Objective: To describe the clinical features and presentation of an auto-immune cerebellar ataxia with asymmetric Holmes tremor and its therapeutic response.

Background: Autoimmune cerebellar ataxia (1) (2)present with insidious onset progressive pan-cerebellar syndrome, with well-defined antibodies, viz, paraneoplastic or autoimmune. Absence of the these defined antibodies describe primary autoimmune cerebellar ataxia.

Method: Describe a case of autoimmune cerebellar ataxia with rubral tremor, with normal imaging and its possible association with anti ribosomal P antibody and exquisite response to immunotherapy.

Results: This 69 year old lady presented with subacute onset progressive pan-cerebellar syndrome with asymmetric rubral tremor of right upper and lower limb since march 2021.By January 2022, she was wheel chair bound with SARA score of 21/40.Her examination shows pan cerebellar syndrome with 2-3 Hz asymmetric postural and rest tremor of right upper and lower limb. Her MRI brain was unremarkable. CSF was acellular with normal protein and sugar with normal IGG index and undetectable OCB. Her C-ANCA,P-ANCA,CSF TPHA were negative. Antinuclear Antibody profile showed strong positivity for Anti ribosmal P antibody.Etiological evaluation including connective tissue markers,Paraneoplastic antibody profile in serum and CSF (amphyphysin/cv2/Ma/TA/Yo/Ri/SOX1/Titin/Hu),anti Tissue transglutaminase,Anti GAD antibody and HIV serology was negative. whole body FDG PET CT was negative for abnormal uptake except, in left inferior olivary Nucleus.She was initially treated with IV Steroid pulse with IVIG ( 2gm/kg) and subsequently with two doses of Rituximab infusion ( 1gm each) in June 2022. She improved symptomatically. On last follow up in January 2023, her SARA score was 4/40 and tremor has resolved.

Conclusion: Autoimmune cerebellar ataxia is a clinical diagnosis which needs a high index of suspicion for primary diagnosis. Owing to the treatability and need for early initiation to take advantage of the cerebellar reserve, prompt identification is essential. Anti-Ribosomal P antibody has been previously described in proven SLE (3)patients, with cerebellar ataxia. The exquisite response to therapy in our case could suggest an autoimmune mechanism with Anti-Ribosomal P antibody as a marker

References: 1. Hadjivassiliou M, Graus F, Honnorat J, Jarius S, Titulaer M, Manto M, et al. Diagnostic Criteria for Primary Autoimmune Cerebellar Ataxia-Guidelines from an International Task Force on Immune-Mediated Cerebellar Ataxias. Cerebellum. 2020 Aug;19(4):605–10.
2. Mitoma H, Manto M, Hadjivassiliou M. Immune-Mediated Cerebellar Ataxias: Clinical Diagnosis and Treatment Based on Immunological and Physiological Mechanisms. JMD. 2021 Jan 31;14(1):10–28.
3. Iwasaki Y, Okamoto A, Shoda H, Takahashi Y, Fujio K, Kawahata K, et al. Subacute cerebellar ataxia and atrophy developed in a young woman with systemic lupus erythematosus whose cerebrospinal fluid was positive for antineuronal cell antibody. Lupus. 2012 Mar;21(3):324–8.

« Back to 2023 International Congress

MDS Abstracts - https://www.mdsabstracts.org/abstract/the-role-of-anti-ribosomal-p-antibody-in-autoimmune-cerebellar-ataxia/