Wart: causes, types, and what it looks like

A wart is a small, firm nodule on the skin that is noticed by chance: on a finger, palm, knee, sometimes on the sole. Essentially it is a benign overgrowth of the superficial layers of the skin caused by the human papillomavirus. Below: what a wart looks like, how the types differ, and in which cases a wart should be shown to a doctor.

What a wart is and what it looks like

Formally, it is a benign skin neoplasm of viral etiology in the form of a nodule or papule. A wart is firm and rough to the touch; its color is usually close to the skin color, and on darker skin it looks darker. The size of a common wart ranges from a pinhead to a pea. Typical locations are the palms, fingers, joint areas, knees, and soles.

The incubation period is 2–5 months. Common warts can merge, forming large plaques. In children, warts often resolve on their own, while in adults they persist; spontaneous disappearance is described within two years, but sometimes it takes months and years.

Why warts appear: the role of the virus

The cause is the human papillomavirus. Each type is associated with its own strains: flat warts on the body, for example, with strains 14, 15, and 27. Transmission occurs through contact with a carrier, through shared items, contaminated surfaces, and close skin contact; infection is easier if the skin is wet or damaged.

A risk factor is a break in the integrity of the skin: small wounds, scratches, atopic dermatitis. Talk about a link between warts and cervical cancer does not apply to these growths: different HPV types behave differently.

Types of warts: vulgar, flat, mosaic

A vulgar wart is a firm, dry, circumscribed, painless, keratinized elevation with an uneven villous surface, most often on the hands. Its variant is the plantar wart: in areas of shoe pressure, especially in people who sweat heavily; it is very firm, grayish-dirty in color, and painful enough to interfere with walking.

Flat, or juvenile, warts are round or irregularly shaped nodules in children and young people, on the back of the hands and on the face; they appear along scratches and cuts, in areas of frequent shaving, and may be yellowish and multiple. Mosaic warts are a cluster of small warts in one area, usually on the feet and hands. Genital warts on the genital organs, which are transmitted sexually, are mentioned separately.

What a wart root is and black dots

The "root" is a colloquial term; in plantar warts, tiny black dots are visible under the hard skin; what is visible in the thickness of the skin is assessed by a doctor.

Why a wart can be uncomfortable

Warts themselves are not dangerous, but they are bothersome: some people describe them as itchy, painful, or visually inconvenient. Plantar warts hurt when walking, as if stepping on a needle.

Bleeding or a change in appearance is no longer about itching. A wart that bleeds or changes its appearance requires examination: other skin growths, including those with a less favorable course, are sometimes hidden under such a mask.

When a skin growth should be shown to a doctor

The practice is simple: show a dermatologist anything that raises questions. An examination helps distinguish a wart from similar structures, and if necessary the doctor refers the patient for further evaluation.

• any new skin growth that bothers you;
• a wart that returns after removal;
• a very large or painful wart;
• a growth that bleeds or changes appearance;
• a wart on the face or on the genital organs.

A skin growth by itself is not a reason to call an ambulance; 103 or 112 — for life-threatening conditions.

This material is for reference: it describes what this looks like and what a doctor assesses, but it does not replace a consultation — the final answer is given by an examination, not by an article.

This content is for reference and does not replace a doctor's consultation. Medical disclaimer