Sydenham’s chorea in Sudan

Background: Sydenham’s chorea (SC), is the most common form of acquired chorea in childhood, it is considered as neurological complication of streptococcal pharyngitis. Our aim was to determine the clinical pattern, association of Sydenham’s chorea with other manifestation of ARF and the laboratory ndings of Sydenham’s chorea among Sudanese patients. Methods: This study is descriptive , retrospective cross- sectional study. Fifty patients with different age groups, were diagnosed as having Sydenham’s chorea & followed up at The National center for Neurological sciences, in the period (Jan2017 to Nov2019). Data were obtained after patients consent of by personal interview or personal review of patients records through a designed questionnaire including demographic data, symptoms, co morbid illness, risk factors, physical examination and related investigations. Results: The patients’ median age was 13.7 years: 88% of the cases occurred between 7-17 years with female predominance(35) . Generalized chorea was seen in 33 (66%) and hemichorea 17 (34%) patients. weakness and hypotonia were common, behavior change (44%), dysarthria (71%), gait change(17.20%)and deterioration of handwriting (13%) Arthritis occurred in (36%), carditis 30 (60%), arthritis and carditis in 18(36%), and pure chorea 14 (28%). Erythema marginatum and subcutaneous nodules were not observed in our patients. Only13 patients (26%) gave a history of pharyngitis. Conclusion : There were clear evidence of familial predisposition. Sydenham’ chorea commonly presents acutely in majority of patients. Chorea rstly appeared with oro-fascial movement followed by limb involvement. Minority of patients gave a history of pharyngitis. Brain imaging was normal. This is descriptive and retrospective cross-sectional study in Sudanese patients with Sydenham’s chorea.

Conclusion : There were clear evidence of familial predisposition. Sydenham' chorea commonly presents acutely in majority of patients. Chorea rstly appeared with oro-fascial movement followed by limb involvement. Minority of patients gave a history of pharyngitis. Brain imaging was normal. Background Sydenham's chorea also known as St. Vitus dance, St. Johannis' chorea, chorea minor, and rheumatic chorea, is one of the major clinical manifestations of acute rheumatic fever (ARF) and it is the most common form of acquired chorea in childhood. It is considered as neurological complication following infection with particular strains of streptococci (i.e., group A beta-hemolytic streptococci [2] . The initial illness is usually characterized by a sore throat (pharyngitis) that may be followed, with in approximately 1 to 5 weeks, by the sudden onset of acute rheumatic fever [4] . The symptom-free period between recovery from pharyngitis to the onset of acute rheumatic fever is known as the "latent period".
In about 20% of patients Sydenham's chorea occurs as the only manifestation of ARF. It is also considered a delayed complication of acute rheumatic fever, occurring as late as 12 months after the initial throat infection. Acute rheumatic fever is an in ammatory disease (i.e., sequelae) following group A streptococcal infection that may affect multiple tissues and organs, including the joints, skin, connective tissues directly beneath the skin (subcutaneous tissues), heart, and brain [1,2;4] .
Sydenham's chorea may occur, with other symptoms of acute rheumatic fever or as an isolated form. In the isolated form, laboratory evidence of a preceding streptococcal infection may be lacking [4] .
Although more common in children, rheumatic fever can also occur in adults, and migratory arthritis is a common presenting symptom.
These patients need to be considered candidates for prophylactic therapy, as evidenced by an outbreak in 10 young adults in the San Diego Naval Training Camp, three of whom developed valvular damage [5] .
It is a movement disorder characterized by chorea, emotional lability, and hypotonia. Emotional changes manifest themselves in outbursts of inappropriate behavior, including crying and restlessness. In rare cases, the psychologic manifestations may be severe and may result in transient psychosis [6] .

Study design:
This study is descriptive and retrospective cross-sectional study. Data were obtained after patients consent of by personal interview or personal review of patients records.

Study tools:
A retrospective collection of data from the patients with Sydenham's chorea or their records through a designed questionnaire including demographic data, symptoms, co morbid illness, risk factors, physical examination & related investigations.
Echocardiography and electrocardiography were performed in all patients, brain image was done in 11 patients.

