Introduction

Rheumatic fever (RF) is a post-infectious inflammatory disease that occurs after a Group A streptococcal (GAS) pharyngitis, which affects multiple systems [1], [2]. It primarily affects children aged 5 to 15 years [2], [3].

Sydenham's chorea (SC), also known as Saint Vitus’ Dance, manifests as rapid, uncoordinated movements mainly impacting the face and hands due to the destruction of cells in the corpus striatum of the basal ganglia [6], [7]. The prevalence of chorea in patients with acute rheumatic fever (ARF) is 5-36% as reported by WHO and can occasionally be the sole manifestation of acute rheumatic fever (ARF) [6], [7]. It is included as a major ARF criterion per the Jones criteria, with a higher prevalence in females and children under 18 [7], [8].

In some cases of acute rheumatic fever (ARF), cardiac involvement may not be observed, this condition is known as subclinical carditis with a prevalence of 14-35% [8], [9]. Carditis is the only manifestation of acute rheumatic fever (ARF) that may result in permanent disability [10], [11]. Subclinical carditis can be identified in patients during their first ARF episode using ECHO, even if they present solely with isolated rheumatic chorea or migratory polyarthritis [10], [12]. Studies have shown that the mitral valve is the most common valve involved in RHD followed by the aortic valve [2], [8]. Most RHD patients with mitral valve involvement have shown improvement in valve symptoms with regular secondary prophylactic antibiotics over 5–10 years [10].

Treatments for Sydenham’s chorea (SC) include acute and long-term penicillin therapy, symptomatic medications like anticonvulsants (valproate, carbamazepine, phenobarbitone) and neuroleptics (pimozide, haloperidol, risperidone), and immunotherapy for resistant cases [12], [13]. Medications should be tapered once the patient's symptoms improve. Literature suggests that while most cases respond well to symptomatic treatment, immunotherapy is typically reserved for cases unresponsive to standard approaches [13].

We highlight a case where subtle valvular regurgitation was detected only by echocardiography, initially misinterpreted as a tic disorder.

The case was diagnosed as acquired subclinical RHD with chorea.

Intervention:

The patient was started on Tab. Penicillin V 250mg BD, Tab. Phenobarbitone 30mg TDS and Aspirin 75mg 8 tablets QID.

The Tab. Penicillin was given as a long-term prophylaxis for at least 10 years.

Follow-up:

At follow-up visits, the patient showed a reduction in involuntary movements, allowing for the gradual tapering of Tab. Phenobarbitone. Lifelong penicillin prophylaxis was advised to prevent recurrence and further complications.

Discussion

Rheumatic heart disease (RHD) is a complication of Acute rheumatic fever (ARF) and it remains a major health concern as it contributes to significant cardiovascular disease burden and mortality, especially in developing countries due to factors such as overcrowding, poor nutrition, and limited access to healthcare [2], [4]. India ranks among the top two countries that contribute to the highest estimated numbers of RHD-related deaths [1], [5].

This case underscores the necessity of recognizing Sydenham’s chorea (SC) as an indicator of acute rheumatic fever (ARF), especially in children who present with recent choreiform movements. Despite SC being a well-established major criterion for ARF within the Jones criteria, it can often be misdiagnosed as other movement disorders, such as tic disorders or dystonia, particularly when clinical signs are subtle. Subclinical RHD refers to the detection of structural or functional valvular damage via echocardiography, despite the absence of a heart murmur [2], [9]. Identifying subclinical RHD early allows for timely intervention and the commencement of secondary prophylaxis, crucial for preventing recurrent ARF episodes and limiting long-term cardiac damage.

Research indicates that consistent secondary prophylaxis with penicillin can greatly reduce the risk of disease progression and recurrence, contributing to better outcomes, particularly for patients with early-stage mitral valve involvement [10], [12].