Which are the causes of Sydenham Chorea?

Sydenham Chorea, also known as St. Vitus' Dance, is a neurological disorder characterized by involuntary movements and muscle weakness. It is primarily caused by an autoimmune reaction triggered by a group A streptococcal infection, specifically the bacteria Streptococcus pyogenes. This condition is most commonly seen in children and adolescents, particularly between the ages of 5 and 15.

Autoimmune Reaction: The main cause of Sydenham Chorea is an autoimmune reaction that occurs as a result of a previous streptococcal infection. When the body is infected with Streptococcus pyogenes, the immune system produces antibodies to fight off the infection. However, in some individuals, these antibodies mistakenly attack certain parts of the brain, leading to the development of Sydenham Chorea.

Streptococcal Infection: Sydenham Chorea is often preceded by a streptococcal infection, such as strep throat or scarlet fever. The bacteria responsible for these infections release toxins that can trigger an immune response in susceptible individuals. It is believed that the antibodies produced during the infection cross-react with certain brain cells, leading to the characteristic movement abnormalities seen in Sydenham Chorea.

Genetic Predisposition: While the exact genetic factors contributing to Sydenham Chorea are not fully understood, there is evidence to suggest a genetic predisposition to the condition. Some individuals may have a genetic susceptibility that makes them more prone to developing an autoimmune reaction following a streptococcal infection. However, more research is needed to determine the specific genes involved in this process.

Other Factors: In addition to the autoimmune reaction triggered by streptococcal infection, other factors may contribute to the development of Sydenham Chorea. These include hormonal changes during puberty, as the condition is more commonly seen in children and adolescents. Additionally, certain environmental factors and stressors may play a role in triggering or exacerbating the symptoms of Sydenham Chorea.

In conclusion, Sydenham Chorea is primarily caused by an autoimmune reaction triggered by a previous streptococcal infection. The antibodies produced during the infection mistakenly attack certain parts of the brain, leading to the characteristic involuntary movements and muscle weakness seen in this condition. While genetic predisposition and other factors may also contribute, further research is needed to fully understand the underlying causes of Sydenham Chorea.