A paraneoplastic cerebellar degeneration syndrome with positive anti-amphiphysin and anti-titin antibodies

Paraneoplastic neurologic syndromes are rare disorders in which an abnormal immune response to a tumor cell is observed. The most common subtype is paraneoplastic cerebellar degeneration, presenting with clinical findings such as tremor, dysarthria, and ataxia and frequent anti-Yo antibody positivity. Anti-amphyphisin antibodies have been defined in Stiff Person syndrome, and in recent years upon its detection in malignancies, limbic encephalitis, and clinical findings such as cerebellar dysfunction, a new definition has been brought as non-stiff anti-amphyphisin syndrome (NSAS). In this case report, we presented a 75-year-old female patient diagnosed with NSAS due to clinical symptoms such as tremor and dysarthria, cerebellar atrophy detected on computed tomography, and anti-titin and anti-amphyphisin antibody positivity.