Scarlet fever begins with invasion of streptococci through either the pharynx or a skin wound. Erythematous macules and papules, that begin on the neck and spread downward over the trunk to the extremities, appear 24 to 48 hours after the initial infection. In severe cases the exanthem may be petechial. "Pastia's lines" occur, which is the presentation of petechiae in a linear pattern along the major skin folds such as along the axillae and antecubital fossa. A facial flush with circumoral pallor is common, and the palms and soles are typically spared. Streptococcal scarlet fever produces a bright red erythema of the tongue known as strawberry tongue. This sign is not seen in staphylococcal scarlet fever. Later, desquamation occurs in the same direction as the initial spread of the eruption. Generalized lymphadenopathy is common.

Differential diagnosis

Drug eruptions, Kawasaki disease, toxic shock syndrome, measles and rubella are part of the differential for scarlitiniform eruption.

Treatment

Penicillin is the treatment of choice for scarlet fever.