What causes skin lesions?

Our skin is our protection from the world around us. It acts as an adaptable barrier from potential bacteria and other threats to our health. But sometimes our skin is compromised and lesions form. When this happens it can be worrying and disconcerting. We may wonder: what is this new mark on my skin? Where did it come from? And why? Below, we address some of these concerns and cover the basics of skin lesions, helping you understand what yours could be and how it got there.

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What is a skin lesion?

A skin lesion is a broad term that refers to any abnormality in the character of your skin. The medical dictionary defines a skin lesion as “a superficial growth or patch of the skin that does not resemble the area surrounding it.” A skin lesion can be a rash, mole, wart, cyst, blister, bump, discoloration and other changes that you may notice on your skin. A skin lesion can be a result of a simple scrape or cut or as serious as a pre-cancerous mole or mark. While the spectrum of lesions ranges greatly, there are some general categories you can use to identify yours.

What types of skin lesions are there?

There are two types of skin lesions: primary and secondary. Primary skin lesions are changes in color or texture that are generally present at birth or acquired over time, like a birthmark or age spot. Secondary skin lesions are a progression of primary skin lesions. They are changes to the original lesion that result from a natural evolution of the lesion or a person scratching or aggravating the lesion.

The common types of primary skin lesions are:

·  Blisters: also called vesicles; these are small lesions filled with a clear fluid. Vesicles can be the result of sunburns, steam burns, insect bites, friction from shoes or clothes and viral infections.

·  Macule: freckles and flat moles. Macules are small spots that are typically brown, red or white. They are usually about one centimeter in diameter.

·  Nodule: a solid, raised skin lesion. Most nodules are more than two centimeters in diameter.

·  Papule: a lesion that is rough in texture. Most papules develop with many other papules. A patch of papules is called a plaque. Plaques are common in people with psoriasis.

·  Pustule: small lesions filled with pus. They are typically the result of acne, boils or impetigo.

·  Rash: lesions that cover small or large areas of skin. They can be caused by an allergic reaction. A common allergic reaction rash occurs when a person touches poison ivy.

·  Wheals: skin lesions caused by an allergic reaction. Hives are an example of wheals.

The common types of secondary skin lesions are:

·  Crusts: a crust, or a scab, is created when dried blood forms over a scratched and irritated skin lesion.

·  Ulcers: typically caused by a bacterial infection or physical trauma.

·  Scale: patches of skin cells that build up and then fall off the skin.

·  Scars: some scratches, cuts, and scrapes will leave scars that are not replaced with healthy, normal skin. Instead, the skin returns as a thick, raised scar. This scar is called a keloid.

·  Skin atrophy: areas of your skin that become thin and wrinkled from over use of topical steroids or antibiotic creams. 

Source: Healthline

So what causes skin lesions?

The causes of skin lesions range widely depending on the specific type of lesion you have. The most common cause of skin lesions is infection of the skin by bacteria, viruses, fungi or parasites transferred by touch or through the air. Warts and chicken pox are some examples of this. Other types of lesions can be caused by allergic sensitivities or health conditions such as diabetes or poor circulation. Skin lesions can also be inherited at birth or a result of genetic predispositions. For example, some people are more likely to develop moles and freckles than others.

You should consult your doctor immediately if you notice any unidentifiable skin lesions on your skin. A doctor will examine the lesion, looking for distinguishing characteristics and consulting your past medical history. They will often take a scrape or swab of the lesion to examine the potential cause of infection.

When to worry-cancerous lesions

Cancerous lesions often appear in the form of a mole. Understanding the difference between a normal mole and a potentially cancerous mole is key to catching melanoma and other skin cancers early.

A normal or common mole usually has:

· neat edges,
· a smooth or dome-like shape,
· is around ¼ inch (6 mm) in diameter,
· and stays the same shape, size or color over time.

It’s important to take a quick inventory of the moles on your body so that you can recognize any changes that may occur over time. Understanding what’s normal for your body is the best way to catch early skin cancer symptoms.

Warning signs that it may be cancerous

Look for these indicators that your mole or lesion may be cancerous:

· A change in size (getting larger)
· A change in shape (especially with irregular edges)
· A change in color (especially getting darker or exhibiting multiple shades)
· A loss of symmetry (common moles will be perfectly round or oval and are usually symmetrical)
· Itchiness, pain or bleeding (maybe even forming a scab)
· Crustiness
· Inflammation
· Exhibiting three different shades of brown or black
· A change in elevation (thickening or raising of a flat mole)

Consult our malignant melanoma pictures to gain an understanding of what pre-cancerous and cancerous moles can look like. If you notice any of these symptoms, contact a doctor to have your mole examined.

Keep tabs on your moles over time and check to see if they are at risk for cancer by downloading SkinVision. It’s a free and easy tool for gaining some peace of mind and taking control of your health.

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