Chorea as the only presenting clinical feature of rheumatic fever: a case report

Sydenham's chorea (SC), a major neurological manifestation of acute rheumatic fever (ARF), is commonly seen in young children and adolescents. It is characterized by rapid, unpredictable, involuntary, and nonpatterned contractions affecting mostly distal limbs. It can also be associated with clinical or subclinical carditis. SC has been reported as a major manifestation in only 3.87% cases of acute rheumatic fever in Nepal.

The authors report a case of a 12-year-old boy with abnormal movement of his right hand and unsteady gait for 12 days. On examination, he had an abnormal hand grip with difficulty maintaining a tetanic contraction (Milkmaid's grip). Laboratory investigations revealed increased anti-Streptolysin O titre and erythrocyte sedimentation rate. Echocardiography revealed subclinical carditis. After thorough clinical examination and pertinent investigations, the final diagnosis of ARF with SC was made.

SC is a major clinical feature of rheumatic fever according to the revised Jones criteria. It is related to a previous Group A β-haemolytic Streptococcus pyogenes (GABHS) infection. Approximately 50-65% of the patients with rheumatic fever later develop clinically detectable carditis. Although a self-limiting condition, it might need treatment with antiepileptics, neuroleptics, and phenothiazines.

Any child presenting with a movement disorder should also be considered for SC, necessitating additional testing, including a cardiovascular assessment. It needs to be distinguished from other causes of movement disorders as well as psychiatric conditions. Treatment is necessary for moderate to severe chorea that interfere with daily activities. Compliance with subsequent antibiotic prophylaxis is essential for avoiding future cardiac complications.