Warts are benign growths (hyperplasias) of the skin which are caused by the Human Papilloma Virus – HPV. More than 70 HPV types have been implicated for the development of warts. It is believed that certain types of viruses cause warts in specific parts of the body.
Although, warts constitute a benign condition, they cause a concern to patients as they may cause pain or they may bleed; if their site of localization is on the feet then they may hamper walking. This virus causes a rapid proliferation of skin cells resulting in the development of warts, i.e. benign bumps in the form of a cauliflower. Warts are the second most common skin disease following acne. Children and young people are more often affected by warts due to the immature immune system of these individuals, although their occurrence at any age cannot be excluded.
Warts usually occur on the hands, the feet and the face. However, any part of the body can be affected by warts. Warts occur most commonly in the summer because of the non use of shoes and the increased contact with water which makes the skin more susceptible to viral attack.
Warts can also be transmitted in swimming pools, as HPV viruses are resistant to chlorine. Thus, contact with bare feet in an environment where the virus may exist leads to its transmission.
Warts are transmitted by towels due to the same reason, since virus is highly resistant and can live in infected objects for at least 6 days. Warts are often transmitted by autoinoculation at injury sites. For example, warts on the palms may lead to facial warts or warts to any other part of the body following contact with the infected area.
Depending on their clinical presentation, warts are divided in the following categories:
Common warts (Verruca vulgaris)
Common warts can be round or may have irregular shape with white, grey or brown color and may be flat or raised in the size of a pea. Common warts usually develop around the nails, the fingers and the back of the palm, but can also occur on the knees and the face, in cases where the skin has been injured. Common wart symptoms are not particular significant, apart from those which develop in specific sites.
Flat (plane) warts (Verruca plana)
Flat warts are asymptomatic, slightly raised or flat lesions with a smooth surface and light brown or grey-yellow color. Flat warts are usually found on the forehead, the dorsal surface of the hands, the chin, the neck and the feet, and may be typically be arranged in a line as a result of their inoculation due to scratching of the area (warts – Koebner phenomenon).
Papular warts usually occur in men, are distributed on the face and the neck and are often confluent. These warts often form small groups at the beard of men and the scalp.
Filiform or digitate warts
These warts resemble papillomas and are mainly located on the sides of the neck, armpits and the folds on the thighs and the genitals. The wart is also called verrucous papilloma and proliferates by friction and the use of chains around the neck.
Plantar warts occur as a well defined circular lesion with rough hyperkeratotic surface. They have a skin color and if their thick coating is removed, blackheads are observed which are pathognomonic for the disease. Plantar warts are usually formed at the sole areas that feel the most pressure. In women, plantar warts prefer the front part beneath the fingers. In some cases, plantar warts may cluster creating plaques resembling a “mosaic”.
Plantar warts are usually extremely painful if left untreated and cause difficulty and severe pain in walking. Plantar warts, due to the pressure from walking, normally do not grow in the form of lumps but in the form of hard nodules. Thus, in case of plantar warts a differential diagnosis should be made to exclude the possible presence of a foot callus (bunion).
Palmer warts (Periungual warts)
This is the most frequent localization of warts. Palmer warts are very common. They can be detected on the palm or the back of the hands. Palmer warts are often found around the nails, and are thus called periungual warts.
Palmer warts are a common manifestation in children since children can touch contaminated objects with their hands, and they do not yet have a strong immune system to protect them against the infection. Palmer warts usually occur in people who because of their work have constant contact with water, e.g. housewives and hairdressers. Finger warts that commonly occur in these people cause intense discomfort and pain that hampers their work.
Finger warts can occur either around the nails, or the palmar surface. Finger warts are often located between the digits and present severe pain or even bleeding. Due to the prolonged wetting, the skin becomes more vulnerable resulting in the development of palmar warts and periungual warts.
A common site of wart manifestation is the face. Facial warts usually occur in children and are mostly asymptomatic. Facial warts are smooth and flat and often multiply due of scratching.
Facial warts are often an aesthetic problem for the patient. Special caution is required by the Dermatologist to make the correct diagnosis and treatment of warts as well as to make a differential diagnosis, distinguishing them from possible hyperplasias and moles.
