Warts: causes, symptoms, diagnosis, treatment

Warts (verrucae vulgaris) are common soft epidermal growths associated with human papillomavirus infection. They can occur anywhere on the body. Diagnosis is made by examination. Warts can be removed by excision, cauterization, cryotherapy, liquid nitrogen, injections, or topical wart treatment.

What causes warts?

At present, at least 60 types of human papillomavirus have been identified. None of them is strictly specific to a particular type of wart. However, with common warts, type 2 is most often found; with flat warts, type 3; with plantar warts, type 1 (in the case of mosaic warts, type 4); with pointed condylomas, types 6 and 11.

Warts are common, at any age, but most often develop in children, almost never in old age. Warts are caused by human papillomavirus (HPV) infection, at least 70 types of HPV are associated with skin lesions. Trauma and maceration facilitate initial epidermal penetration. Local and systemic immune factors are believed to influence the spread of infection. At risk are patients with reduced immunity, such as those with HIV and after kidney transplantation, when extensive lesions may develop that are difficult to treat. Humoral immunity provides resistance to HPV, and cellular immunity leads to regression.

Pathomorphology of warts

Characteristic signs are hyperkeratosis, sometimes with areas of parakeratosis, papillomatosis. Epithelial outgrowths are long and directed by their ends from the periphery to the center of the lesion, located radially in relation to it. The cells of the upper part of the spinous and granular layers are vacuolated, do not contain keratohyalin granules. Their nuclei are rounder, sharply basophilic, surrounded by a light rim.

Electron microscopy reveals viral particles in these cells. However, such cells are not always present. As a rule, there are no changes in the dermis, but during the period of regression of the rash, mononuclear infiltration and exocytosis appear in it, which some authors consider an immune reaction.

Common warts

A common wart is differentiated from various papillomatous growths, from which it differs by the presence of the vacuolated cells described above, as well as the radial arrangement of epidermal growths.

Flat warts

Flat warts are characterized by cytosis and hyperkeratosis with a greater number of vacuolated cells in the upper part of the spinous and granular layers, as well as in the stratum corneum, giving it a basket-weave appearance. The basal layer sometimes contains a large amount of melanin.

A flat wart differs from a common wart by the absence of papillomatosis, parakeratosis, and more pronounced vacuolization of cells. The latter feature makes a flat wart similar to verruciform epidermodysplasia of Lewandowsky-Lutz, however, WF Lever (1975) notes more pronounced pycnosis of nuclei in verruciform dysplasia.

[ 1 ], [ 2 ], [ 3 ], [ 4 ], [ 5 ], [ 6 ], [ 7 ]

Plantar warts

There is marked hyperkeratosis and parakeratosis with large, round, sharply basophilic nuclei in the stratum corneum. In fresh lesions of the upper part of the spinous and granular layers, a large number of vacuolated cells may be observed. The histological picture resembles that of a common wart, but is distinguished by more marked hyperkeratosis and parakeratosis, as well as a large number of vacuolated cells.

Pointed condyloma

In pointed condylomas, the stratum corneum consists of parakeratotic cells, and the granular layer is absent. The epidermis is in a state of acanthosis and pronounced papillomatosis with thickening and elongation of branching epidermal outgrowths, which resembles pseudo-epitheliomatous hyperplasia. Vacuolization of the upper layers of the epidermis is characteristic, which makes them similar to common warts. The dermis is sharply edematous, its vessels are dilated, focal inflammatory infiltrates are noted. Giant condylomas at first glance resemble a cancerous tumor due to the deep immersion of epithelial strands into the dermis, but a thorough examination can establish the benign nature of the process.

The virus reproduces only in highly differentiated epithelium, which makes it difficult to obtain in culture. Using the in situ hybridization reaction, it was shown that viral DNA is synthesized in the upper layers of the spinous layer, and complete capsid frillation occurs in the cells of the granular layer. Infection is facilitated by microtraumas of the epithelial cover, decreased cellular immunity, which is confirmed by the increased occurrence of warts with immunodeficiency states, including those caused by the human immunodeficiency virus. Giant warts develop due to hyperhidrosis, phimosis, and other disorders.

How do warts appear?

Warts are named according to their location and clinical manifestations; different forms are associated with different types of HPV.

Common warts (vulgar warts) are caused by HPV 1, 2, 4, 27 and 29. There are no symptoms, sometimes there is mild pain, especially if the warts are located in places subject to pressure, such as on the feet. Warts have a clearly defined, round or uneven shape. The elements are rough, hard, light gray, yellow, brown or gray-black in color, 2-10 mm in diameter, most often appear on the fingers, elbows, knees, face. Warts of an unusual shape, for example on a leg, most often appear on the head, neck, especially on the chin.

Filiform warts (papillomas) are long, narrow, and usually form on the eyelids, face, neck, or lips. They are also asymptomatic. This type is benign and easy to treat.

Flat warts, caused by HPV types 3, 10, 28, and 49, are smooth, yellow-brown, flat-topped papules most commonly found on the face. They are most common in children and young adults. They are usually not bothersome, but are difficult to treat.

Palmar and plantar warts caused by HPV1 are flattened by the pressure of the lesion and are surrounded by thickened skin. The lesions are often tender, causing discomfort when walking. Warts can be distinguished from calluses and corns by the presence of pinpoint bleeding when they are damaged. Warts are thought to be painful when pressed laterally, and calluses are painful when pressed directly, but this is an unreliable sign.

Mosaic warts are papules formed by the joining together of countless small, closely spaced warts on the feet.

Like other plantar warts, they are often painful.

Periungual warts appear as thickened, slit-like, cauliflower-like lesions around the nail plate. The cuticle is often damaged and paronychia develops. This type of wart is prevalent in patients who bite their nails.

