with dyshidrosis.
Histamine
Histamine is present in many foods and other foodstuffs contain substances that cause histamine to be released from cells. Histamine is a cause of urticaria, for which adopting a histamine-free diet may help. However it is not a cause of dyshidrosis and, therefore, having such a diet would have no benefits.
Gut dysbiosis
Many believe that the cause of chronic disease is related to the intestinal flora or imbalances within the gut. For this, probiotics and special diets are often encouraged but, again, they will not provide any improvements in cases of dyshidrosis.
Candida
Recently, the theory that candida overgrowth is a cause of dyshidrosis has become more widespread. Candida is a yeast found in the intestines and aids in digestion. Antifungals to treat candida overgrowth (yeast infections) are harmful and, moreover, do not tackle dyshidrosis.
Allergies and autoimmunity
As with psoriasis and atopic dermatitis, there are also many theories that link dyshidrosis to allergies or autoimmunity. Confirming the presence of an allergy or autoimmunity involves numerous tests that can cause great confusion and could result in immunosuppressive therapies being implemented, which can worsen dyshidrosis.
Cortisone and dyshidrosis
As with most inflammatory skin diseases with an unknown cause, dermatologists or other physicians unfortunately often end up prescribing cortisone. Whether taken orally or locally, cortisone is an anti-inflammatory medication and will initially reduce symptoms of dyshidrosis and may lead to its complete remission. This, however, is solely an ephemeral result and, as soon as cortisone application is reduced or suspended, there is usually a “rebound” effect where dyshidrosis will reappear, often more acutely than before.
If the patient continues using cortisone without interruption, there is still a risk. Over time, tachyphylaxis could occur whereby the cortisone gradually loses control over the dyshidrosis and more applications/doses are needed to contain the condition. Eventually, the patient will be completely dependent on cortisone, which can cause cortisone damage to both the skin and body, without, however, ever truly having resolved dyshidrosis.
Dyshidrosis: DermaClub suggests
Treating dyshidrosis is not an easy feat, but two important steps towards its resolution are to prevent irritation and reduce symtpoms.
Reduce irritation
Dyshidrosis is an inflammatory skin disease. This means that any stress applied to the skin will result in further inflammation and new flare-ups of dyshidrosis. However, completely avoiding stress can be difficult, as the hands and feet are constantly subjected to many, often unavoidable stresses, such as walking or washing the hands. The frequency and intensity of the latter is one stressor that can be controlled, as washing with water and detergents should be considered as an aggravator for areas with dyshidrosis. Instead, use nitrile gloves on the hands when washing or when touching potential irritants, including dust and household chemicals. For the feet, dry wash once a day with potassium permanganate solution.
Reduction of symptoms
To avoid the detrimental effects of cortisone, the following naturally-occurring reducing agents can be used to treat dyshidrosis: salicylic acid, sulfur, allantoin, ichthyol sulfonate and coal tar.
The sulfosalicylic 2S Cream is anti-inflammatory, while PEG Ointment (polyethylene glycols ointment with allantoin) has restorative properties. Meanwhile, Dermicitol Cream (ichthyol sulfonate) reduces and counters inflammation.
Apply either 2S Cream or Dermictiol Cream every evening, followed by PEG Ointment the following morning. For each cream, apply a small amount of product and massage well.
Coal tar cream has excellent reductive, anti-inflammatory and restorative properties but must only be used in the autumn or winter seasons due to the increased photosensitivity that it causes. While this cream is not commercially available in Italy, it can be purchased online. In countries such as the UK, some products containing coal tar are available in pharmacies.