Skin lesions are abnormal areas on the skin. They can be flat like freckles or raised to form a bump like a blister. Skin lesions can be localized like contact dermatitis rash or they can be generalized like chickenpox.
The color of the lesions can vary too. There are many different types of skin lesions, some are present at birth and some can appear later.
Although most are harmless and may be treated at home, some may be cancerous or serious skin conditions that require medical treatment.
This article includes descriptions of different types of skin lesions with charts and pictures of common skin lesions. It also covers their causes and treatment options.
Table of Contents
What is a lesion?
A lesion is a term used for any abnormal area or tissue in the body. A lesion can be cancerous or non-cancerous.
What are skin lesions?
A skin lesion, also known as a cutaneous lesion, is any area of skin that differs from the surrounding normal skin. This difference may be noticeable in color, texture, consistency, or surface characteristics.
Skin lesions can be divided into two types: primary and secondary skin lesions.
Primary skin lesions are the ones that appear first on healthy skin. They are a direct result of an underlying cause. These may be present at birth or may appear later in life.
Secondary skin lesions occur due to the manipulation or progression of primary lesions. For instance, as a blister heals, it may form a crusty skin lesion.
Skin conditions that cause them
Below is a list of 32 conditions that can result in various types of skin lesions, including both non-cancerous and cancerous ones.
1. Acne
Acne is of two types: non-inflammatory and inflammatory.
- Non-inflammatory acne lesions include closed comedones and open comedones (blackheads).
- Inflammatory acne lesions include can present as papules, pustules, cysts, and nodules. Cysts and nodules appear when the inflammation goes deeper into the skin. They are often painful.
It is usually seen on the face, back, and chest.
Cause
The main causes behind acne are plugging of pores with oil and dead skin cells, inflammation, and proliferation of acne-causing bacteria. Hormones can drive sebum production in teenage years leading to acne.
Treatment
The treatment depends on the type and severity of acne. The ingredients used for treatment include – salicylic acid, azelaic acid, retinoids, benzoyl peroxide, and antibiotics.
In severe cases, oral antibiotics and an oral form of vitamin A (Accutane) may be prescribed.
2. Actinic keratosis
Actinic keratosis usually presents as rough or crusty skin lesions on sun-exposed areas like the face, scalp, and neck. The color can vary – tan, pink, red, or brown.
Cause
It is a precancerous lesion that occurs due to DNA damage in the epidermal cells (usually due to sun exposure).
Treatment
It can be treated with topicals like 5- fluorouracil, imiquimod, ingenol mebutate, or diclofenac or procedures like laser, freezing, or local excision.
If left untreated, it can progress to squamous cell cancer in around 5-10% of cases.
3. Birthmarks
Birthmarks are skin lesions that are present at birth or they appear just after birth. They can be flat or raised skin lesions. The two main types are:
Vascular birthmarks that appear as red, purple, or bruise-like spots. They occur due to abnormal blood vessels. It includes salmon patches, hemangiomas, and port wine stains.
Pigmented birthmarks appear as tan or brown, raised or flat skin lesions. They occur due to the overgrowth of pigment-forming cells. The common ones are café-au-lait spots, Mongolian spots, and moles.
Cause
The exact cause behind birthmarks is not known.
Treatment
Most of these lesions are harmless and don’t require treatment. However, some may require treatment.
4. Blisters
Blisters are fluid-filled bumps on the skin. Depending on the size, they are called:
- Vesicle (less than 0.5 cm)
- Bulla (more than 0.5 cm)
Cause
Blisters can occur due to friction, pressure, burns, allergic reactions, autoimmune diseases like pemphigus, and infections like herpes.
Treatment
Blisters due to friction and pressure usually heal over time. One should not pop the blisters. The area should be kept clean and if possible covered to protect the blisters.
Autoimmune conditions like pemphigus will require prescription medications.
You should see a doctor if you notice pus or any foul-smelling discharge, fever, or extreme pain.
5. Blood spots
Blood spots occur due to bleeding into the skin. They can be classified according to their size:
- Petechiae are smaller in size (less than 2 mm)
- Purpura is larger (more than 2 mm)
- Ecchymosis (more than 10 mm).
They usually appear as flat red or purple lesions (some purpura can be raised). They do not blanch, meaning if you press them, they don’t fade.
