Treating warts in practice: necessary and challenging

Warts are caused by a viral infection. This means there is no definitive, causal treatment. Anja Stoffel describes below what podiatrists should look out for.

There are various types of warts, which are classified and described differently depending on their appearance, the type of pathogen and the area of the body. On the foot, the most common type is the Verruca vulgaris or Verruca plantaris. This description is topographical – meaning a ‘normal’ wart, specifically on the foot. As the virus stimulates the skin to grow rapidly and causes local hyperkeratosis, this results in the characteristic raised, cauliflower-like, fissured growth. In areas of the foot subject to pressure, this hyperkeratosis is pressed into the foot by body weight then, whilst walking, causing painful pressure to irritate the tissue (‘plantar wart’ or ‘spur wart’).

For those affected, warts are always a nuisance, sometimes extremely painful depending on their location (under the nail, at sensitive friction points), and a source of embarrassment thanks to the risk of infection. When irritated or during “active phases”, verrucae tend to spread in clusters and cause significant distress, which is why their treatment by a podiatrist is necessary but also challenging.

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HPV viruses are transmitted through skin contact, in most cases via a point of entry or a compromised skin barrier. People whose hydrolipid film is compromised due to illness, or whose skin is stressed and at risk due to certain behaviours, are especially vulnerable to infection. These include, for example:

• People who have an immune deficiency (illness, chemotherapy, immunosuppression, diabetes mellitus and different conditions)
• Periods of hormonal change (growth and puberty, menopause)
• Frequently macerated skin (swimming pools, winter and rubber boots, safety footwear, sweaty skin; people with cold, clammy, damp feet)
• Skin barrier disruption thanks to chronic skin conditions such as atopic dermatitis or entirely very thin, sensitive skin
• Feet subjected to strain thanks to sport (damp environment, tight trainers, injuries, blisters, pressure and shear forces)
• Walking barefoot on contaminated surfaces in public areas (changing rooms, showers, swimming pools), particularly reinforced by micro-injuries and maceration caused by sport and moisture

Warts are generally harmless. However, warts that itch severely, change rapidly, ooze fluid, change colour or become entirely conspicuous should be examined, as the rapidly proliferating tissue can, in rare cases, become malignant. Warts are diagnosed by a dermatologist through visual examination using a magnifying glass; samples are only taken in cases of suspicion. Podiatrists can also discover warts by their typical appearance:

• cauliflower-like, fissured surface
• raised in non-weight-bearing areas, small bulges of loose, whitish hyperkeratosis
• often small micro-blood vessels/papillae (brown dots)
• high tendency to bleed during filing or when scratched in pressure-bearing areas; growth inwards; pain during the lateral squeeze test (an indication, not a definitive diagnosis): pressure from the side is painful, pressure from above less so

Unlike clavus, warts are found not only in pressure-bearing areas but all over the foot. The skin is rather soft, whitish, loose and fissured. Also typical of verrucae are the small sprouting vessels and the tendency to bleed, which are not present in the hard, glassy horny core of a clavus.

The treatment includes various possible options, all of which aim to remove the upper, virus-carrying layers of skin—along with the virus—more or less quickly and aggressively, then allowing the healthy skin to regenerate. Additional supportive measures may also be considered.

Mechanical, layer-by-layer filing:
Over a long period, the skin is treated in such a way that it peels away in layers, allowing virus-infected tissue to be removed step by step. Caustic agents, soaking, cryotherapy or lasers fall into this category. Similarly, surgical removal using a sharp curette can be performed in a single session (as opposed to the step-by-step approach), though this frequently has the effect of causing unsightly, thickened calluses. These can cause discomfort for a lifetime and require regular filing, which is why the surgical approach should be carefully considered.

Strengthening the immune system and promoting self-healing:
Alternative healing methods, homeopathy, tinctures containing natural, germ-inhibiting or astringent ingredients (banana peel, garlic, ginger juice), and treatments such as cupping, etc., can be highly effective.

Newer methods aim to disinfect the tissue and kill the HPV virus, as it is possible with cold plasma or PACT therapy. Another successful, albeit rather drastic, action involves inserting a needle into the centre of the wart under local anaesthesia (Falkner’s needling), then triggering irritation, inflammation and a subsequent healing cascade (Bajeva et al., 2020); the success rate stands at almost 70 per cent complete healing (!), with at least a significant improvement occurring in 17 per cent of cases. Conversely, just over ten per cent of those treated did not respond at all to the needle therapy.

Interesting: The now widely used HPV vaccination for cervical cancer prevention in girls has not shown any change in the occurrence or growth of warts, presumably due to the different HPV strains (>100). Possible useful correlations are being further observed and researched.

