Erythema: Types, Causes, Symptoms, Diagnosis, Prevention and Treatment
Erythema is a common dermatological condition seen across all age groups. It refers to redness of the skin caused by increased blood flow in the superficial blood vessels. In most cases, erythema is temporary and harmless, but sometimes it can signal underlying infections, allergic reactions, autoimmune disorders, or life-threatening illnesses.
Skin redness can appear in patches, rings, nodules, or rashes, depending on its cause and type. Identifying the correct type of erythema is essential for optimal treatment.
What is Erythema?
Erythema is medically defined as:
Redness of the skin resulting from vascular dilation (hyperemia) of blood capillaries.
When the skin is irritated, inflamed, or injured, the body sends more blood to the area, leading to noticeable redness.
Physiological vs Pathological Erythema
Type Meaning Example
Physiological Normal response to body changes Blushing, exercise
Pathological Caused by diseases or infections Erythema nodosum, erythema migrans
Epidemiology
• Common in dermatology and allergy clinics
• Can affect any age, including infants
• Some types more common in:
• Females (Erythema nodosum, Erythema multiforme)
• People with autoimmune or infectious diseases
All Types of Erythema
Erythema has several types classified based on appearance, cause, and body involvement. Major types include:
1. Erythema Nodosum
Painful, red nodules mostly on shins.
• Causes: Tuberculosis, Streptococcal infection, Pregnancy, Sarcoidosis, Inflammatory bowel disease
• Symptoms: Tender nodules, fever, joint pain
• Treatment: Anti-inflammatory medicines, treat underlying cause
2. Erythema Multiforme
Immune-mediated condition presenting as “target lesions” with concentric rings.
• Causes: Herpes simplex virus (most common), medications (sulfa drugs, antibiotics)
• Symptoms: Target rash on hands, feet, mucosal ulcers
• Severe Form: Stevens-Johnson Syndrome (SJS)
• Treatment: Antivirals, corticosteroids, stop the triggering drug
3. Erythema Migrans
A hallmark sign of Lyme disease caused by tick bites.
• Appearance: Bull’s-eye or circular expanding rash
• Symptoms: Fever, fatigue, joint pain weeks later
• Treatment: Antibiotics (Doxycycline)
4. Erythema Toxicum Neonatorum
A benign rash in newborns, seen within first 1–3 days of life.
• Appearance: Small red papules, pustules on face/trunk
• Treatment: No treatment needed; resolves within a week
5. Erythema Chronicum Migrans
Chronic stage of Lyme disease erythema, untreated initial rash expands and persists.
6. Erythema Induratum
Chronic recurrent nodules linked with Tuberculosis.
• Appearance: Ulcerating nodules on legs
• Treatment: Anti-TB therapy
7. Erythema Ab Igne
Also known as toasted skin syndrome.
• Cause: Repeated exposure to heat (heaters, laptops)
• Symptoms: Reticulated brown-red patches
• Risk: May progress to skin cancer
• Treatment: Avoid heat, topical creams
8. Erythema Infectiosum (Fifth Disease)
Viral childhood disease caused by Parvovirus B19.
• Appearance: “Slapped cheek” rash
• Symptoms: Fever, runny nose then rash
• Treatment: Self-limiting, symptomatic care
9. Erythema Annulare Centrifugum
Ring-shaped expanding rash due to allergies, infections, or autoimmune triggers.
10. Erythema Dyschromicum Perstans
Blue-gray skin hyperpigmentation particularly in darker skin tones.