Cause
They can occur due to various reasons: Due to abnormal or lower number of platelets, due to inflammation or injury to blood vessels, or due to disorders that affect clotting factors.
Treatment
The treatment will depend on the underlying cause It may include steroids, platelet transfusion, surgery to remove spleen, and other medications.
6. Cellulitis
Cellulitis is a bacterial infection of the skin that typically affects the lower legs. The infected area becomes red, swollen, and painful, and may present with open skin sores or lesions. Symptoms often include fever, chills, and fatigue.
Cause
Staphylococcus and streptococcus bacteria are the most common causes of cellulitis.
Whenever there is a break in the skin, these bacteria can get into the skin. The common risk factors are an injury or cut, insect bites, surgical wounds, weakened immune system, or inflammatory skin conditions like eczema.
Treatment
If diagnosed early, it can be treated with oral antibiotics. Severe cases may require intravenous antibiotics and hospitalization.
If left untreated, the infection can spread into the blood and other organs leading to serious complications.
7. Cherry angioma
Cherry angiomas are non-cancerous lesions that appear as bright red to purple papules. They are commonly seen on the chest, back, and arms and appear after the age of 30-40s.
Cause
Cherry angiomas consist of proliferating blood vessels. Why they occur is not entirely clear. Genetics, hormones, aging, and certain medications may play a role.
Treatment
They are harmless and usually don’t hurt or itch, so they don’t require treatment. However, if they bleed or for cosmetic reasons, they can be removed in a doctor’s office by procedures like freezing and lasers.
8. Chickenpox
Chickenpox is a viral infection that causes a blistering rash all over the body. The chickenpox rash typically starts as red spots on the skin, which then form into blisters.
These blisters eventually scab over, resulting in crusted lesions on the skin. Symptoms of chickenpox often include fever and fatigue.
Cause
Chickenpox is caused by the Varicella zoster virus. It is a contagious skin infection and can spread by close contact until all the lesions scab.
Treatment
The rash usually clears in 2 weeks. The treatment is symptomatic with hydration and medications to reduce fever. Antiviral medication may be prescribed for some people. It can be prevented by a chickenpox vaccine.
9. Cold sores (fever blisters)
Cold sores present as fluid-filled skin lesions, or blisters, on and around the lips, eyes, or cheeks. These blisters may ooze and eventually scab over, forming crusty spots on the skin.
One may feel a burning or itching sensation before the appearance of the bumps.
Cause
These are caused by herpes simplex virus, usually type 1. Once a person is infected, this virus stays in the body and can reactivate leading to an outbreak. The common precipitating factors include a suppressed immune system, stress, sun exposure, fatigue, or hormonal changes.
This is a contagious infection and the virus can be transferred by direct contact with the skin lesions or contaminated surfaces. One stays infectious until all the lesions heal completely.
Treatment
In a healthy individual, cold sores often heal in 1-2 weeks. Some over-the-counter remedies include:
- Balms with benzocaine: These can decrease the pain.
- Lip balms or ointments can moisturize the area.
- Abreva cream is an OTC option that has an antiviral. It can help in faster healing of sores.
Topical and oral antivirals may be prescribed in severe cases or in people with weakened immune systems.
10. Contact dermatitis
Contact dermatitis can lead to red papules, patches, or blister formation. These are usually associated with itching and localized to the area of contact.
It can be of two types:
Irritant contact dermatitis: This occurs due to contact of skin with an irritant which can lead to skin barrier disruption. The common irritants are surfactants, fragrances, essential oils, chemicals at work, etc.
Allergic contact dermatitis: This occurs when the skin comes in contact with an allergen. The common allergens are latex, poison ivy, mold, dust, animal dander, and metals like nickel.
Treatment
The symptoms can be managed with a cold compress, antihistamines, and topical steroids. One should avoid further contact with allergens or irritants.
11. Eczema
There are various types of eczema and the most common type is atopic dermatitis.
It can occur at any age although it is most often seen in children. It can lead to different types of lesions – red papules, patches, blisters, and thickening of the skin.
Cause
The exact reason behind it is not exactly clear. However, genetics, skin barrier defect, or altered skin microbiome may play some role.
Treatment
The treatment will depend on the severity of symptoms. Mild cases may benefit from barrier repair moisturizers and gentle skincare.
In some cases, topical steroids, calcineurin inhibitors, or other medications may be prescribed by your doctor.