Important: Whether treatment is required or not depends on the health problems. If there are no health problems, manipulation is not recommended. Working on the wart can lead to a temporary worsening of the condition, which is why a stable phase without discomfort or limitations can be left as it is. The verruca should be fully covered and left alone, and should also be left undisturbed at home.

If health problems are present, treatment should be planned jointly and, if carried out by a podiatrist, must be approved by a doctor or covered by a sectoral alternative practitioner’s licence.

As there is no causal, guaranteed treatment for a viral infection, counselling patients is of crucial importance; it is a sign of professionalism to discuss the uncertain prognosis together: even though there are many positive experiences, the practitioner then prevents patient dissatisfaction. The possibility of a disadvantage (inflammation, spread, bleeding and pain) during the course of treatment should also be addressed, as every immune system and every skin reacts differently to stimuli, and the treatment is always accompanied by irritation.

The following applies to filing: if the skin is to be healed and the verruca treated, then as much of the whitish, loose keratotic layer as possible must be removed as deeply as possible using a scalpel or hollow chisel (always taking the patient’s condition on the day into account). With you, hand instruments should be used, as grinding can spread infected keratinous material into healthy tissue, increasing the risk of secondary warts. Similarly, patients must under no circumstances attempt to work on the affected area themselves using, for example, a pumice stone or a file, for the same reasons.

Warts bleed easily, and bleeding during filing can sometimes not be avoided. If numerous papillae are visible, the likelihood of bleeding is also high. Nevertheless, it can be necessary to file the callus. So that initial wound care is planned, the patient’s understanding and cooperation are reserved in advance. Topical treatments such as caustic agents or keratolytics should not be applied directly to open wounds. There is no risk of infection from bleeding, as only the keratinised material transmits pathogens, not the exuding fluid or blood (Witchey et al, 2018).

Disadvantage of the condition

If the verruca tissue itself becomes inflamed, this can be interpreted as a desired rejection reaction (see Fig. 2). This is highly unpleasant and painful for the patient; however, the inflammatory process also causes the affected upper layer of tissue to slough off, which often results in complete healing. Highly thorough prior explanation and close monitoring are crucial to dispel any allegations of medical negligence and also to get through the unpleasant rejection phase.

Warts are HPV viral infections of the epidermis No proven curative treatment available Treatment must be established by a doctor and delegated; secondary medical licence required No treatment if there is no problem; both worsening and spontaneous healing are possible
Documentation of the consultation and patient information

• Treatment includes removing the infected tissue and optional further topical actions until complete regeneration
• Podiatric filing using hand instruments. Meticulous hygiene is essential, as keratinous material and blood are considered carriers
• Patient: do not scrape it off yourself and avoid mechanical irritation (protection during sport)
• Numerous supportive alternative healing methods (e.g. dandelion juice, thuja globules, banana peel, garlic).
• Keratolysis to soften the surface: Verrumal, salicylic acid tinctures
• Chemical treatment: establish the patient’s general condition and proceed only if it permits (check for neuropathy and similar conditions). Formic acid, monochloroacetic acid. In most cases, the denatured protein must be filed until the tissue has regenerated.
• Cryotherapy
• Light therapy (laser)
• PACT
• Cold plasma
• Surgical excision
  
  

Captions:
Image 1: Young female patient with damp, clammy feet and a painful ‘mother-daughter wart cluster’ on the forefoot. The treatment included cauterisation with monochloroacetic acid and filing, resulting in an inflammatory reaction with sloughing.
Image 2: Shows the acute condition following sloughing and filing.
Images 3–6: Patient following a kidney transplant and subsequent immunosuppression. Extensive verruca patches covering both forefoot areas and toes (the images show only the right foot; both sides were similarly affected). The treatment included mechanical relief, i.e. ‘only’ filing at three-week intervals, without further actions due to the extent of the condition and the patient’s immune status. After several months, a sudden, dramatic spontaneous remission occurred – the presumed reason was the birth of the first grandchild and, as a result, self-healing.

Author: Anja Stoffel
All images: @Verlag Neuer Merkur

About the journal of podiatry

The specialist journal PODOLOGIE is one of the leading publications for podiatrists and medical foot care professionals in German-speaking countries. With in-depth expert articles, practical case reports and the latest information from the worlds of science, law and practice, it supports its readers in their day-to-day professional lives and provides an important platform for professional exchange. Interested parties can choose between various subscription options – from the print edition to digital access. Further information on subscriptions can be found at: www.podologie.de/abos