What neurological symptom is characteristic of Syndenham chorea?

Syndenham chorea, also known as chorea minor, is characterized by involuntary irregular movements that are often sudden, non-repetitive, and occur in a dance-like manner. These movements can affect various parts of the body and are typically non-contextual, meaning they happen without any intention from the person. This symptom arises as a result of an autoimmune reaction that typically follows a streptococcal infection, such as rheumatic fever.

Involuntary movements in Syndenham chorea can include twitching, jerking motions, and can also affect the face, arms, and legs. Patients may unexpectedly drop objects or may have difficulties with fine motor tasks. The nature of these movements is distinctive and helps differentiate this condition from other neurological disorders that may present differently, such as seizures or dystonias.

Therefore, the hallmark of Syndenham chorea is the presence of these irregular, involuntary movements, making it the characteristic symptom of this disorder.