12. Folliculitis
Folliculitis may present with red papules and pus-filled skin lesions called pustules. It occurs due to inflammation and infection of the hair follicles. The commonly involved areas are the face, arms, legs, and buttocks.
If the infection gets deeper into the hair follicle, it can lead to the formation of a boil.
Cause
Folliculitis is of various types and bacterial folliculitis is the most common. Most often, it is caused by the bacteria Staphylococcus aureus.
Risk factors for developing folliculitis include:
- A skin injury.
- Heavy sweating.
- Contaminated tubs.
- Underlying medical conditions like diabetes.
Treatment
Antibacterial washes may be beneficial, although most mild cases may resolve on their own. Topical antibiotic mupirocin and/or oral antibiotics may be required in some cases.
13. Freckles
Freckles are flat skin lesions (macular lesions) with extra pigment which can be red, tan, yellow, or brown in color. They are two types:
Ephelides: These are the freckles that appear in childhood. These are small, red to brown in color, and do not have well-defined borders. They are frequently seen on the face, arms, neck, and chest. They usually fade in winter.
Solar lentigines (Age spots, sunspots, or liver spots): These appear as flat tan or brown skin lesions on the sun-exposed areas like the face and back of hands in older individuals. These have a well-defined border and these do not fade in winter.
Treatment
Freckles are usually harmless and don’t need treatment unless for cosmetic reasons or if they look suspicious. They can be lightened by retinoids, lasers, chemical peels, or dermabrasion.
14. Hives
Hives called urticaria can lead to the formation of wheals. These are oval, round, or irregularly shaped itchy skin lesions. They can be skin-colored, pink, red, or tan in color. If you press them, they become pale.
They usually disappear in a short time. However, sometimes they can last longer (more than 6 weeks) and are called chronic hives.
Cause
These often occur due to the release of histamine from the immune cells. This can occur in response to certain foods, medications, infections, pollen, dust, etc.
Treatment
Over-the-counter antihistamines may reduce the symptoms. One should avoid the triggering factor.
In some cases, hives may be associated with swelling of the face, throat, and other parts of the body leading to difficulty in breathing, chest tightness, dizziness, and confusion. This is called anaphylaxis.
If one has any of these symptoms, one should go to the hospital immediately.
15. Impetigo
Impetigo is a contagious bacterial infection that can lead to red bumps which form blisters. These can burst leading to sores, red patches, over which honey-colored crust forms.
It is usually seen in children and involves the area around the mouth and nose.
Cause
It occurs due to infection by the bacteria Staphylococcus aureus. One can acquire it by direct contact with the lesions or contaminated surfaces.
Treatment
It is treated with mupirocin which is a topical antibiotic. Oral antibiotics may be required in a few cases.
16. Insect bites
Insect bites and stings can lead to itchy red bumps or papules on the skin. In some cases, the bumps may form vesicles.
Cause
These occur due to the skin’s reaction to the secretion of insects or their stings. The common offenders are fleas, bed bugs, mosquitos, ants, flies, and bee stings.
Treatment
They usually clear on their own and do not require treatment. Antihistamines may help in reducing itching.
17. Keloid
Keloid presents as raised skin lesions that are skin-colored, red, or purplish in color. They are soft and rubbery in consistency. They may be associated with itching.
These are commonly seen on the pre-sternal areas on the chest, upper back, shoulders, or cheeks.
Cause
The formation of keloids is triggered by any skin injury. They occur due to the formation of excess collagen during the healing process.
Certain factors increase the risk of keloid formation. These include darker skin tone, age under 30 years, and family history of keloids.
Treatment
They can be difficult to treat and may grow back. The treatment options include silicone or pressure dressing, steroid injections, laser, freezing, or surgical excision.
18. Keratosis pilaris
Keratosis pilaris can lead to tiny red raised skin lesions (papules) with rough surfaces that can feel like sandpaper. These usually appear on the cheeks, upper arms, thighs, or buttocks.
It is common in children and adolescents and clear by the age of 20-30s.
Cause
It is thought to occur due to blockage of the hair follicles with a protein called keratin. Keratin is part of the outer layer of our skin.
Genetics and atopic dermatitis may play some role in causing it, although the exact cause is not clear.
Treatment
It is harmless and goes away on its own. Some skincare ingredients may help in improving their appearance like retinoids, urea, lactic acid, or glycolic acid. Moisturizers can reduce the rough texture.
