The FP diagnosed scarlet fever based on the scarlatiniform rash, the fever, and the pharyngitis. Scarlet fever is an illness caused by toxin-producing group A β-hemolytic streptococci.
Most commonly, scarlet fever evolves from an exudative pharyngitis. Headache, sore throat, cervical lymphadenopathy, abdominal pain, nausea and vomiting, decreased oral intake, malaise, and fever may precede rash. Forchheimer spots (palatal and uvular petechiae and erythematous macules) may be present. The sandpaper rash, associated with blanching erythema and occasional pruritus, erupts 1 to 2 days after the fever starts.
Pastia’s lines are pink or red lines seen in the body folds (especially elbows and axillae) during scarlet fever. Linear hyperpigmentation may persist after the rash fades. Desquamation of the skin (especially of the hands and feet) ensues 3 to 4 days after the rash fades, and can persist for 2 to 4 weeks.
Scarlet fever usually follows a benign course; it is not the killer of children that it was in the pre-antibiotic era.
In this case, the FP explained the diagnosis to the mother and prescribed oral penicillin VK. The boy felt markedly better by the next day, and his mother continued to give him the penicillin for the full 10 days to prevent rheumatic fever.
Photos and text for Photo Rounds Friday courtesy of Richard P. Usatine, MD. This case was adapted from: Sanders MJ, French L. Scarlet fever and strawberry tongue. In: Usatine R, Smith M, Mayeaux EJ, et al, eds. Color Atlas of Family Medicine. 2nd ed. New York, NY: McGraw-Hill; 2013:208-212.
To learn more about the Color Atlas of Family Medicine, see: http://www.amazon.com/Color-Family-Medicine-Richard-Usatine/dp/0071769641/ref=dp_ob_title_bk
You can now get the second edition of the Color Atlas of Family Medicine as an app for mobile devices by clicking on this link: http://usatinemedia.com/