Chorea minor, also known as Sydenham’s chorea, is a neurologic autoimmune disorder that usually occurs a few weeks after an infection with group A ß-hemolytic streptococci. The disease is usually a late manifestation of rheumatic fever.
What is chorea minor?
Chorea always results from impairment of the basal ganglia. Typical of chorea are involuntary and sudden movements of the legs, arms, face, trunk, and neck. The movements occur at rest and during the performance of voluntary movements. The term chorea comes from the Greek “choreia.” The term was used to describe the dances of the insane. Chorea minor was also called St. Vitus’ dance in the Middle Ages. Chorea minor is one of the most common forms of chorea. Since chorea minor is a possible manifestation form of rheumatic fever, it also bears the names chorea rheumatica or chorea infectiosa. The disease mainly affects six- to thirteen-year-old girls. In rare cases, adults up to 40 years of age also become ill.
Causes
Minor chorea is an autoimmune disorder that occurs several days to weeks after a streptococcal infection. Typical strep infections are found in the throat and pharynx. During this infection, the body produces antibodies against the pathogens. However, these mistakenly react not only to the streptococci, but also to the body’s own tissues. The surface structure of some body tissues resembles the structure of streptococci. Thus, the antibodies attack the body’s own cell structures. As a result, the so-called rheumatic fever develops. In addition to the cells of the heart, the basal ganglia in the brain are also attacked. 10 to 15 percent of all patients with rheumatic fever develop minor chorea. The basal ganglia are located below the cerebral cortex. The nuclei or nucleus areas play an important role in motor, cognitive and limbic regulation. They are an essential component of the extrapyramidal motor system (EPMS). Unlike Huntington’s disease, in minor chorea the basal ganglia are not irreversibly destroyed, but only temporarily affected. Due to the inflammatory reactions, the movement-inhibiting basal ganglia are limited in their function. The movement-promoting basal ganglia in the substantia nigra and pallidum are partially disinhibited. This results in the characteristic overshooting movements. Symptoms are more pronounced the more cells in the basal ganglia have been damaged and the greater the inflammation in the brain.
Symptoms, complaints, and signs
The movement disorders that occur in chorea minor belong to the group of extrapyramidal hyperkinesias. They are similar to the symptoms of chorea major. So-called hyperkinesias occur. Hyperkinesias are short-lasting, uncoordinated and uncontrollable muscle twitches of the arms, legs, feet and hands. At first, these movements often go unnoticed. At school, the affected children stand out due to poorer handwriting. They appear clumsier, drop objects more frequently or can no longer eat properly with a knife and fork. Hyperkinesia also occurs in the facial muscles. The children make faces without realizing it. The hyperkinesias of the pharyngeal muscles lead to difficulties in speaking and swallowing. The uncoordinated muscle twitches cause affected individuals to speak in a choppy manner (dysarthria). They frequently swallow (dysphagia) and run the risk of suffering from what is known as aspiration pneumonia. In aspiration pneumonia, inflammation develops due to various substances that enter the lungs with the saliva. Characteristic of chorea minor is also the flycatcher or chameleon tongue. Twitches in the tongue muscles cause involuntary extension and sudden retraction of the tongue. The hyperkinesias increase during emotional stress and stressful situations. Because affected children are often ashamed of these symptoms, they try to suppress the movements as much as possible. In addition to hyperkinesias, however, muscle hypotonia can also develop. The children no longer have strength in their muscles and react with weakened muscle reflexes. Mental disorders such as attention deficit disorder, fatigue, apathy, irritability, restlessness and, in rare cases, psychosis can also occur in the context of chorea minor.
Diagnosis and course
The first clues to chorea minor are provided by the clinical picture with the chorea-typical movement disorders. The medical history also shows typical clues. In most cases, the patient is a child of school age who has previously experienced angina tonsillaris. Elevated inflammatory parameters are found in the blood. The erythrocyte sedimentation rate is elevated, as are the CRP level and the leukocyte count. The blood anti-streptolysin titer is also elevated. The elevated ASL titer reflects a passed streptococcal infection. Positron emission tomogram shows increased sugar metabolism in the striatum in the brain. In addition to minor chorea, other symptoms of rheumatic fever are usually found. The so-called major criteria according to Jones-Standard include cardiac inflammation, acute inflammation of the joints, rheumatic erythema, or rheumatic nodules under the skin.
Complications
In most cases, chorea minor results in movement disorders. Mainly uncontrollable and also uncoordinated movements occur. These can spread to the legs, feet, and arms. For outsiders, these movements seem bizarre and incomprehensible, so that social problems can arise. Often the patient himself does not notice these movements. Children are also affected by these movements and can become victims of bullying and teasing. In children, chorea minor has a particularly negative effect on writing. The use of ordinary objects such as knives and forks is also difficult, and the affected person often appears clumsy. This limits the patient’s everyday life. Aspiration is also possible, which in the worst case can be fatal. Especially in stressful situations, hyperkineses and disturbances of concentration occur. Treatment is by administration of penicillin and is successful in most cases. However, penicillin must continue to be taken after treatment to prevent the development of sequelae. In case of psychological complaints, visits to a psychologist or appropriate medication are possible, which likewise do not lead to further complications.