19. Melasma
Melasma is a common skin condition that leads to symmetrical flat dark patches on the face. They are usually located on the cheeks, nose, forehead, chin, and upper lip.
They can be any shade of brown, gray, or bluish in color. It often affects women between the ages of 20 and 40, especially during pregnancy.
Cause
Hormones and sun exposure are one of the main causes behind it. These can lead to the overproduction of melanin pigment leading to dark patches on the face.
Treatment
It is harmless but can be a cosmetic issue. It can be resistant to treatment.
The treatment options include topicals like hydroquinone, retinoids, kojic acid, arbutin, azelaic acid or niacinamide. In some cases, procedures like chemical peels and lasers may improve them. Adequate sun protection is important to treat and prevent them.
20. Milia
Milia are small pearly white bumps or cysts that are commonly seen on the face (especially on the cheeks, nose, and under the eyes). They are often seen in infants but they can occur at any age.
Cause
These occur due to the trapping of dead skin cells under the skin. These cells can become hard resulting in these white cysts.
Several factors are associated with their formation:
- Damage to the skin barrier or skin injury.
- Sun exposure.
- Long-term use of steroids.
- Genetics.
- Autoimmune skin conditions.
- Heavy and occlusive cosmetics.
- Procedures like microdermabrasion and laser resurfacing.
Treatment
They are harmless and usually go away on their own in a few weeks or months. Topicals like salicylic acid and retinoids like retinol can help in clearing them.
If they don’t help, prescription-strength retinoids like tretinoin or procedures done in a doctor’s office like deroofing, freezing, chemical peels and laser ablation may resolve them.
21. Moles
Moles are skin growths that consist of melanocytes, the cells that make melanin pigment and give color to our skin. They can be present at birth or can be acquired during a lifetime.
They present as round to oval flat or raised skin lesions – macules, papules, or nodules.
Treatment
They are usually harmless and do not require any treatment. If needed, your doctor can remove them by shaving or excision.
One should regularly examine moles for any suspicious changes in size, color, shape, or border. These may be signs of melanoma which is a type of skin cancer.
22. Psoriasis
Psoriasis is a chronic inflammatory skin condition and is of various types. Plaque psoriasis is the most common type. It starts as red papules or bumps that come together to form red raised skin lesions – plaques.
They are covered with white or silvery scales. If the scales are removed, it leads to a pinpoint bleeding spot, this is called the Auspitz sign.
The commonly affected areas are elbows, knees, scalp, and trunk. One may also see changes in nails and joints.
Cause
The exact cause is not known. However, our immune system, genetics, and environmental factors may play a role in it.
Treatment
The treatment depends on the severity of the disease. It includes:
- Topicals containing coal tar or salicylic acid.
- Topical or oral steroids.
- Immunosuppressants.
- Vitamin D or A derivatives.
- Phototherapy.
23. Ringworm
Ringworm is a contagious fungal infection of the skin, hair, and nails. Depending on the part of the body involved it can have different names. The ringworm of the foot is called tinea pedis, ringworm of the hands is called tinea manuum, and ringworm of the body is called tinea corporis.
The symptoms may vary depending on the area involved. In general, the ringworm presents with a red circular rash that has a clear center giving it the appearance of a ring.
The periphery is raised and, in some cases, small red papules or blisters may be seen.
Cause
The group of fungi that cause ringworm are called dermatophytes. Ringworm can spread by direct contact with the lesions, infected animals, contaminated surfaces, or soil.
Treatment
Mild cases of ringworm of the skin may be treated with over-the-counter antifungal products. In severe cases and ringworm of the beard, scalp, and nails, prescription medications and oral antifungals may be prescribed.
24. Rosacea
Rosacea is a very common skin condition characterized by redness and flushing. It is of 4 types:
- Erythematotelangiectatic type is characterized by persistent redness. Broken capillaries may be seen in the background.
- Papulopustular type presents with red papules, pustules, and redness. These usually appear on the cheeks, chin, and forehead
- Phymatous type present with skin thickening.
- Ocular rosacea affects the eyes.
Cause
The exact cause is not clear. Genetics, environmental factors, the immune system, and Demodex mites may play some role in it.
It can be precipitated by factors like spicy food, alcohol, stress, exercise, and extreme temperatures.
