Abstract
BACKGROUND: Cytomegalovirus (CMV) infections in the population are mostly subclinical, inapparent, or latent. However, it is rare in brain tissue. Most reported CMV encephalitis cases were patients with immunodeficiency. The diagnosis and detection rate of CMV encephalitis in patients with normal immune function needs to be further improved. CASE SUMMARY: An 86-year-old male was admitted due to a sudden onset of unconsciousness for 3 h. The patient developed status epilepticus and was relieved after antiepileptic treatment. Encephalitis was considered due to the high signals of diffusion-weighted imaging sequences in the right central region by magnetic resonance imaging. Metagenomic next-generation sequencing (mNGS) of blood and cerebrospinal fluid revealed CMV, with unique reads number being 614 and 1, respectively. Simultaneous quantitative PCR results showed CMV positive in blood samples and negative in cerebrospinal fluid samples. The patient was finally diagnosed as CMV encephalitis with status epilepticus. After the antiviral, hormonal, and γ-globulin pulse therapy, the patient's condition improved, and he was finally discharged. CONCLUSION: mNGS could be a reliable approach for the diagnosis of CMV encephalitis, with high efficiency, sensitivity, and specificity.