What Is Erythema?

Erythema is seen in almost every skin rash. These are often the result of a triggering event, such as using a particular drug, or having an underlying disease or infection. It can also be seen in blushing and with exercise, excess pressure, friction, ill-fitting clothing, massage, and sunburn.

Erythema refers to redness of the skin. It occurs when the blood capillaries (the smallest blood vessels in the body) closest to the surface of the skin are congested and dilated (widened). This can be due to inflammation or injury. It can appear anywhere on the body and will show up in various patterns and colors.

In addition to erythema being seen in most rashes, other conditions carry the word erythema in their names. Their causes, symptoms, and treatment differ. Some types of erythema are mild and will clear up on their own. Others will need medication or urgent medical attention. 

This article will discuss conditions with erythema in their names, their symptoms and causes, and how these different types are treated.

Types of Erythema 

Different conditions have erythema as part of their name. Each is unique its in symptoms and causes. 

Erythemic Skin Caused by Psoriasis

Psoriasis is an inflammatory skin disease that causes skin cells to multiply quicker than normal, leading to skin cell buildup in the form of bumpy red patches covered with white scales (psoriasis plaques). Different types of psoriasis lead to erythemic skin, including plaque psoriasis and a rare type called erythrodermic psoriasis.

Plaque Psoriasis

Plaque psoriasis is the most common type of psoriasis. It is known for causing raised, inflamed, and scaly patches of skin that can be itchy and painful. Plaque psoriasis can appear on any body area, but is most often seen on the elbows, knees, lower back, and scalp.

In people with fair skin, the plaques will often appear as raised, red, and patchy with silvery-white scales. In people of color, those plaques might appear darker, thicker, and purplish, grayish, or darker brown.

Erythrodermic Psoriasis

Erythrodermic psoriasis is the least common type of psoriasis and the most severe. It affects the skin across the entire body and can be life-threatening. 

It most often affects people living with severe and unstable plaque psoriasis. It has also been linked to another rare psoriasis type called pustular psoriasis.

Symptoms of pustular psoriasis include white, pus-filled, painful bumps (pustules), along with redness and discoloration of the skin. The pustules are not contagious and are the result of inflammation. 

The severe damage to the skin caused by erythrodermic psoriasis puts the body at risk for severe complications. These might include: 

• Bacterial infections, including pneumonia and sepsis
• Congestive heart failure related to heart rate increases and swelling
• Severe illness from protein and fluid loss
• Excessive swelling from fluid retention

Erythema Multiforme

Erythema multiforme (EM) is a common skin reaction triggered by an infection or certain medications. It is often mild and will go away on its own. According to the National Organization of Rare Disorders (NORD), the name is applied to a group of hypersensitivity orders that affect mainly children and young adults.

EM mainly causes “symmetric red, patchy lesions” that mostly appear on the arms and legs. Specific causes of EM are known, but the condition seems to occur with the herpes simplex virus. 

Other cases of EM are related to infectious organisms, including Mycoplasma pneumoniae (a cause of walking pneumonia) and fungal infections. According to NORD, more than half of the cases of EM are the result of a drug reaction, including reactions to “anticonvulsants, sulfonamides, nonsteroidal anti-inflammatory drugs, and other antibiotics.”

Additional symptoms of EM include:

• Blisters on the palms of the hands and soles of the treat
• Flat, round “red target” rashes (dark circles that have a purple gray center)
• Itching
• Fatigue
• Joint pain
• Fever 

Erythema Nodosum

Erythema nodosum is a type of skin inflammation that appears on the shins—the larger bone areas in the front of your lower legs. It causes tender, red bumps. 

Additional symptoms of erythema nodosum are fever, joint pain, and enlarged lymph nodes in the chest. Up to 55% of erythema nodosum cases have no clear or identifiable cause. There are also instances where erythema nodosum is the result of an infection, drug reaction, or a symptom of another disease.

Medication reactions linked to erythema nodosum include antibiotics that contain sulfa and penicillin, bromides, iodides, and oral contraceptives.

