What’s Causing This Skin Lesion?

What are skin lesions?

A skin lesion is a part of the skin that has an abnormal growth or appearance compared to the skin around it.

Two categories of skin lesions exist: primary and secondary. Primary skin lesions are abnormal skin conditions present at birth or acquired over a person’s lifetime.

Secondary skin lesions are the result of irritated or manipulated primary skin lesions. For example, if someone scratches a mole until it bleeds, the resulting lesion, a crust, is now a secondary skin lesion.

Conditions that cause skin lesions, with pictures

Many conditions can cause different types of skin lesions. Here are 21 possible causes and types.

Warning: Graphic images ahead.

Acne

• Commonly located on the face, neck, shoulders, chest, and upper back
• Breakouts on the skin composed of blackheads, whiteheads, pimples, or deep, painful cysts and nodules
• May leave scars or darken the skin if untreated

Read full article on acne.

Cold sore

• Red, painful, fluid-filled blister that appears near the mouth and lips
• Affected area will often tingle or burn before the sore is visible
• Outbreaks may also be accompanied by mild, flu-like symptoms such as low fever, body aches, and swollen lymph nodes

Read full article on cold sores.

Herpes simplex

• The viruses HSV-1 and HSV-2 cause oral and genital lesions
• These painful blisters occur alone or in clusters and weep clear yellow fluid and then crust over
• Signs also include mild flu-like symptoms such as fever, fatigue, swollen lymph nodes, headache, body aches, and decreased appetite
• Blisters may reoccur in response to stress, mensturation, illness, or sun exposure

Read full article on herpes simplex.

Actinic keratosis

• Typically less than 2 cm, or about the size of a pencil eraser
• Thick, scaly, or crusty skin patch
• Appears on parts of the body that receive a lot of sun exposure (hands, arms, face, scalp, and neck)
• Usually pink in color but can have a brown, tan, or gray base

Read full article on actinic keratosis.

Allergic eczema

• May resemble a burn
• Often found on hands and forearms
• Skin is itchy, red, scaly, or raw
• Blisters that weep, ooze, or become crusty

Read full article on allergic eczema.

Impetigo

• Common in babies and children
• Rash is often located in the area around the mouth, chin, and nose
• Irritating rash and fluid-filled blisters that pop easily and form a honey-colored crust

Read full article on impetigo.

Contact dermatitis

• Appears hours to days after contact with an allergen
• Rash has visible borders and appears where your skin touched the irritating substance
• Skin is itchy, red, scaly, or raw
• Blisters that weep, ooze, or become crusty

Read full article on contact dermatitis.

Psoriasis

• Scaly, silvery, sharply defined skin patches
• Commonly located on the scalp, elbows, knees, and lower back
• May be itchy or asymptomatic

Read full article on psoriasis.

Chickenpox

• Clusters of itchy, red, fluid-filled blisters in various stages of healing all over the body
• Rash is accompanied by fever, body aches, sore throat, and loss of appetite
• Remains contagious until all blisters have crusted over

Read full article on chickenpox.

Shingles

• Very painful rash that may burn, tingle, or itch, even if there are no blisters present
• Rash comprising clusters of fluid-filled blisters that break easily and weep fluid
• Rash emerges in a linear stripe pattern that appears most commonly on the torso, but may occur on other parts of the body, including the face
• Rash may be accompanied by low fever, chills, headache, or fatigue

Read full article on shingles.

Sebaceous cyst

• Sebaceous cysts are found on the face, neck, or torso
• Large cysts may cause pressure and pain
• They are noncancerous and very slow growing

Read full article on sebaceous cyst.

MRSA (staph) infection

This condition is considered a medical emergency. Urgent care may be required.

• An infection caused by a type of Staphylococcus, or staph, bacteria that’s resistant to many different antibiotics
• Causes an infection when it enters through a cut or scrape on the skin
• Skin infection often looks like a spider bite, with a painful, raised, red pimple that may drain pus
• Needs to be treated with powerful antibiotics and can lead to more dangerous conditions like cellulitis or blood infection

Read full article on MRSA infection.

Cellulitis

This condition is considered a medical emergency. Urgent care may be required.

• Caused by bacteria or fungi entering through a crack or cut in the skin
• Red, painful, swollen skin with or without oozing that spreads quickly
• Hot and tender to the touch
• Fever, chills, and red streaking from the rash might be a sign of serious infection requiring medical attention

Read full article on cellulitis.

Scabies

• Symptoms may take four to six weeks to appear
• Extremely itchy rash may be pimply, made up of tiny blisters, or scaly
• Raised, white or flesh-toned lines

Read full article on scabies.

Boils

• Bacterial or fungal infection of a hair follicle or oil gland
• Can appear anywhere on the body, but are most common on the face, neck, armpit, and buttock
• Red, painful, raised bump with a yellow or white center
• May rupture and weep fluid

Read full article on boils.

Bullae

• Clear, watery, fluid-filled blister that is greater than 1 cm in size
• Can be caused by friction, contact dermatitis, and other skin disorders
• If clear liquid turns milky, there might be an infection

Read full article on bullaes.

Blister

• Characterized by watery, clear, fluid-filled area on the skin
• May be smaller than 1 cm (vesicle) or larger than 1 cm (bulla) and occur alone or in groups
• Can be found anywhere on the body

Read full article on blisters.

