biostudies-literatureMerati MNINDS NIH HHS278-281https://www.ebi.ac.uk/biostudies/studies/S-EPMC9620397biostudies-literatureUnknown42(2)<h4>Abstract</h4>A 62-year-old man presented with headache, fever, and malaise. He was diagnosed with Anaplasma phagocytophilum, confirmed by serum polymerase chain reaction, and started on oral doxycycline. After 5 days of treatment, the patient began to experience gait imbalance with frequent falls, as well as myoclonus, and confusion. Examination was notable for opsoclonus-myoclonus-ataxia (OMA) and hypometric saccades. Cerebrospinal fluid (CSF) autoimmune encephalitis panel demonstrated a markedly elevated neuronal intermediate filament (NIF) immunoglobulin G antibody titer of 1:16, with positive neurofilament light- and heavy-chain antibodies. These antibodies were suspected to have been triggered by the Anaplasma infection. Repeat CSF examination 8 days later still showed a positive Journal of neuro-ophthalmology : the official journal of the North American Neuro-Ophthalmology SocietyA Case of Opsoclonus-Myoclonus-Ataxia With Neuronal Intermediate Filament IgG Detected in Cerebrospinal Fluid.PMC9620397R01 NS126227Balcer LJMcKeon AFrucht SJHu JRucker JCGaletta SLMerati MfalseA Case of Opsoclonus-Myoclonus-Ataxia With Neuronal Intermediate Filament IgG Detected in Cerebrospinal Fluid.<h4>Abstract</h4>A 62-year-old man presented with headache, fever, and malaise. He was diagnosed with Anaplasma phagocytophilum, confirmed by serum polymerase chain reaction, and started on oral doxycycline. After 5 days of treatment, the patient began to experience gait imbalance with frequent falls, as well as myoclonus, and confusion. Examination was notable for opsoclonus-myoclonus-ataxia (OMA) and hypometric saccades. Cerebrospinal fluid (CSF) autoimmune encephalitis panel demonstrated a markedly elevated neuronal intermediate filament (NIF) immunoglobulin G antibody titer of 1:16, with positive neurofilament light- and heavy-chain antibodies. These antibodies were suspected to have been triggered by the Anaplasma infection. Repeat CSF examination 8 days later still showed a positive 2022-01-01T00:00:00Z2022 Jun2025-04-27T02:14:54.447Z2025-04-06T18:33:19.941ZS-EPMC96203973559415710.1097/wno.000000000000159910.1097/WNO.0000000000001599