Human herpesvirus 7-associated encephalitis diagnosed by metagenomic next-generation sequencing in pediatric patients: a retrospective study

Background The objective of this study was to describe the clinical features, treatment and prognosis of immunocompetent children with human herpes virus 7 (HHV-7)-associated encephalitis. Methods Sixteen children with HHV-7-associated encephalitis were diagnosed by metagenomic next-generation sequencing of their cerebrospinal fluid and followed up for 3 months. Results The median age of the cohort was 8.6 years (range, 1.4–11.8) and comprised of 8 males and 8 females. The most common presenting symptoms were fever (12/16, 75.0%), headache (10/16, 62.5%), and vomiting (8/16, 50.0%). Abnormal electroencephalography and encephalitis-related neuroimaging findings were obtained in 50.0% (6/12) and 25.0% (4/16) of the patients, respectively. 68.8% of the patients were treated with either acyclovir or ganciclovir. Unfavorable outcomes occurred in three patients, including the death of a 2-year-old child. Conclusion Pediatric HHV-7-associated encephalitis generally has a favorable prognosis, but severe cases do occur. Early recognition is important for increasing clinicians’ awareness of this condition.