Analysis:
All collected data were entered into the computer using the statistical package program for social science (SPSS) to analyze the data via simple descriptive statistics. (Analyzer is specialized personnel in SPSS).

Results
This study is descriptive and retrospective cross-sectional study in Sudanese patients with Sydenham's chorea.
Sydenham's chorea can present at different age group, the majority of the cases occurred between 7 -17 years. The patients' median age was 13.7 years.
In this study, 50 patients were diagnosed to have Sydenham's chorea, among them 35 patients (70%) were females and 15 patients (30%) were males. There was positive family history of acute rheumatic fever in 34% of the studied group. The chorea lasted from 2 to 4 weeks in 26 patients (52%), 5 to 10 weeks in19 patients (38%) and 11 to 15 weeks in 5 patients (10%).
In all patients the movements were suppressed during sleep (100%) and this was being the provocation factor 12 patients (25%).
The association of Sydenham's chorea and other manifestations of acute rheumatic fever : The association of Sydenham's chorea and other manifestations of acute rheumatic fever, carditis occurred in 30 patients (60%), 18 patients had arthritis only (36%), arthritis and carditis in 18 patients (36%), and pure chorea 14 (28%). Erythema marginatum and subcutaneous nodules were not observed in our patients.
Ten of 50 patients (20%) had a recurrent attack; all of them were the second attack. The interval between attacks varied from 2-3 years. Carditis was detected in all patients with recurrences Discussion This study revealed that 35 (70%) of the patients were female and 15(40 %) patients were male.
Females were found to be most frequently affected than males The mean age incidence of patients of Sydenham ' s chorea was found to be 13.7 , the median age range between 7 to 27 years .
In Australia study the female percentage was (89.8 %) & the mean age was 10.9 years at rst episode [7] . In the Indian study girls incidence was (60 %); the mean age at presentation was 11.1 yr (range 7-16 yr) [8] .
The Turkey study revealed that, the mean age at the onset of the symptoms was 11.7 +/-2.6 years (range 6-17 years). The study revealed that 63% of the patients were female and 37% were male (male/female: 1.7/1) [9] .
In comparison to this study con rmed that the percentage of our female affection predominated the male affection.
The mean age in our study is higher than that found in other studies; this may re ects that, Sydenham's chorea occurs at higher age group in Sudanese in comparison to other population or it can be attributed to second attack of Sydenham's chorea considering that sydenhams chorea occasionally presents a subtle form .
Much of the studies documented that Sydenham's chorea is still a common problem in the developing countries due to the high incidence of ARF; the Assiut, Egypt study found that rheumatic chorea was most common among the studied population [10] .
The chorea last from 2 to 15weeks in the study ,this nding is in line with the observations of others [7] .Regarding the pattern of onset of chorea most patients were found to have acute onset (67.3o%) rather than gradual (32,70%) ,this is supported by the fact that Sydenham's chorea typically has usually acute onset .
Generalized chorea in patients with Sydenham's chorea was seen in 33 (66%), hemichorea in 17 patients (34%), comparing this with India study, generalized chorea was seen in 40 (66.6%) and hemichorea in 20 patients (33.3). This re ects that Sydenham ' s chorea commonly present as generalized rather than partial chorea.
The study revealed that most movements initialy started at the limbs (82%%) rather than orofascial (18%) . This is described well in the literature.
Higher function disturbances were common; of which speech was the most affected item, mainly as dysartheria (71.1%); this nding correlates with the review, that chorea commonly associated with dysartheria.
Darting tongue & milking sign were found in 42.3% of all patients.
Psychiatric symptoms were reported in 23 patients (44.2%) mainly as restlessness & emotional labiality. This con rmed well with the literature [5] which reported high frequency of these symptoms in Sydenham's chorea.
In our study, past history of ARF occurred in 12 (24%) patients, in comparison to the Turkey study a past history of ARF [9] was accounted for 30%. Family history of ARF occurred in 34%in this study; this is similar to the results of other studies, such as Sydenham's chorea study in western Pennsylvania in which family history of ARF existed in 30% of patients [11] .
The study found ten patients (20%) had a recurrent attack; the recurrence rate was 37.9% in the Turkey study; this can be explained by the short time of our study & the lack of close follow up to study sample for long period.
The duration of Sydenham's chorea varied between 7 to 50 days in our study; closely related to other reports. All the patients with Sydenham's chorea had their movement stopped completely within 1 to 2 weeks after treatment, no single case persisted, this is goes with the literature as persistence rate in patients with is low in Sydenham's chorea [3,5] .
The study showed carditis occur in 30 patients (60%). six patients (12%) with pure chorea had silent valvitis demonstrated only by echocardiographic testing but without any signi cant murmur (mitral regurgitation in 1 and combination of mitral and aortic regurgitation in 3 cases). So carditis increased up to 72%, re ects high affection (more severe disease) in Sudanese patient.
In our study Only 13 patients (26%) gave a history of pharyngitis ,this is because pharyngitis may precede the onset of chorea by as much as 6 months, many patients may not provide a history of streptococcal infection, but still we have allow percentage as history of pharyngitis is obtained in 41%, in Turkey study.
Elevated ASO levels were detected in 44 (88%) of the patients. Highly elevated ESR was detected (>100 mm/h) in 18 (14%) and moderately elevated ESR (30-70 mm/h) in 77 (59%) patients. This re ected that acute phase reactants were raised almost in most of the patients with Sydenham's chorea. In comparison to other studies in Turkey Elevated ASO titre in 83%; in Indian study; a raised ESR and positive ASO titer were seen in 37 and 20 patients respectively.
Prolonged PR or rst-degree block was noted in 9 (18%) patients in our study & was found to be prolonged in 13% of patients in India one.
Mitral regurgitation was found in 20 patients (83%), aortic regurgitation in 6 patients (44%) and combination of mitral and aortic regurgitation in 10 patients (27%). The mitral valve was the most commonly affected valve (64%), followed by aortic valve (22%). The mitral valve is the most commonly affected valve in rheumatic heart disease.
In 50 patients with Sydenham's chorea, brain image(brain MRI) was done in 11 patients, all was reported to be normal, this goes with most of the studies done for that issue, one of these was done in western Pennsylvania which revealed that in patients with Sydenham ' s chorea, brain computed tomography was abnormal in just 1 of 20 patients and that the abnormalities did not aid in diagnosis and included nonspeci c increased nding [11] .