Pointed warts (condylomas) appear as smooth or velvety papules in the anogenital and pararectal area, on the labia or penis. Types of HPV 16 and 18 are the main causes of cervical cancer. They are usually asymptomatic.

Types of warts

Common warts are single or small multiple, dense, sharply defined nodular elements without signs of inflammation, with an uneven papillomatous surface, the color of normal skin or grayish-yellow. They are located mainly on the back of the hands and feet, including around the nail plates and under them, but can be in any area of the skin, on the red border of the lips, the mucous membrane of the oral cavity. The wart that appears first is larger in size.

Flat warts, unlike common ones, are more numerous, smaller, have a smooth surface, and develop mainly in children and young women. They are located mainly on the face and hands, knee joints, often linearly, as a result of the Koebner phenomenon.

Plantar warts are characterized by sharp pain, deep location, large size (up to 2 cm in diameter), pronounced horny layers, after removal of which a papillary, often bleeding surface is revealed. These warts are usually few in number. They are located in places of greatest pressure. The skin pattern in the area of the warts is disrupted. With close arrangement of individual warts, the lesion can take on a mosaic character.

Pointed condylomas are soft papillomatous growths, usually located in the anogenital area, resembling cauliflower in appearance, often with a macerated surface. Giant forms may be observed, representing warty growths that merge with each other to form a large pink or red lesion in the form of cauliflower, soft in consistency with a lobular, moist, macerated surface, often with bleeding cracks. They develop on the genitals, around the anus. Giant condylomas are found, located mainly on the head of the penis. Clinically, they may resemble carcinoma. Such condylomas can transform into cancer. WF Lever and G. Schaumburg-Lever (1983) consider giant condyloma to be warty epithelioma. PO Simmons (1983), however, believes that giant condylomas, although they can destroy tissue, will remain histologically benign.

How to recognize warts?

Diagnosis is based on clinical manifestations; biopsy is rarely required. The main symptom of warts is the absence of a skin pattern on their surface, the presence of black dots (clogged capillaries) or bleeding when the surface is damaged. In diagnosis, calluses, lichen planus, seborrheic keratosis, polyps and squamous cell carcinoma should be distinguished. DNA typing is available in some medical centers, but is usually not necessary.

How to get rid of warts?

Warts may suddenly disappear, or persist for many years, or reappear in the same or different places, even after treatment. In patients prone to frequent injuries (athletes, mechanics, butchers), the course of HPV may become persistent. HPV in the genital area is usually malignant.

Treatment of warts is aimed at stimulating the immune response to HPV. In most cases, this is achieved by using irritants (salicylic, trichloroacetic acid, 5-fluorouracil, tretinoin, cantharidin, podophyllin).

These compounds can be used in combination or together with cryosurgery, electrocautery, curettage, laser. Direct antiviral effect is provided by bleomycin and interferon a2b, but this treatment should be used in case of persistent course of the disease. Local application of 5% imiquimod cream stimulates cells to produce antiviral cytokines. For local treatment cidofovir, vaccines and contact immunotherapy are used. Oral drugs include cimetidine, isotretinoin, zinc. In most cases it is necessary to combine different forms of treatment to increase the probability of success.

How to get rid of common warts?

Common warts may disappear within 2 years, but some persist for many years. Various treatments are available. Warts can be removed using electrocautery, cryosurgery with liquid nitrogen, and salicylic acid preparations. The use of these methods varies depending on the location and severity of the lesion. For example, 17% liquid salicylic acid is used on the toes, while 40% can be used on the soles.

The most commonly used topical preparation is salicylic acid, which is available in liquid form as a patch. Salicylic acid is applied at night and left on for 8-48 hours, depending on the affected area.

Cantharidin can be used alone or in combination (1%) with salicylic acid (3%) podophyllin (2%) in a collodion base. Cantharidin is removed with soap and water after 6 hours, cantharidin with salicylic acid or podophyllin is removed after 2 hours. With prolonged contact with the skin, the possibility of blisters formation increases.

Warts can be removed using cryosurgery; it is painful but extremely effective. Electrovaporation with curettage and/or laser surgery is effective and is used for isolated lesions, but scarring may occur. Warts recur or develop new ones in 35% of patients within a year, so methods that cause scarring should be avoided.

How to get rid of papillomas?

Treatment involves scalpel removal, curettage or liquid nitrogen. When using liquid nitrogen, 2 mm of skin surrounding the wart should turn white. Blisters may develop 24-48 hours after treatment. Care must be taken when treating warts on the face and neck, as hypopigmentation may develop after using liquid nitrogen.

How to get rid of flat warts?

The treatment involves daily application of tretinoin (retinoic acid 0.05% cream). If this is not enough, 5% benzoyl peroxide or 5% salicylic acid cream should be added. Imiquimod 5% cream can be used alone or in combination with topical preparations. In general, flat warts are difficult to treat and get rid of warts.

How to get rid of plantar warts?

Treatment requires thorough softening. A 40% salicylic acid patch is applied and left on for several days. The wart is softened and then destroyed by freezing or by using caustic substances (30-70% trichloroacetic acid). The use of a CO2 laser and various acids is also effective.

How to get rid of periungual warts?

Warts can be effectively removed using a combination treatment using liquid nitrogen and 5% imiquimod cream, tretinoin, or salicylic acid.

How to get rid of stubborn warts?

Several treatments are available for recalcitrant warts. Injection of 0.1% bleomycin is used for plantar and periungual warts, but may cause Raynaud's phenomenon or vascular damage (especially when injected into the base of the finger). Interferon may be used (three times a week for 35 weeks). Oral isotretinoin or acitretin may improve or resolve large lesions. Cimetidine up to 800 mg orally three times a day has been used successfully, but is more effective when combined with other drugs.