Treatment
It is treated with topicals like metronidazole, azelaic acid, and ivermectin. Oral antibiotics may be prescribed in some cases. Broken capillaries or telangiectasia and persistent redness may be improved with laser or intense pulsed light therapy.
25. Scabies
Scabies can present with itchy red lesions on the skin. These may form blisters. Intense itching can lead to open sores and secondary infection. The location of skin lesions may vary depending on the age.
- In young children, the commonly involved areas are the head and neck, palms, and soles.
- In adults, it usually involves skin folds, inside of the elbow or wrist, between the fingers, nipple, groin, or waist.
Cause
It is caused by a mite called Sarcoptes scabiei. It is very contagious and one can get it by coming in close contact with someone who has scabies or their personal items.
Treatment
Scabies does not resolve on its own and requires treatment. The treatment options include topicals with – permethrin (5%), benzyl benzoate (25%), crotamiton (10%), or sulfur (5 to 10%). Oral ivermectin may be needed in some cases.
26. Seborrheic dermatitis
Seborrheic dermatitis presents with red greasy patches covered with thick yellow scales, commonly on the face – on the sides of the nose and between eyebrows, scalp, ears, chest, and back.
These are usually associated with itching. In people with darker skin tones, it may present as dark reddish brown or hypopigmented spots.
Cause
The exact cause is not clear; however, Malassezia (a fungus), excessive oiliness, and skin barrier dysfunction may play a role in it. It is also associated with certain medications and neurological diseases.
Treatment
Mild cases may improve with the use of anti-dandruff shampoos with zinc pyrithione, ketoconazole, selenium sulfide, or salicylic acid.
Severe cases may require prescription topical antifungals, steroids, or oral medications.
27. Seborrheic keratosis
Seborrheic keratosis (also known as skin barnacles) is a non-cancerous skin growth that leads to brown, tan, or black flat or raised lesions, commonly on the face, chest, back, or neck. They have a waxy and stuck-on appearance.
Cause
The exact cause of why they occur is not known, however, genetics may play some role.
Treatment
They are harmless but may become irritated. If needed, they can be removed in a doctor’s office by freezing, shave excision, curettage, or lasers.
28. Shingles
Shingles, also called herpes zoster, is a viral infection that results in a painful blister rash. The condition typically begins with burning and itching sensations, followed by the appearance of red bumps.
These bumps subsequently form blisters, which eventually turn into crusts and scabs. Accompanying symptoms may include fever and fatigue.
The rash usually affects one side of the body, such as the left arm or left torso.
Cause
It occurs due to a type of herpes virus – Varicella-zoster virus. This is the same virus that causes chickenpox.
Once a person gets chickenpox, this virus stays in the body. It can reactivate later in life leading to shingles.
An outbreak can occur due to certain medications, stress, a weakened immune system, or underlying medical conditions like HIV, diabetes, or cancer.
The virus that causes shingles can spread to others who never had chickenpox or vaccination against it. In such people, it can lead to chicken pox and not shingles.
Treatment
Antiviral medications can help in faster healing and prevention of complications like persistent pain even after shingles are completely healed (this is called postherpetic neuralgia).
Medications to reduce pain like gabapentin or amitriptyline, may also be prescribed by your doctor.
Shingles can be prevented by the Shingrix vaccine which is considered 90% effective.
29. Skin cyst
There are several types of cysts, with epidermoid cysts (also known as epidermal inclusion cysts) being among the most common.
An epidermal cyst presents as a white, yellow, or skin-colored lesion, usually occurring on the face, neck, or back. It may have a punctum. These cysts can develop due to injury or blockage of the hair follicle. These are lined by squamous epithelium and filled with keratin.
Treatment
Skin cysts are usually harmless and do not require treatment. However, if a cyst is large or needs to be removed for cosmetic reasons, surgical removal is an option. It’s important to remove the entire cyst wall to prevent recurrence.
30. Skin tags
Skin tags are non-cancerous lesions that may appear in the skin folds. They are soft with smooth surfaces attached to the skin with a fine stalk. They are usually skin-colored or slightly darker than skin.
They are commonly seen on the neck, eyelids, armpits, groin, under the breast, and genitalia.
Cause
It is thought that skin tags may occur due to frequent skin irritation or a normal aging process. Some risk factors for developing skin tags are genetics, rubbing of the skin, being overweight, hormonal changes, or diabetes.
