A boy with erosive arthritis during treatment of severe group-A streptococcal infection

The patient was admitted to our department with major complaints of fever, swelling of the left thigh, and a cognition disorder. A blood culture yielded type T1, toxin-B-positive group-A streptococcus. Magnetic resonance imaging of the left foot showed fasciitis. Severe group-A streptococcal infection was diagnosed, and the administration of antibiotics, a massive dosage of gamma-globulin, and a steroid preparation were prescribed, which resulted in a general improvement in the symptoms and reductions in the swelling of the left foot and the second finger of the left hand without any sequelae. Following discharge from the hospital, however, destruction of the joint of the first toe of the right foot was recognized. A number of cases of post-streptococcal reactive arthritis (PSRA) have recently been reported, and the pathogenicity of this arthritis, which is different from that of rheumatic fever, has been noted. Severe group-A streptococcal infections, such as the one described here, may develop into erosive arthritis after the symptoms, that affect several organs, have disappeared. We believe that because it is possible for post-streptococcal reactive arthritis to develop, one should be aware of this when dealing with all clinical patients who have streptococcal infections.