Genital warts (commonly known as condylomata, Condyloma acuminatum)
These warts are actually the known genital (anogenital) warts which may not have been transmitted by sexual intercourse, but with palmar wart infection.
HPV types 2 and HPV 4 are responsible for common warts. Other types of viruses are HPV 1, HPV 3, 26, 29 and 57.
The HPV types 16 and 18 are considered high risk, and are associated with malformations and cervical cancer.
The same applies for HPV types 58, 33, 45, 31, 52, 35, 39 and 59. These types are not associated with warts but with vulvar, vaginal, penile and anal cancer, as well as cancer of the oropharyngeal cavity.
The HPV types 1, 2, 3, 4, 27, 28 and 58 have been implicated for the occurrence of plantar warts, whereas the HPV types 3, 10 and 38 cause flat warts.
Genital warts (condylomata) are caused by HPV types 6, 11, 42 and 44
But sometimes they can cause itching (pruritus) which leads to severe scratching as well as to their spread.
Palmar and plantar warts are usually painful. During manual work they cause pain and intense discomfort; the same applies for plantar warts during walking. Palmar and plantar warts may bleed upon pressure as it occurs in walking. Intense pain can also occur in subungual warts which are basically warts that grow under the nail leading to nail detachment and intense discomfort in upper and lower extremities.
Filiform warts which are found in the neck and the trunk can be injured, detached, bleed and become infected causing severe pain and inflammation requiring immediate treatment. Wart diagnosis should exclusively be made by a dermatologist, since other lesions such as skin cancers can mimic the occurrence of a wart. Thus, when a wart grows quickly, bleeds, changes color or proliferates we should immediately address a specialist.
Children are very often affected by warts. The immaturity of their immune system and the lack of antibodies against HPV contribute to the easy growth and proliferation of warts in children. In children, warts do not present particularities both in symptoms and treatment and are usually found on the hands, the legs and the face.
In children, warts tend to be more flat and soft relative to the ones seen in adults due to their thinner skin. They can be easily transmitted, as it is not easy for children to follow the rules of hygiene, they touch everything with their hands and tend to walk barefoot.
Wart treatment in children is mainly done with laser and cryotherapy, as the use of acids and caustics is contraindicated in young ages. Recurrences occur often and wart treatment in children may be long-term in order for the virus to be completely eradicated.
In rare cases, for the confirmation of diagnosis a biopsy may be needed, mainly if the clinical picture resembles epitheliomas or skin carcinomas in adults. The histology of warts is characteristic, as there is thickening of all layers of the epidermis and occurrence of koilocytes which are pathognomonic. The detection of wart viral type with a special test called polymerase chain reaction (PCR) is not recommended and is not performed in practice, since the result would not change the treatment plan.
Walking with bare feet around swimming pools and contact with the sand must be avoided because the virus responsible for the development of warts may live there for several days.
For the prevention of wart transmission it is mandatory people who present warts to avoid the use of swimming pools until cure is achieved
The use of individual towel prevents the transmission of warts
Treatment of warts immediately after their occurrence prevents autoinoculation and transmission of the infection to others
Highest success rates in treating warts are achieved by CO2 laser that completely destroys the lesion even in a single session. Wart treatment in our clinic is mainly performed by laser, as this type of treatment has the lowest rates of recurrence.
The advantages of laser wart treatment are the following:Atraumatic and non invasive method Does not leave marks and scars It targets the wart tissue leaving intact the surrounding healthy skin It penetrates deep and even destroys the “root” of the wart Only one session may be required to achieve eradication and the patient leaves the clinic being cured Wart laser treatment is associated with lower recurrence rate (i.e., there is less chance of recurrence of the wart following laser treatment in comparison to other methods)
Treatment of warts may also be achieved with cryotherapy, where liquid nitrogen is used. Diathermy coagulation as a method for wart treatment does not constitute a first-choice treatment, as it is associated with greater trauma and scarring.
Treating warts using caustic substances and retinoids is contraindicated in children. One should be very careful and cautious of wart treatment methods that are offered by non-physicians because they have dubious outcomes and may be hazardous.
Treatment of warts must exclusively be made by a dermatologist.