Satoyoshi syndrome is a rare multisystem disorder characterized by progressive intermittent painful spasms, hair loss, and diarrhea, often accompanied by endocrine abnormalities, skeletal anomalies, and gastrointestinal inflammation. Its etiology is presumed to involve autoimmune mechanisms. This paper reports a case of Satoyoshi syndrome primarily presenting with neurological symptoms.

The patient, a 30-year-old female, presented with a chief complaint of progressive involuntary body movements for over 4 years upon admission. Initially, she experienced episodic involuntary tremors in her limbs, progressing to tremors accompanied by painful spasms. These episodes, exacerbated by insomnia, became nearly continuous and were partially relieved by diazepam. Head MRI, EEG, and electromyography showed no abnormalities. Additional history revealed that ten years prior, she experienced generalized hair loss within one year, concurrent with amenorrhea. Regular menstrual cycles restored with hormone replacement therapy, followed by sparse and reduced menstruation upon discontinuation. Physical examination revealed various forms of increased movements but no other significant abnormalities. During hospitalization, she developed diarrhea, revealing a history of chronic diarrhea. Stool analysis indicated significant fat droplets, which is not observed upon admission. In the patient's antinuclear antibody profile and the antiphospholipid antibody profile, there were positive results.

The patient should be suspected of having Satoyoshi Syndrome. She was treated with carbamazepine and corticosteroid pulses followed by sequential oral corticosteroid, leading to symptom improvement. Immune therapy with methotrexate and hydroxychloroquine, in addition to aspirin and facial botulinum toxin injections, further ameliorated spasms and involuntary movements. The patient's symptoms remained stable during follow-up.

Numerous neurological symptoms might manifest as one of the multisystem presentations of rare diseases. Neurologists should maintain a comprehensive perspective and not overlook non-neurological symptoms in patients. Distinguishing involuntary movements can be particularly challenging for neurologists. Despite advances in auxiliary examinations, accurate symptom assessment remains a prerequisite for definitive diagnosis.