 Health conditions believed to be linked to erythema nodosum include:

• Strep infections
• Sarcoidosis: Inflammation of multiple organs, but most frequently the lungs and lymph glands
• Coccidioidomycosis: A fungal infection of the lungs and upper respiratory tract
• Histoplasmosis: A fungal pulmonary infection
• Psittacosis: A bacterial disease which in humans causes mild, non-specific flu-like symptoms
• Ulcerative colitis or Crohn’s disease
• Cancer

Treatment for erythema nodosum is aimed at the underlying cause, but it is generally self-limiting and will resolve within one to six weeks. After the skin symptoms are gone, the skin might appear bruised or there might be a chronic indentation of the skin that was affected.

Erythema nodosum can be chronic and result in occasional recurrences, with or without an underlying cause.

Erythema Marginatum

Erythema marginatum is a skin rash that appears on the trunk and the limbs. The rash appears round, has a pink center, and is surrounded by a raise red outline. It can also appear in rings or have irregular and larger shapes. 

Erythema marginatum is extremely rare. It is not a skin condition, but rather a symptom of an underlying condition.

Conditions linked to erythema marginatum include:

• Rheumatic fever: An inflammatory disease that can affect the heart, joints, brain, and skin
• Hereditary angioedema: A disorder characterized by recurrent episodes of severe swelling

Erythema marginatum is often self-limiting and will recur sporadically or persist for a few days until the underlying condition becomes managed or resolved.

Erythema Toxicum

Despite its name, erythema toxicum is a harmless and very common rash many newborns develop. These infants are otherwise healthy and don’t have any systemic (whole-body) symptoms. Babies are usually not bothered by the rash.

Most of the time, the rash resolves within five to 10 days. Recurrences of the rash are uncommon, but if they do occur, they are mild and will disappear by the sixth week of life. 

The erythema toxicum rash appears as a combination of flat patches. Some infants may experience tiny bumps, some of which are pus filled. Patches and bumps will appear on the face, trunk, arms, and legs. The palms of the hands and soles of the feet are usually not affected. 

It is unknown what causes erythema toxicum. Risk factors might include higher birth weight, greater gestational age, higher maternal age, and vaginal delivery.

Fifth Disease 

Fifth disease, also known as erythema infectiosum, is a common viral infection in school-age children. It can also affect adults and people who are pregnant. Fifth disease is caused by parvovirus B19, a virus that “spreads through direct contact with fluids and mucus from the nose or mouth of an infected person.”

It is characterized by a red rash on the cheek that appears like a “slapped cheek.” After the appearance of the slapped cheek, the rash starts to spread to the trunk, arms, and legs. It can last up to three weeks.

Outbreaks of fifth disease are common in late winter and early spring. It can affect up to 60% of children who are considered vulnerable. Fortunately, it tends to be a mild illness, and most people who have it don’t always realize it.

Because the disease is caused by a virus, there is no medication to treat it and it often clears up on its own. If the rash is itchy, a doctor can prescribe medicine to ease discomfort. Fifth disease can be monitored in children who have weakened immune systems.

Palmar Erythema 

Palmar erythema is an extremely rare skin condition that causes the palms of the hands to become red. It is sometimes heredity, but it can also be caused by another health condition. Also called Lane’s disease, it is rarely harmful.

The redness caused by palmar erythema affects both hands. It causes the palms to be warm, but it is neither itchy nor painful. The redness only affects the hands and doesn’t extend into the fingers, although some people have fingertip and nail bed redness.

A similar condition, plantar erythema, affects the soles of the feet in the same way palmar erythema affects the hands.

The cause of redness in palmar erythema is dilated capillaries. The severity of the redness depends on how severe the underlying disease is. Primary palmar erythema is sometimes heredity. It might also be the result of pregnancy or hormone issues. 

Conditions linked to palmar erythema (secondary) include: 

• Liver disease
• Cancer
• Endocrine diseases
• Autoimmune diseases
• Infections

Erythema Chronicum Migrans 

Erythema chronicum migrans will cause circular bulls-eye rashes. These rashes are frequently seen in people with early-stage Lyme disease. The rashes can appear quite large and can become five centimeters or greater (two or more inches) in size. 

Localized rashes in Lyme disease will appear three to 30 days after an infected tick bite. That may disappear on its own over days or weeks.

The skin area affected may feel warm to the touch, but erythema chronicum migrans is not painful or itchy. Because it is a sign of Lyme disease, a person with these rashes might experience additional symptoms, including fever and chills, headache, swollen lymph nodes, and joint and muscle pain.

