Sydenham's Chorea.

BACKGROUND: Sydenham's chorea is the most common acquired movement disorder of adolescence. This clinical manifestation of acute rheumatic fever has a clear and documented relationship with Group A streptococcal infections. The symptoms are involuntary choreiform movements that can affect the face and all extremities. The pathophysiology remains unclear.

CASE REPORT: A 12-year-old female was brought to the emergency department with a 2-week history of involuntary muscle spasms of her right arm and leg. Her parents reported intermittent slurred speech and difficulty grasping utensils. Physical examination revealed an awake, alert, age-appropriate female with normal cranial nerves. Patient was found to have choreoathetoid movements on the right extremities with dystonia of right leg with ambulation. Neurology consultation, computed tomography of the head, and magnetic resonance imaging of the brain did not show any acute pathology. Echocardiogram did show mild tricuspid regurgitation, suggestive of rheumatic fever. Anti-streptolysin O titer was markedly elevated, along with DNAse-B antibodies. The patient had marked improvement of movement disorder at just over 1 week later. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Sydenham's chorea is a rare but important movement disorder often related to Group A streptococcus and rheumatic fever. The incidence of rheumatic fever has been decreasing in North America but continues to be much more prevalent in developing countries as well as immigrant populations. This diagnosis is rare and can occasionally be misdiagnosed as a "fidgety" child or as a psychiatric manifestation. Sydenham's chorea is important to diagnose because acute treatment and prophylactic antibiotics can help improve symptoms and minimize cardiac damage.