Chorea as the presenting feature of acute rheumatic fever in childhood; case reports from a low-prevalence European setting.

Background: Despite a notable decrease in acute rheumatic fever (ARF) incidence in the past few decades, there are still cases in our setting. Sydenham chorea (SC) may be the initial manifestation for this condition in childhood in a significant proportion of children. We report two cases of choreoathetosis in children as the first manifestation of ARF.
Case Presentation: A previously healthy 8-year-old boy presented with right hemichorea with a predominance in the brachial region, orofacial dyskinesias and speech difficulties for the past 2 weeks. The only medical history of interest was a common catarrhal illness 3 weeks before and nonspecific bilateral tenosynovitis in both feet since a year prior. A brain computerized tomography was normal and the echocardiogram showed mild mitral and aortic regurgitation, meeting ARF criteria. He demonstrated clinical improvement with treatment based on prednisone and carbamazepine. The second patient was a 10-year-old girl with choreic movements of the right half of the body and repetitive right eye closure of 1 week duration. She had symptoms of fever and rash the previous week and pharyngitis that resolved without antibiotic 2 months before. Blood tests revealed elevated C reactive protein (12 mg/dl) and erythrocyte sedimentation rate (96 mm/h). Brain magnetic resonance was normal and echocardiogram showed left ventricle dilation and mild mitral regurgitation, leading to the diagnosis of ARF. Due to neurological involvement, she received corticosteroids and intravenous immunoglobulin treatment, with worsening of neurological symptoms that required valproic acid with remission of the hemichorea. In addition skin lessions compatible with erythema marginatum appeared on the upper limbs.
Conclusions: SC should be the main diagnostic consideration in cases of hemichorea with normal neuroimaging in children. The cases reported highlight the need to maintain a high index of suspicion even in settings where incidende of ARF is low and the need to perform cardiological investigations in all patients with suspected SC, due to the possibility of subclinical valve lesions. Good adherence to secondary prophylaxis is crucial to avoid chorea relapses and worsening valve disease.