[Clinical and genetic analysis of a patient with Neuronal intranuclear inclusion body disease characterized by cortical enhancement in the posterior brain region].

Objective: To explore the clinical, imaging, and genetic characteristics of an adult patient with sporadic Neuronal intranuclear inclusion disease (NIID).

Methods: A patient who had visited the First People's Hospital of Chenzhou on August 6, 2023 was selected as the study subject. Results of clinical examination, neuroimaging, and genetic testing were retrospectively analyzed along with a literature review. The number of GGC trinucleotide repeats in the 5'-untranslated region of the NOTCH2NLC gene was determined by GC-PCR.

Results: The patient had presented with episodic encephalopathy, with enhanced magnetic resonance imaging showing enhancement features of the posterior cerebral cortex during the period of acute episode. Genetic testing revealed an increased number of GGC repeats (n = 97) in the 5'- untranslated region of the NOTCH2NLC gene, which confirmed the diagnosis of NIID.

Conclusion: Clinical attention should be paid to the enhanced MRI findings of patients with adult-onset NIID, for whom posterior cortical enhancement may be characteristic manifestation during the acute phase of encephalopathy-like episode.