Erythema Ab Igne

Erythema ab igne (EAI) is a skin condition resulting from long-term exposure to heat. It causes a fishnet-like pattern of hyperpigmentation (skin discoloration). These skin lesions are usually asymptomatic (causing no symptoms), but some people might experience pain, burning, and itching. 

EAI was historically seen in certain professions, including bakers and metalworkers. These days, it is rarely seen except in cases where someone has been repeatedly exposed to an infrared-type radiation source, such as from a space heater or heating pad. 

Treatment for erythema ab igne starts with discontinuing contact with the source of the rash. If symptoms are severe and include pain and itch, topical treatments might be prescribed. 

A healthcare professional will also want to look for other sources of symptoms—such as different types of skin cancers—if discontinuation of the heart source and topical treatments don’t help to resolve symptoms.

Erythema Annulare Centrifugum

Erythema annulare centrifugum (EAC) is a rare skin rash that appears as small bumps spreading out from a central area. These bumps appear in a ring-like pattern and may spread into different-shaped rashes. They usually appear on the thighs and legs, but can also occur on the trunk, buttocks, arms, or face.

The EAC skin rash is otherwise asymptomatic, although some people experience itching. EAC isn’t linked to age, race, or gender. It often appears for no reason and resolves on its own. 

EAC can also be a sign of an underlying problem or a reaction to a food, drug, or bug bite. Diseases linked to EAC include health conditions like lupus or sarcoidosis and different kinds of infections. It is rarely linked to cancer. 

EAC usually clears on its own when there is no underlying condition. It might take weeks or months, and it might even recur over months and years. There is no proven treatment, although doctors prescribe topical steroids to manage itching. Other treatments might include oral antibiotics, hyaluronic acid, and calcipotriol, a topical vitamin D derivative. 

If there is an underlying condition causing EAC, then treating that condition should help to resolve the skin rash. For infections, the rash should clear up once the infection clears. 

Keratolytic Winter Erythema 

Keratolytic winter erythema (KWE) is a rare inherited autosomal dominant skin disease that causes redness and peeling of the skin on the palms and the soles. Its onset and severity are linked to the winter months.

KWE is sometimes called Oudtshoorn skin or Oudtshoorn disease. It gets its name from the town of Oudtshoorn in the Western Cape province of South Africa, where it was first described in 1977. 

KWE rash causes the skin to appear a patchy red. The skin of the palms and soles appears thickened, and there might be dry blisters and peeling. The shedding of skin comes out in thick peels.

Some people with KWE might also experience large circular red patches on the arms and legs. These slowly expand and cause a “trailing edge of peeling.” Additional symptoms of KWE might include itching, excessive sweating (all over or just affecting the palms and soles), and a strong unpleasant odor. 

KWE is an inherited condition that affects males and females equally. It is treated mainly with systemic steroids (anti-inflammatory agents). Other treatments include medicines to help control sweating and itching. 

Other Kinds of Erythema

There are numerous types of erythema in addition to those described. They include erythema induratum secondary to TB, erythema elevatum diutinum, and erythema gyratum repens:

• Erythema induratum secondary to TB results from a tuberculid skin eruption, a group of skin conditions linked to underlying or silent tuberculosis.
• Erythema elevatum diutinum is a rare necrotizing vasculitis that causes red, purple, brown, or yellow papules, plaques, or nodules. These usually appear on the back of the hands and extensor surfaces (areas of skin on the outside of joints), and on the buttocks.
• Erythema gyratum repens is rapidly moving and a marker of underlying cancer. It is common in people with lung cancer.

Erythema Symptoms

The symptoms of erythema are dependent on the condition causing the skin redness. The redness can appear anywhere on the body in different patterns and varying colors, including red, purple, or brown. Certain types of erythema might cause blisters that burst and painful sores. 

Some underlying causes of erythema are harmless and limited to skin symptoms. Outlined below are symptoms for erythema that cause systemic symptoms and severe skin rash.

Psoriasis 

Psoriasis is a chronic skin disease and is also considered an autoimmune skin disease. That means your immune system is attacking your body instead of protecting it.

Common symptoms of psoriasis are:

• Red patches of skin (erythema)
• Itchy skin
• Joint swelling, stiffness, and pain

Plaque psoriasis is one of the most common types of psoriasis, while erythrodermic psoriasis is one of the most dangerous. Erythrodermic psoriasis often causes severely itchy and painful skin. 