Conclusion
The mean age of presentation of Sydenham's chorea was between 7-17 years. The study showed predominant female preponderance. The study showed clear evidence of familial predisposition.
Sydenham ' s chorea commonly presents acutely in majority of patients Invariably in all cases the movements were suppressed during sleep, stress being the most provocational factor.
Chorea rstly appeared with orofascial movement followed by limb involvement. Darting tongue & milking sign were common. Generalized chorea was more prevalent than hemichorea Psychiatric symptoms manifested as emotional liability restlessness and depression. Eighteen patients had arthritis only (36%), carditis 30 (60%), arthritis and carditis in 18(36%), a pure chorea 14 (28%). Erythema marginatum and subcutaneous nodules were not observed in our patients. Elevated ASO levels and ESR were detected in most of the patients, minority of patients gave a history of pharyngitis. Prolonged PR or rst-degree block was noted.
The mitral valve was the most commonly affected valve followed by aortic valve. Brain imaging, which was performed in a minority of cases, was evaluated as normal.

Recommendations
As Sydenham's chorea is a common disease in sudan ,further studies are need to be conducted in this direction .All Patients with chorea should be screened for Sydenham's chorea Long term adherence to secondary prophylaxis is crucial following all episodes of acute rheumatic fever, including chorea, to prevent recurrence.

Declarations
Availability of data and materials The materials datasets used and/or analyzed during this study are available from the corresponding author on reasonable request.

Ethical Considerations
Ethical approval was obtained from State Ministry of Health, ethical committee.