Erythema multiforme

  • Definition
    • Erythema multiforme is a skin disorder that comes from an allergic reaction or infection.

  • Alternative Names
    • Lyell's syndrome; Stevens-Johnson syndrome; Erythema multiforme minor; Erythema multiforme major

  • Causes
    • Erythema multiforme is a type of hypersensitivity reaction. It occurs in response to medicines, infections, or illness. Medicines that can cause this reaction include:

      • Barbiturates
      • Penicillins
      • Phenytoin
      • Sulfonamides

      Infections include:

      • Herpes simplex
      • Mycoplasma

      The exact cause is unknown. The disorder may start with damage to the blood vessels of the skin that damages skin tissues.

      Some forms of this condition are more severe than others.

      • Erythema multiforme minor is not very serious. Most erythema multiforme is caused by herpes simplex or mycoplasma infections.
      • Erythema multiforme major is more severe. It is also known as Stevens-Johnson syndrome. This form is usually caused by reactions to medicines, rather than infections. Acetaminophen and nonsteroidal anti-inflammatory drugs have caused very rare cases of Stevens-Johnson syndrome.

      Erythema multiforme occurs mostly in children and young adults.

  • Symptoms
    • Symptoms of erythema multiforme include:

      Skin sores may:

      • Start quickly
      • Come back
      • Spread
      • Be raised or discolored
      • Look like hives
      • Have a central sore surrounded by pale red rings, also called a target, iris, or bulls-eye
      • Have liquid-filled bumps or blisters of various sizes
      • Be located on the upper body, legs, arms, palms, hands, or feet
      • Include the face or lips
      • Appear evenly on both sides of the body (symmetrical)

      Other symptoms may include:

  • Exams and Tests
    • Your health care provider will look at your skin to diagnose this problem. The provider will ask if you have a history of risk factors or related diseases.

      Tests may include:

  • Treatment
    • Treatment goals include:

      • Controlling the illness that is causing the condition
      • Preventing infection
      • Treating the symptoms

      Your doctor may have you stop taking any medicines that may be causing the problem. Do not stop taking medicines without talking to your doctor first.

      Treatment of mild symptoms may include:

      • Medicines such as antihistamines to control itching
      • Moist compresses applied to the skin
      • Oral antiviral medicine if the reaction is caused by herpes simplex
      • Pain medication recommended by your doctor to reduce fever and discomfort
      • Topical anesthetics (especially for mouth sores) to ease discomfort that interferes with eating and drinking

      Treatment of severe symptoms may include:

      • Antibiotics for skin infections
      • Corticosteroids to control inflammation
      • Treatment in an intensive care or burn care unit for severe cases, Stevens-Johnson syndrome, and toxic epidermal necrolysis (top layer of skin separates from the lower layers)
      • Intravenous immunoglobulins (IVIG, an injection of healthy cells from donors into a vein) to stop the disease process

      Good hygiene and staying away from other people may help prevent secondary infections (infections that occur from treating the first infection).

      You may need skin grafting if large areas of your body are affected.

  • Outlook (Prognosis)
    • Mild forms of erythema multiforme usually get better in 2 to 6 weeks, but the problem may return. More severe forms may be hard to treat. Stevens-Johnson syndrome and toxic epidermal necrolysis have high death rates.

  • Possible Complications
    • Some complications of erythema multiforme are:

      • Body-wide infection (sepsis)
      • Loss of body fluids (shock)
      • Lesions on internal organs, causing inflammation of the heart (myocarditis), lung (pneumonitis), kidney (nephritis), and liver (hepatitis)
      • Permanent skin damage and scarring
      • Skin infection (cellulitis)
  • When to Contact a Medical Professional
    • Go to the emergency room or call the local emergency number (such as 911) if you have symptoms of erythema multiforme. Get emergency help immediately if a large area of your body is affected.

  • References
    • Currie GP, Plaza JA. Diseases of the skin. In: Bope ET, Kellerman RD, eds. Conn's Current Therapy 2014. 1st ed. Philadelphia, PA: Elsevier Saunders; 2013:section 4.

      Habif TP, ed. Clinical Dermatology. 5th ed. Philadelphia, PA: Elsevier Mosby; 2009:chap 18.

      Weber DJ, Cohen MS, Morrell DS, Rutala WA. The acutely ill patient with fever and rash. In: Mandell GL, Bennett JE, Dolin R, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Disease. Philadelphia, PA: Elsevier Churchill Livingstone; 2009:chap 52.