When should one go to the doctor?
If the symptoms of chorea minor or chorea Sydenham occur, it is a neurological autoimmune disease that requires treatment. The secondary disease, triggered by streptococci, usually develops after a rheumatic fever or tonsillitis. The resulting movement disorders are similar to those of Huntington’s disease. In contrast to this hereditary disease, however, the movement disorders or hyperkineses in chorea minor are acute rather than lifelong. Most of those affected by chorea rheumatica or chorea infectiosa are children under the age of 15. Therefore, a visit to the doctor is absolutely necessary. This is because chorea minor leads to inflammation in the brain and damage to the so-called basal ganglia. Swallowing disorders can lead to inhalation of drinks and food components into the lungs. This can be fatal. Often, the symptoms of chorea minor are not correctly attributed. Affected children often compensate or suppress them. When suspecting that something might be wrong after a rheumatic fever or tonsillitis, a doctor should be consulted. He or she will do everything possible to check the blood for inflammatory parameters and an elevated leukocyte count. A positron emission tomogram can check for sugar metabolism in the brain. A search for major criteria such as acute inflammation of the joints, cardiac inflammation, rheumatic erythema, or rheumatoid skin nodules is necessary. Treatment with penicillin is effective.
Treatment and therapy
Therapy is similar to the treatment of rheumatic fever. Patients receive high doses of penicillin for ten days. This is to eliminate residual streptococci. Cortisone is administered to reduce inflammation. For six to twelve weeks, patients also take salicylates. If necessary, psychological symptoms can be treated with sedatives. In rare cases, neuroleptics are used.
Outlook and prognosis
Minor chorea has a good prognostic outlook. In most patients, the course of the disease is reversible. Nevertheless, in rare cases, lifelong impairment or sequelae result from the disease.With adequate medical care, most patients diagnosed with chorea minor can be completely cured. Within the therapy, the functionality of the basal ganglia can be fully restored, as they are not permanently damaged in chorea minor. They are subject to temporary impairment because it is a curable inflammation. If the cause is treated, patients have the prospect of a life without sequelae or residual impairment. Over 90% of sufferers show recovery after approximately 2-3 months of medical treatment. Within an average of 4-5 months from the start of treatment, all symptoms gradually regress completely until there is complete freedom from symptoms. The time of healing depends on the severity. It takes longer the more cells of the basal ganglia have been affected and the greater the inflammation in the brain. 10% of patients suffer residuals in the further course despite the good healing outlook. This results in sequelae such as inner restlessness, psychomotor problems or a new relapse. The relapses occur despite the use of prophylactic examinations and treatments offered.
Prevention
After a patient has persevered through the disease, they receive benzathine penicillin monthly for a period of five years. Without this prophylaxis, severe recurrences occur in half of all cases. To prevent further infection, chronic sources of streptococcal infection, such as enlarged tonsils or decayed teeth, should be eliminated.
Follow-up
In chorea minor, there are usually few or even no follow-up measures and options available to the affected person. In any case, early detection of the disease must take place to prevent further complications or discomfort. The earlier a doctor is contacted in the case of chorea minor, the better the further course of this disease usually is. The affected person should therefore see a doctor at the first symptoms or signs. Chorea Minor is usually treated by taking medication. As antibiotics are mainly taken, these should not be taken together with alcohol. The patient should also pay attention to a regular intake with a correct dosage in order to completely alleviate the symptoms. Furthermore, a doctor should always be consulted first if there are any questions or if anything is unclear. Since chorea minor can also lead to psychological complaints, medication can also be taken to alleviate these complaints. However, conversations with one’s own family or friends are also very helpful. Chorea Minor does not usually have a negative effect on the life expectancy of the affected person, if it is treated in time and correctly.
What you can do yourself
In everyday life, the affected person can take care to maintain a stable immune system through his lifestyle. With a balanced diet, food containing vitamins and regular exercise, he can strengthen his organism and maintain his health. If sufficient minerals and trace elements are taken in through the diet, the organism can quickly mobilize defenses against invading germs. This reduces the risk of illness and at the same time shortens the healing period in the event of an illness. Fluid intake must be monitored and should be about two liters a day for an adult. In times of increased risk of infection, regular hand washing can prevent infection. In cold temperatures, the neck and head should be adequately covered. If dental problems exist, they should be treated by a doctor as soon as possible. As a preventive measure, professional dental cleanings can be performed regularly and teeth should be brushed after meals. This reduces the risk of tooth decay. In parallel, the consumption of harmful or toxic substances should be avoided. Consumption of alcohol or nicotine weakens the organism and makes it vulnerable. For sufficient regeneration after stress or physical exertion, regular breaks and rest periods should be taken. In addition, the sleeping conditions should be adapted to the optimal needs.
