Neurosyphilis presenting as status epilepticus and hemiplegia diagnosed by metagenomic next-generation sequencing: A case report

The current study aimed to present a diagnostically challenging case of neurosyphilis manifesting with atypical neurological symptoms, emphasizing the importance of clinical vigilance and advanced diagnostics in avoiding misdiagnosis and inappropriate intervention. In the present study, a case of neurosyphilis, initially misdiagnosed and treated as acute cerebral infarction, is reported. Diagnostic analyses included serial brain magnetic resonance imaging (MRI), continuous electroencephalography (EEG) monitoring and metagenomic next‑generation sequencing (mNGS) of cerebrospinal fluid (CSF) for pathogen identification. The results revealed that the patient presented with status epilepticus and hemiplegia. Follow‑up MRI after transfer revealed extensive patchy cortical and subcortical white matter abnormalities in the right cerebral hemisphere. Notably, a thalamic signal abnormality observed on pre‑thrombolysis diffusion‑weighted imaging had notably diminished. EEG demonstrated periodic lateralized epileptiform discharges (PLEDs). CSF mNGS definitively identified 883 specific sequences of Treponema pallidum. Despite targeted anti‑syphilitic and antiepileptic therapy, the patient's consciousness failed to improve, with persistent PLEDs on EEG. The patient was later discharged against medical advice due to pulmonary infection and hypotension and was subsequently confirmed deceased. In conclusion, the current case illustrates the markedly diverse and misleading presentations of neurosyphilis, which can mimic other acute neurological conditions. It underscores the need for maintaining a high index of suspicion and utilizing comprehensive diagnostic tools, including mNGS, to ensure accurate diagnosis and prevent the consequences of missed diagnosis or incorrect treatment.