Erythema marginatum rheumaticum

A 13-year-old boy was referred to our clinic for urticaria. The skin eruption had developed the day before with a fever of 38.5° C, arthralgia and sore throat. The patient had been suffering from recurrent tonsillitis for 8 years. Over the last year, he had been taking 1 g/day josamycin for 15 days every month. On examination, the patient exhibited erythematous, annular, flat lesions, pale in color, some of them confluent producing [...]