The symptoms of erythrodermic psoriasis include: 

• Severe skin redness over a large part of the body (erythema)
• Skin shedding in large sheets rather than small flakes or scales
• Burnt-looking skin
• Pustules
• Severe pain and itching
• Increased heart rate
• Body temperature fluctuations 

Erythrodermic psoriasis may also cause swelling of the ankles, joint pain, fever, and/or chills. This is because it disrupts normal body temperature and fluid balance.

Because of the chronic and severe nature of this type of psoriasis, it is often treated with systemic treatments, including biologic drug therapies, such as Humira (adalimumab), Remicade (infliximab), Stelara (ustekinumab), and Taltz (ixekizumab).

Erythema Multiforme

Erythema multiforme can either be minor or major. Major EM is sometimes called Stevens-Johnson syndrome (SJS), a potentially life-threatening rash caused by medication. Unlike EM minor, SJS major causes extensive, blistering sores on the lips and in the mouth. They can also appear on the eyes and genitals.

Erythema Diagnosis 

Your healthcare professional will take your medical history and your report of symptoms. A physical examination will be done. Different types of erythema vary in how and where they appear, including their appearance on various skin tones.

Some types, like erythema multiforme, are easily identifiable just by how they appear on the skin. Other types of erythema will require additional testing, including bloodwork and biopsy. In a biopsy, some of the affected skin tissue is removed to be examined under a microscope.

Erythema causes that might include additional testing include:

• Psoriasis: Your doctor will ask about personal and family medical histories and your symptoms, and they will examine the skin, scalp, and nails. A skin biopsy may help confirm psoriasis and rule out other conditions. There is no specific blood test for psoriasis, but blood tests may be done to rule out other autoimmune diseases.
• Erythema chronicum migrans: If you have this rash and may have been bitten by a tick, a doctor will want to check for Lyme disease. Lyme disease is diagnosed using a blood test that detects antibodies to the bacteria that causes it.
• Keratolytic winter erythema: A diagnosis of KWE can be confirmed based on skin involvement. It is also supported by family history. Skin biopsies in people with KWE will often show signs of skin damage at the deepest levels of the skin. Genetic testing for KWE is rarely done due to the lack of availability or need.
• Palmar erythema: Palmar erythema is easily diagnosed based on sight alone. But your doctor will want to determine if it’s a symptom of an underlying condition. They will review your medical history and may order additional diagnostic tests.
• Fifth disease: Fifth disease can be diagnosed simply by looking at the rash. If a doctor is concerned about the serious consequences of the disease, they may request bloodwork to look for specific antibodies of the condition. 

Erythema Treatment

Most types of erythema are self-limiting and don’t require any treatment. They will clear up on their own over weeks or months. 

In cases where treatment is needed, your doctor will focus treatment on the type and underlying cause. If that cause is a bacterial infection, then it is treated with antibiotics. Erythema from a drug allergy starts with removing the drug that has caused the reaction and replacing it with another one if needed. 

Your doctor can also suggest and prescribe support care treatments and systemic therapies to manage different types of erythema and any additional symptoms. This might include: 

• Pain relievers and antihistamines to manage itching or skin pain
• Steroid creams or oral corticosteroids to manage skin inflammation
• IV medicines in severe cases, such as with erythrodermic psoriasis
• Cool compresses to help with skin pain and severe itch
• Soothing creams for itchy and sore skin
• Systemic medicines, if erythema is linked to a long-term condition like psoriasis
• Antiviral medicines related to viral infections

Summary

Erythema refers to redness of the skin. It occurs when the blood capillaries near the surface of the skin are congested, dilated, or inflamed. It can be seen as the result of many triggering events or underlying conditions, including infections and skin diseases such as psoriasis. Some conditions have erythema as part of their names.

A physical examination, medical history, and sometimes blood tests and a biopsy may be used to diagnose the cause. Treatment will depend on the cause. Sometimes erythema will clear up on its own, but other times it will need medication.

A Word From Verywell 

Erythema can affect anyone regardless of age, gender, skin type, or health status. It is always a good idea to be vigilant when it comes to your skin. You should inspect skin regularly and report any unusual changes to your healthcare professional.

If you are diagnosed with a type of erythema, you should take precautions to protect your skin. This includes protecting yourself from the sun and using sunscreen when outdoors. Avoid hot water and harsh skin products. Pat your skin dry after bathing, and use gentle moisturizers on the skin.