Background/Objectives: Satoyoshi syndrome is a rare, autoimmune disorder currently diagnosed based on clinical criteria: painful muscle spasms, diarrhea, and alopecia. Two previous reports showed a specific immunoreactive band in three Satoyoshi syndrome patients using Western blot analysis, with brain homogenate as the antigen source. These findings could be the basis for a future diagnostic test. The aim of our study was to evaluate the efficacy of using SH-SY5Y cell lysate instead of brain homogenate for a potential laboratory test for Satoyoshi syndrome using the Western blot technique. Methods: Western blot analyses were conducted using brain homogenate, SH-SY5Y cell lysates, and differentiated SH-SY5Y cell lysates. Serum samples were obtained from three Satoyoshi syndrome patients, alongside control samples from thirty blood donors and six patients with other neurological conditions. Results: Sera from patients with Satoyoshi syndrome displayed a three-band pattern in the 70-100 kDa range. This pattern was reproducible across all tested antigen sources (brain homogenate, SH-SY5Y lysate, and differentiated SH-SY5Y lysate) but was not observed for the sera from the control groups. The bands were more visible when using either type of SH-SY5Y lysate compared to brain homogenate. No differences were found between the SH-SY5Y lysate and the differentiated SH-SY5Y lysate. Conclusions: Sera from our Satoyoshi syndrome patients showed a specific band pattern that could be used for a future evaluation of Satoyoshi syndrome using Western blot. The use of SH-SY5Y cell lysate vs. brain homogenate as an antigen source may improve visualization and reproducibility of the immunobands and be less costly.

Satoyoshi syndrome (also known as Komuragaeri disease ) is a rare disorder of unknown etiology, with progressive muscle spasms, whole-body hair loss, and diarrhea as its main symptoms, particularly progressive skeletal muscle spasms and pain. Because of the lack of a clear etiology and pathogenesis of Satoyoshi syndrome, Western medicine lacks established effective therapies, and the long-term prognosis of the treatment of this disease is poor, unable to improve multiple symptoms simultaneously and prevent the recurrence of the disease. In recent years, acupuncture has been increasingly explored as a complementary treatment for autoimmune diseases. It is believed to exert its effects by modulating the neuroendocrine-immune network, enhancing immune cell function, and restoring homeostatic pathways. These mechanisms enable acupuncture to provide immune modulation, ultimately achieving a holistic and bidirectional regulatory effect. We report the case of a 54-year-old male police officer who had Satoyoshi syndrome for more than five years. After six months of acupuncture treatment, the patient's chronic diarrhea completely disappeared, and the occasional painful muscle cramps and insomnia significantly improved. After six months of follow-up, the patient's condition was stable. In this study, we believe that acupuncture therapy is of great significance for the improvement of diarrhea, immediate and long-term analgesia, and stabilization of the Satoyoshi syndrome.

Satoyoshi syndrome is a rare systemic autoimmune disease that presents with painful muscle spasms. We report a case of impending central retinal vein occlusion (CRVO) secondary to granulomatous pan-uveitis in a 32-year-old woman with Satoyoshi syndrome. At the age of 7 years, she developed generalized hair loss and painful spasms and was diagnosed with Satoyoshi syndrome. Her current symptoms included sudden metamorphopsia and decreased visual acuity in the left eye. She visited our hospital with extensive intraretinal hemorrhage (including the macula), meandering of the retinal veins, and swelling of the optic disc. Fluorescence fundus angiography demonstrated hyper fluorescence of the optic disc and leakage from the retinal veins, suggesting CRVO associated with optic papillitis and segmental periphlebitis. In the left eye, there were 2 + cells in the anterior chamber and 1 + in the anterior vitreous. We increased the existing dose of prednisolone for the treatment of uveitis and started her on oral aspirin and kallidinogenase for CRVO. The impending CRVO gradually subsided, and her visual acuity improved. However, during the subsequent treatment course, angle nodules were observed in the left eye, and the intraocular pressure (IOP) gradually increased. Although the angled nodules disappeared with topical corticosteroid treatment, the IOP did not reduce and became uncontrolled. Therefore, we performed trabeculotomy first, followed by trabeculectomy, after which the IOP decreased to approximately 10 mm Hg. Unilateral granulomatous pan-uveitis and impending CRVO were observed in this patient. Several cases of Satoyoshi syndrome complicated by various autoimmune or immunological disorders have been reported. However, to the best of our knowledge, no reports of Satoyoshi syndrome presenting with uveitis or CRVO have been published. Physicians should consider uveitis as a complication of Satoyoshi syndrome.

Satoyoshi syndrome is a rare multisystem disease of presumed autoimmune aetiology. We carried out a systematic review to evaluate the available evidence to support that autoimmune hypothesis. We searched for Satoyoshi syndrome cases in PubMed, the Web of Science and Scopus up to January 2022, using keywords 'Satoyoshi syndrome' or 'Komuragaeri disease'. Data on symptoms, associated autoimmune diseases, presence of autoantibodies and response to treatment were collected. A total of 77 patients from 57 articles published between 1967 and 2021 were included; 59 patients were women. The mean age at diagnosis was 21.2 years. All cases had painful muscular spasms and alopecia. Frequent manifestations included: diarrhoea, malabsorption, growth retardation, amenorrhoea and bone deformity. Satoyoshi syndrome was associated with other autoimmune diseases: myasthenia gravis, autoimmune thyroiditis, idiopathic thrombocytopenic purpura, atopic dermatitis, bronchial and lupus erythematosus. Autoantibody determinations were performed in 39 patients, of which 27 had positive results. The most frequently detected autoantibodies were ANAs. Other less frequently found autoantibodies were: anti-acetylcholine receptor antibodies, anti-DNA antibodies, antithyroid antibodies, anti-glutamic acid decarboxylase (anti-GAD) and anti-gliadin antibodies. Pharmacological treatment was reported in 50 patients. Most of them improved with CS, immunosuppressants and immunoglobulins, or a combination of these medications. Satoyoshi syndrome is associated with other autoimmune diseases and a variety of autoantibodies. Improvement after CS or other immunosuppressant treatment was observed in 90% of cases. These data support an autoimmune aetiology for Satoyoshi syndrome. More studies including systematic determination of autoantibodies in all patients with Satoyoshi syndrome will help us advance in our understanding of this disease.

探讨一例成人起病的Satoyoshi综合征合并意义未明的单克隆丙种球蛋白病（MGUS）的临床、电生理及病理学特点。Satoyoshi是以痛性肌肉痉挛、脱发、腹泻为临床特点，又称进行性痛性肌痉挛-脱发-腹泻综合征。临床报道的病例数较罕见，且多为青少年发病。本例患者为成年起病，临床表现为发作性痛性痉挛、脱发及腹泻，并实验室检查发现有MGUS。通过总结该病例的临床特点，加深对该病的认识。.