Erysipelas

Definition

Erysipelas is a skin infection which often follows strep throat.

Description

Erysipelas, also called St. Anthony's fire, is caused by infection by Group A Streptococci. This same type of bacteria is responsible for such infections as strep throat, and infections of both surgical and other kinds of wounds in the skin. The infection occurs most often in young infants and the elderly.

Causes & symptoms

Erysipelas usually occurs rather abruptly. When the preceding infection was strep throat, the rash begins on the face. Occasionally, when the preceding infection was of a wound from an injury or operation, the rash will appear on an arm or leg.

Classically, the usual presentation is a bright-red, butterfly-shaped rash appearing across the bridge of the nose and the cheeks. It is hot to the touch, painful, shiny, and swollen, with clearly defined margins. The edges of the rash are a raised ridge, hard to the touch. There may be fluid-filled bumps scattered along the area. The rash spreads rapidly. Some patients have swelling of the eyelids, sometimes so severe that their eyes swell shut. The patient may have fever, chills, loss of energy, nausea and vomiting, and swollen, tender lymph nodes. In severe cases, walled-off areas of pus (abscesses) may develop beneath the skin. If left untreated, the streptococcal bacteria may begin circulating in the bloodstream (a condition called bacteremia). A patient may then develop an overwhelming, systemic infection called sepsis, with a high risk of death.

Diagnosis

The rash of erysipelas is very characteristic, raising the practitioner's suspicion towards that diagnosis, especially when coupled with a history of recent strep infection. Attempts to culture (grow) the bacteria from a sample of the rash usually fail. When the bacteria are present in the blood, they may be grown in a laboratory, and identified under a microscope. Other laboratory tests involve reacting fluorescently-tagged antibodies with a sample of the patient's infected tissue. This type of test may be successful in positively identifying the streptococcal bacteria.

Treatment

Penicillin is the drug of choice for treating erysipelas. It can usually be given by mouth, although in severe cases (or in cases of diagnosed bacteremia) it may be given through a needle placed in a vein (intravenously).

Even with antibiotic treatment, swelling may continue to spread. Other symptoms, such as fever, pain, and redness, usually decrease rapidly after penicillin is started. Cold packs and pain relievers may help decrease discomfort. Within about 5-10 days, the affected skin may begin drying up and flaking off.

Prognosis

With prompt treatment, the prognosis from erysipelas is excellent. Delay of treatment, however, increases the chance for bacteremia and the potential for death from overwhelming sepsis. This is particularly true of people with weakened immune systems (babies, the elderly, and people ill with other diseases, especially Acquired Immunodeficiency Syndrome, or AIDS). Frequently, an individual who has had erysipelas will have it occur again in the same location.

Prevention

Prevention involves appropriate and complete treatment of streptococcal infections, including strep throat and wound infections.

Key Terms

Bacteremia

The presence of bacteria in the blood.

A bacteria that causes erysipelas and strep throat, as well as other infections.

Further Reading

For Your Information

Books

• Bolognia, Jean L., and Irwin M. Braverman. "Skin Manifestations of Internal Disease." In Harrison's Principles of Internal Medicine, edited by Anthony S. Fauci, et al. New York: McGraw-Hill, 1998.
• Sherris, John C., and Kenneth Ryan. "Streptococci." In Sherris Medical Microbiology: An Introduction to Infectious Diseases, edited by Kenneth J. Ryan. Norwalk, CT: Appleton and Lange, 1994.
• Stevens, Dennis L. "Infections of the Skin, Muscle, and Soft Tissues." In Harrison's Principles of Internal Medicine, edited by Anthony S. Fauci, et al. New York: McGraw-Hill, 1998.
• Stoffman, Phyllis. The Family Guide to Preventing and Treating 100 Infectious Diseases. New York: John Wiley and Sons, Inc., 1995.
• Todd, James. "Bacterial Infections." In Nelson Textbook of Pediatrics, edited by Richard Behrman. Philadelphia: W.B. Saunders Co., 1996.

  Periodicals

• Huerter, Christopher, et al. "Helpful Clues to Common Rashes." Patient Care 31, 8 (April 30, 1997): 9+.

Gale Encyclopedia of Medicine. Gale Research, 1999.