Anti⁃neurofilament heavy chain antibody⁃associated encephalitis: one case report and literature review

Abstract

Objective To report and analyze the clinical features of the first documented case in China of anti⁃neurofilament heavy chain (NfH) antibody⁃associated encephalitis. Methods and Results A 63⁃year⁃old female presented with cognitive impairment, recurrent epileptic episodes, and aphasia. Head MRI showed multiple abnormal signals in bilateral frontal and parietal lobes, and slight swelling in some gyri, dilatation of the supratentorial ventricular system and brain atrophy, especially in bilateral temporal lobes and hippocampus. 18F⁃DPA714 PET/MRI showed abnormal uptake in multiple brain regions in the frontal, temporal, parietal and occipital lobes, suggesting neuroinflammation in the brain. EEG showed frequent epileptiform discharges. Cerebrospinal fluid white cell count and glucose were elevated. Serum and cerebrospinal fluid antibodies related to autoimmune encephalitis were negative. Serum tissue⁃based indirect immunofluorescence assay showed cerebellar neurofilament⁃like fluorescence surrounding Purkinje cells, further detection of neurofilament protein⁃related antibodies, it suggested high titer of serum NfH⁃IgG (1∶1000). The patient was diagnosed with anti⁃NfH antibody⁃associated encephalitis. After treatment with intravenous immunoglobulin and methylprednisolone, the prognosis was improved. Conclusions Anti⁃NfH antibody ⁃ associated encephalitis is a rare and clinically complex condition. The myriad of symptoms complicates early diagnosis and differential identification. Early initiation of immunomodulatory therapy may offer prognostic advantages.

DOI: 10.3969/j.issn.1672⁃6731.2024.05.009