Treatment
Skin tags are harmless and usually do not require treatment. If needed, they can be removed by freezing, ligation to cut off blood supply, shaving, or cutting it off with sterile surgical instruments.
31. Warts
Warts are small raised skin lesions that are usually skin-colored. The different types of warts are:
- Common warts
- Flat warts
- Filiform warts
- Plantar warts
- Genital warts
- Periungual warts
Cause
These are caused by a virus called HPV or human papillomavirus. Warts are contagious and the virus usually spreads by sexual contact.
However, skin-to-skin contact can also lead to warts. It can also be acquired by contaminated surfaces or sharing common things like towels.
Any type of skin barrier impairment or injury can make one more prone to warts (like shaving, or cutting, or chronic skin conditions like eczema).
Treatment
There are several over-the-counter topicals that contain salicylic acid and can be used for warts. However, be careful when using them on your face or areas with sensitive skin.
In addition, if you are not sure that you have warts, it’s best to check with a doctor, as many other skin growths including cancer can be mistaken for warts.
If over-the-counter treatment options don’t work, your doctor can remove them by freezing, curettage, excision, or lasers.
32. Skin cancer
A skin lesion is rarely due to skin cancer. The three main types of skin cancer are:
Basal cell carcinoma can present as a shiny or waxy papule or nodule, a flat scaly patch, or a non-healing sore or ulcer. The color may vary – white, skin-colored, pink, red, or brown.
Squamous cell carcinoma: It may present as red nodules, a non-healing ulcer, or an open sore, rough patch, or wart-like growth.
Melanoma can present as an irregular flat lesion or raised papule or nodule. The border is usually asymmetrical with uneven color distribution.
Cause & Treatment
Sun exposure is considered the main factor causing skin cancer. The treatment will depend on the type of cancer, size, depth of invasion, and the spread of the cancerous cells in the body. It may include surgical excision of the lesion, lymph node removal, or chemotherapy.
A skin lesion that looks suspicious should be examined by a doctor for early diagnosis and treatment of skin cancer.
Causes
There are many different skin lesions and the underlying cause of each will vary. Some of the possible causes include:
- Local infection in an area like warts.
- Systemic infection like chickenpox.
- Genetics like ichthyosis.
- Allergies like hives.
- Irritant like contact dermatitis.
- Any injury.
- Medical conditions like diabetes.
- Drugs.
Some lesions do not have a clear cause behind them.
Primary skin lesions
Primary skin lesions can be present at birth, as in the case of hemangiomas or moles, or they can develop later in life, like acne or melasma, among others.
Some key factors help in identifying these lesions: whether the skin lesion is flat or raised, the size of the lesion, and the consistency or their contents.
Additionally, the color and distribution of the skin lesion can further help in identifying different types of skin lesions.
The various types of primary skin lesions are shown in the chart below.
- Macule: A flat circumscribed skin lesion with a different color (an area of discoloration) and less than 1 cm in size.
- Patch: A flat skin lesion with a different color and greater than 1 cm.
- Papule: A circumscribed, elevated, and firm lesion less than 1 cm in size. It may be of different colors.
- Plaque: A bigger circumscribed, elevated, solid lesion greater than 1 cm in size.
- Pustule: A circumscribed, elevated lesion filled with pus, usually less than 1 cm in size. These may be white or yellow.
- Vesicle: A circumscribed, elevated, lesion filled with fluid and less than 0.5 cm in size.
- Bulla: A circumscribed, elevated, lesion filled with fluid and greater than 0.5 cm in size
- Nodule: A firm skin lesion that extends into deeper layers of skin (the dermis or subcutaneous tissue). The surface may be flat or form a raised bump. They are usually more than 1 cm in size.
- Tumor: A firm lesion that is usually greater than 2 cm in size.
- Cyst: A cyst is a sac or cavity filled with air, fluid, or semisolid material.
- Wheal: It is an oval, round, or irregular solid, elevated skin lesion. It occurs due to swelling in the dermis. They usually last for a short time.
- Blood spots: They are the result of bleeding into the skin. Different names are used depending on the size: petechiae < 2 mm, purpura 2-10 mm, and ecchymosis >10 mm.
Secondary skin lesions
Secondary skin lesions can develop from the primary skin lesions like chronic eczema can lead to lichenification.
