Scarlet fever

Alternative names:

scarlatina

Definition:

A disease caused by an infection with group A B-hemolytic streptococcal bacteria that occurs in a small percentage of people with strep throat.

Causes, incidence, and risk factors:

Scarlet fever was once a common, serious childhood disease but now is easily treatable. The bacteria produces a toxin that causes a rash that initially appears on the neck and chest, then spreads over the body. Typically the rash begins as small red macules which gradually become elevated. The redness fades over a few days and the patient is left with a rough "sandpaper" feeling rash. While the rash is still red the patient may develop Pastia's lines, bright red coloration of the creases under the arm and in the groin. The rash may be denser in the groin, also. The rash usually lasts for 3 days. As the rash fades, peeling (desquamation) may occur around the finger tips, toes, and groin area. Risk factors are strep throat infection, although less than 50% of the patient's who develop scarlet fever have a history of a sore throat.