Nodule

• Small to medium growth that may be filled with tissue, fluid, or both
• Usually wider than a pimple and may look like a firm, smooth elevation under the skin
• Usually harmless, but may cause discomfort if it presses on other structures
• Nodules may also be located deep inside the body where you cannot see or feel them

Read full article on nodules.

Rash

This condition is considered a medical emergency. Urgent care may be required.

• Defined as a noticeable change in the color or texture of the skin
• May be caused by many things, including insect bites, allergic reactions, medication side effects, fungal skin infection, bacterial skin infection, infectious disease, or autoimmune disease
• Many rash symptoms can be managed at home, but severe rashes, especially those seen in combination with other symptoms such as fever, pain, dizziness, vomiting, or difficulty breathing, may require urgent medical treatment

Read full article on rashes.

Hives

• Itchy, raised welts that occur after exposure to an allergen
• Red, warm, and mildly painful to the touch
• Can be small, round, and ring-shaped or large and randomly shaped

Read full article on hives.

Keloids

• Symptoms occur at the site of a previous injury
• Lumpy or rigid area of skin that may be painful or itchy
• Area that is flesh-colored, pink, or red

Read full article on keloids.

Wart

• Caused by many different types of a virus called human papillomavirus (HPV)
• May be found on the skin or mucous membranes
• May occur singly or in groups
• Contagious and may be passed to others

Read full article on warts.

What causes skin lesions?

The most common cause of a skin lesion is an infection on or in the skin. One example is a wart. The wart virus is passed from one person to another through direct skin-to-skin contact. The herpes simplex virus, which causes both cold sores and genital herpes, is also passed through direct contact.

A systemic infection (an infection that occurs throughout your body), such as chickenpox or shingles, can cause skin lesions all over your body. MRSA and cellulitis are two potentially life-threatening infections that involve skin lesions.

Some skin lesions are hereditary, such as moles and freckles. Birthmarks are lesions that exist at the time of birth.

Others can be the result of an allergic reaction, such as allergic eczema and contact dermatitis. Some conditions, like poor circulation or diabetes, cause skin sensitivity that can lead to lesions.

Types of primary skin lesions

Birthmarks are primary skin lesions, as are moles, rashes, and acne. Other types include the following.

Blisters

Small blisters are also called vesicles. These are skin lesions filled with a clear fluid less than 1/2 centimeter (cm) in size. Larger vesicles are called blisters or bullae. These lesions can be the result of:

• sunburns
• steam burns
• insect bites
• friction from shoes or clothes
• viral infections

Macule

Examples of macules are freckles and flat moles. They are small spots that are typically brown, red, or white. They are usually about 1 cm in diameter.

Nodule

This is a solid, raised skin lesion. Most nodules are more than 2 cm in diameter.

Papule

A papule is a raised lesion, and most papules develop with many other papules. A patch of papules or nodules is called a plaque. Plaques are common in people with psoriasis.

Pustule

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

Rash

Rashes are lesions that cover small or large areas of skin. They can be caused by an allergic reaction. A common allergic reaction rash occurs when someone touches poison ivy.

Wheals

This is a skin lesion caused by an allergic reaction. Hives are an example of wheals.

Types of secondary skin lesions

When primary skin lesions are irritated, they can develop into secondary skin lesions. The most common secondary skin lesions include:

Crust

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

Ulcer

Ulcers are typically caused by a bacterial infection or physical trauma. They are often accompanied by poor circulation.

Scale

Scales are patches of skin cells that build up and then flake off the skin.

Scar

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

Skin atrophy occurs when areas of your skin become thin and wrinkled from overuse of topical steroids or poor circulation.

Who is at risk for skin lesions?

Some skin lesions are hereditary. People with family members who have moles or freckles are more likely to develop those two types of lesion.

People with allergies may also be more likely to develop skin lesions related to their allergy. People diagnosed with an autoimmune disease such as psoriasis will continue to be at risk for skin lesions throughout their lives.

Diagnosing skin lesions

In order to diagnose a skin lesion, a dermatologist or doctor will conduct a full physical exam. This will include observing the skin lesion and asking for a full account of all symptoms. To confirm a diagnosis, they make take skin samples, perform a biopsy of the affected area, or take a swab from the lesion to send to a lab.

Treating skin lesions

Treatment is based on the underlying cause or causes of skin lesions. A doctor will take into account the type of lesion, personal health history, and any treatments previously attempted.

Medications

First-line treatments are often topical medications to help treat the inflammation and protect the affected area. Topical medication can also provide mild symptom relief to stop pain, itching, or burning caused by the skin lesion.

If your skin lesions are the result of a systemic infection, such as shingles or chickenpox, you may be prescribed oral medications to help ease the symptoms of the disease, including skin lesions.

Surgeries

Skin lesions that are infected are typically lanced and drained to provide treatment and relief. Suspicious-looking moles that have been changing over time may need to be removed surgically.

A type of vascular birthmark called hemangioma results from malformed blood vessels. Laser surgery is often used to remove this type of birthmark.

Home care

Some skin lesions are very itchy and uncomfortable, and you may be interested in home remedies for relief.

Oatmeal baths or lotions can provide relief from itching or burning caused by certain skin lesions. If chafing is causing contact dermatitis in places where the skin rubs against itself or a piece of clothing, absorbent powders or protective balms can reduce friction and prevent additional skin lesions from developing.