The various types of secondary skin lesions are shown in the chart below.
- Skin atrophy: The skin becomes thin and wrinkled. It can occur due to topical steroid use, steroid injection, aging, inflammatory skin conditions, or poor circulation.
- Lichenification: Thickening of the skin with prominent skin markings due to repeated rubbing.
- Excoriation: Straight scratches on the skin that lead to loss of the top layer of skin.
- Crust: A crust forms from the dried exudate, which can be blood, serum, or pus, overlying injured skin, or an irritated skin lesion.
- Erosion: Loss of the top layer of skin called epidermis. The surface is moist and it usually heals without leaving any scar.
- Ulcer: It occurs due to full-thickness loss of the epidermis along with damage to the dermis. It may leave behind scars.
- Fissure: Linear breaks into the skin extending to the dermis (the layer beneath the epidermis). They are usually painful and can occur due to excessive dryness of the skin.
- Scale: Scales appear as white flakes due to increased cell turnover or accumulation of dead skin cells due to abnormal exfoliation.
- Scar: Scars are formed due to the replacement of normal tissue with fibrous tissue. Types of scars include atrophic, hypertrophic, keloid, or contracture.
Benign vs Malignant
Benign skin lesions
Benign skin lesions are abnormal skin growths that are non-cancerous. They often grow slowly and are much more common. They do not spread in the body.
Benign skin lesions usually do not require treatment unless they cause symptoms. Some examples include moles, skin tags, lipoma, and cherry angioma.
Malignant skin lesions
Skin lesions that are malignant are skin cancer. They usually grow quickly and the cancerous cells can invade the surrounding tissues and spread in the body.
Malignant skin lesions require treatment. The treatment will depend on the type and stage of the cancer. Some examples include squamous cell carcinoma, basal cell carcinoma, and melanoma.
Diagnosis
Your doctor may diagnose a skin lesion based on the physical examination. They may use instruments like dermatoscope for better examination of the skin lesion.
They also take a complete medical history of your health, any allergies, current medications, or family history.
In some cases, they may do additional testing. These may include:
- Allergy test.
- Culture if an infectious cause is suspected.
- Biopsy of the skin lesion.
Treatment
Not every skin lesion requires treatment. Lesions like cherry angiomas, skin tags, cysts, moles, etc. are usually harmless and a person may choose to get treatment if they are a cosmetic issue or cause any symptoms.
The treatment of a skin lesion is based on the underlying cause and may include the following options.
1. Topical medications
There are various types of topical medications. They can help in treating skin lesions by different actions like reduction in inflammation or itching, treating an infection, decreasing melanin pigment formation, and so on.
2. Oral medications
In some cases, topical medications may not be enough or a person may have an underlying medical condition that requires oral medications.
3. Removal
Lesions that are cancerous, such as skin cancer, usually need to be removed surgically. Any suspicious skin lesion may also be excised. In some cases, lesions, like cysts, might be removed for cosmetic reasons.
In addition to surgery, several other procedures may be used to remove skin lesions. These include:
- Freezing
- Lasers
- Electrocautery
Key points
Skin lesions refer to any area which is different from the rest of the skin. Primary skin lesions appear first and secondary lesions appear as the disease progresses or when the primary skin lesion is traumatized.
Factors like whether the lesion is flat or raised, size, or consistency may help in defining these skin lesions.
Most lesions like acne, rashes, allergic reaction, or non-cancerous growths, are harmless. However, some lesions can be serious like skin cancer or untreated cellulitis.
You should see a doctor if you are not sure what is causing your skin lesions or you notice any change in your lesions like an increase in size, change in color, irregular border, pus or foul-smelling discharge, extreme pain, or systemic symptoms like fever and chills.
Read more: Papule vs macule
References
- Hess, Cathy Thomas BSN, RN, CWOCN. Identifying Primary and Secondary Lesions. Advances in Skin & Wound Care 25(7):p 336, July 2012. | DOI: 10.1097/01.ASW.0000416010.08584.18
- Poonawalla T, et al. (2008). Primary lesions. Department of Dermatology, University of Texas Medical Branch. Core Concepts of Pediatrics.
- Benedetti J (2001). Description of Skin Lesions. Merck Manuals.
- Cellulitis. CDC.
Disclaimer: This blog post is for information purposes only and does not replace medical advice.