Erythema multiforme Health Article

Definition

Erythema multiforme is a skin disorder due to an allergic reaction or infection.

Alternative Names

Lyell's syndrome; Stevens-Johnson syndrome; Toxic epidermal necrolysis

Causes, incidence, and risk factors

Erythema multiforme is a type of allergic reaction that occurs in response to medications, infections, or illness. Medications include:

• Barbiturates
• Penicillins
• Phenytoin
• Sulfonamides

Infections include:

• Herpes simplex
• Mycoplasma

Most erythema multiforme is associated with herpes simplex or mycoplasma infections.

The exact cause is unknown. The disorder is believed to involve damage to the blood vessels of the skin, followed by damage to skin tissues.

Some forms of this condition are more severe than others. Erythema multiforme minor is not very serious. Erythema multiforme major (also called Stevens-Johnson syndrome) is more severe. The more severe form is usually caused by reactions to medications, rather than infections.

Erythema multiforme occurs primarily in children and young adults.

Symptoms

• Fever
• General ill feeling
• Itching of the skin
• Joint aches
• Multiple skin lesions:
  • Start quickly and may return
  • May spread
  • May appear as a nodule, papule, or macule
  • Central lesion surrounded by pale red rings, also called a "target", "iris", or "bulls-eye"
  • May have vesicles and blisters of various sizes (bullae)
  • Located on the upper body, legs, arms, palms, hands, or feet
  • May involve the face or lips
  • Usually symmetrical

Other symptoms that may occur with this disease:

• Bloodshot eyes
• Dry eyes
• Eye burning, itching, and discharge
• Eye pain
• Mouth sores
• Vision abnormalities

Signs and tests

The diagnosis is based mainly on the appearance of the skin lesion, especially if there is a history of risk factors or related diseases.

Tests may include:

• Nikolsky's sign
• Skin lesion biopsy and microscopic examination of the tissue