Photoclinic: Atypical Rash Associated With Streptococcal Pharyngitis

A 16-year-old girl presented with a painful rash on her hands and feet, and a sore throat. The rash, which "itched and burned," had appeared on her palms and soles a day earlier and had worsened overnight.

The patient reported that the sore throat started about 2 weeks earlier. It was accompanied by fatigue and fever, although she was not febrile at the time of presentation. She was not taking any medication other than an antihistamine intermittently for the itching.

Rachel St John, MD, of Washington, DC, noted small, well-circumscribed, intensely erythematous lesions on the patient's feet and hands, concentrated on the palms and soles (A). Throat examination revealed an extremely erythematous posterior pharynx, tonsillar exudates, and significant bilateral anterior cervical adenopathy. Results of a rapid streptococcal antigen test were positive.

Because the girl had had a sore throat and fever for 2 weeks and the lesions resembled those of Janeway lesions, an infectious disease specialist was consulted and a blood culture was obtained. The patient was treated with a 0.9-million unit dose of benzathine penicillin intramuscularly. Based on her clinical stability and the lack of major Jones criteria, a 10-day course of oral penicillin therapy, 500 mg tid, was prescribed thereafter.

At follow-up 3 days later, the rash, sore throat, and fatigue had almost completely resolved. Cardiac findings continued to be normal, and the blood culture grew no organisms. At 1-week follow-up, the rash and symptoms had completely resolved, leaving desquamation of the palms and soles. No pathogens grew in the blood culture.

Concurrently, a 22-year-old woman who worked in the pediatric department where the patient was treated had experienced similar symptoms and sought treatment at a medical facility near her home. Streptococcal pharyngitis was diagnosed via rapid antigen testing. She responded quickly to antibiotic therapy. Her rash had involved the buttocks and knees (B and C), as well as the palms and soles. She also experienced skin desquamation in the convalescent period. Her blood culture also remained without growth. She had not been taking medications during the development of her rash.

The rash may have been an exanthema related to a common viral illness. However, the resolution of symptoms with penicillin therapy suggests that this rash was most likely a toxin-mediated immune response. It is possible this is a new presentation of group A streptococcal infection that differs from the classic scarlatiniform rash often seen with concurrent group A streptococcal pharyngitis.