Other Less Common Types
Type Feature Common Cause
Erythema Elevatum Diutinum Red-purple nodules on joints Vasculitis
Erythema Marginatum Rash with rheumatic fever Autoimmune
Palmar Erythema Red palms Liver disease, pregnancy
Erythema Gyratum Repens Wood-grain appearance Cancer marker
Photo-induced Erythema Sunburn UV exposure
Causes of Erythema
Erythema can appear due to multiple body responses. Main causes include:
1. Infectious Causes
• Bacterial → Streptococcus, Mycobacterium tuberculosis
• Viral → HSV, Parvovirus B19
• Tick-borne → Lyme disease
2. Immune & Allergic Causes
• Autoimmune disorders
• Hypersensitivity reactions
• Food, drugs, latex allergy
3. Physical Factors
• Heat, radiation, UV light (sunburn)
• Pressure or friction on skin
4. Systemic/Metabolic Conditions
• Pregnancy (palmar erythema)
• Liver cirrhosis
•™Inflammatory bowel diseases
5. Medication-Induced
• NSAIDs, antibiotics, anti-seizure drugs, sulfonamides
• Signs and Symptoms
Symptoms vary with type but common features include:
• Redness of skin (localized or widespread)
• Warmth and swelling
• Pain or tenderness (especially nodosum)
• Itching or burning sensation
• Rash in rings, nodules, or target shapes
• Fever, fatigue (in infection-related erythema)
• Joint pain (IBD, sarcoidosis related)
When it is Severe
• Blisters, skin peeling
• Breathing difficulty
• Rapid rash spread
• Mucosal involvement
This may indicate Stevens-Johnson Syndrome → Medical Emergency
Diagnosis of Erythema
Diagnosis requires a detailed clinical evaluation including:
1. Medical History
Exposure to infections, ticks, new drugs, heat
2. Physical Examination
Rash pattern, tenderness, site involvement
3. Laboratory Investigations
Depending on suspected cause:
• CBC, ESR, CRP → inflammation
• Throat swab → streptococcus
• Tuberculosis tests
• Liver function tests (for palmar erythema)
• Parvovirus test (children)
4. Skin Tests
• Skin biopsy for unknown cause
• Patch testing for allergies
5. Imaging
• Chest X-ray (sarcoidosis, TB suspected)
Prevention of Erythema
Although not all types are preventable, general strategies include:
• Avoid strong sun exposure → sunscreen, protective clothing
• Prevent tick bites → insect repellents
Avoid unnecessary antibiotics or trigger medications
• Maintain skin hygiene
• Keep heat sources away from skin
• Early treatment of infections
• Manage autoimmune disorders timely
Special Advice:
• Pregnant women with palmar erythema → regular liver checks
• Children → hygiene & vaccination for viral illnesses
Treatment of Erythema
Treatment depends on underlying etiology.
General Treatment Measures
• Cold compresses
• Moisturizers to reduce irritation
• Avoid scratching
• Hydration and rest
Medications
Drug Type Used For
Antihistamines Allergic erythema, itching
NSAIDs Pain & swelling in nodosum
Corticosteroids (topical or oral) Severe inflammation, autoimmune causes
Antibiotics Bacterial causes (e.g., Lyme disease)
Antivirals HSV-related erythema multiforme
Immunosuppressants Persistent autoimmune cases
Lifestyle Modifications
• Avoid heat exposure (Ab Igne)
• Skin-friendly diet rich in antioxidants
• Stress reduction → reduces immune flare-ups
Treatment of Specific Types
Type Treatment Focus
Nodosum Treat infection/IBD + NSAIDs
Multiforme Antivirals + stop drug triggers
Infectiosum Fever control, rest
Migrans Doxycycline
Induratum Anti-TB therapy
Toxicum Neonatorum Supportive care only
If erythema worsens with blisters or mucosal damage → Hospitalization required.
Complications
Untreated or severe erythema can lead to:
• Pigmentation changes
• Ulcers or scarring
• Chronic pain
• Vision impairment (severe SJS)
• Sepsis in infection-related cases
Early diagnosis prevents complications.
Prognosis
• Most types recover completely with proper care
• Chronic or recurrent in autoimmune or TB-related erythema
• Severe allergic reactions require lifelong trigger avoidance
Frequently Asked Questions (FAQs)
1. Is erythema contagious?
No. But if caused by infections like parvovirus or Lyme disease, those infections may be contagious.
2. Can erythema go away on its own?
Yes, mild types (sunburn, erythema toxicum neonatorum, infectiousum) resolve spontaneously.
3. When should I visit a doctor?
•If erythema is:
• Very painful
• Spreading fast
• Accompanied by fever, breathing difficulty, blisters You should seek medical help urgently.
4. What is the difference between erythema and rash?
A rash is any change in skin appearance; erythema specifically refers to redness from increased blood flow.
5. Can stress cause erythema?
Yes, emotional stress can trigger physiological erythema such as blushing or worsening autoimmune flares.
6. Which vitamin is important for skin healing?
Vitamin C, Vitamin E, Vitamin A, and Zinc help skin repair and immunity.
7. How long does erythema last?
From a few days (infectiousum) to months (nodosum), depending on the type and cause.
Conclusion
Erythema is a clinical sign rather than a disease itself. It can appear from:
• Infection
• Allergy
• Autoimmune condition
• Heat exposure
• Drug reaction
Recognizing the type, identifying the underlying cause, and receiving timely treatment prevents complications and ensures a better outcome.
If a skin rash or redness persists or worsens, consulting a dermatologist is always recommended.
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Writer: Vandita Singh, Lucknow (GS India Nursing Group)